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Shed Foundation Kit Guide

Should You Put a Manufactured Shed Foundation Kit Under Your Shed?

Long before you bolt the first two pieces of your new garden shed together, you need to decide what type of foundation it should be sitting on. Like any other structure, your needs a good strong foundation under it to perform at its best. When it comes to any type of building, the foundation's job is to support the walls just as their job is to support the roof. Nothing is more important to the life of your shed than a good foundation.

Getting Started

There are many reasons why you shouldn't just plop your shed on the ground. The lack of a foundation can lead to rot or rust, you will always be fighting the growth of weeds and grass in your shed, and in time you will find the doors no longer function properly. One option for putting a firm foundation under your shed is a foundation kit.

Some manufacturers offer foundation kits for their sheds and there are a number of companies that offer their own. These kits offer a firm foundation that can be used to support most standard sized sheds and come in various styles.

With some kits, you may need to purchase extra supplies. For example, the foundation kits offered by Arrow require you to buy multiple sheets of plywood to build the floor. Bear in mind you should never place your shed directly on the ground as this can lead to significant damage to the structure.

Should I Put a Substrate Down?

First, let's talk about what a substrate is. According to the dictionary, a substrate is a “substance or layer that underlies something.” Sounds a bit confusing, doesn't it? In this particular case, what we are talking about it putting something on the ground between it and your shed's foundation.  There are two different reasons for putting your shed's foundation on something besides plain dirt. First, a layer of gravel will give any water a way to drain into the soil. Secondly, using gravel will provide much better support for your shed's foundation and its accompanying shed along with everything you plan to put in it.

For this particular application, you should be able to use the larger size gravel as you want the spaces between each piece of gravel for drainage purposes.

Alternatively, you could use pavers spaced at intervals to provide the necessary support for your foundation. But, if you are going to do so, be sure you use enough to provide adequate support for your foundation and shed.

Foundation Kits Come in Different Styles

There are several different styles of shed foundation for you to choose from.

The Frame Foundation

Image courtesy of Haddi

This particular type of foundation is built as a framework with an outer frame along with inner stringers. The finished product may look a little like a studded wall laying on the ground or it may look like the game board from Celebrity Squares.  These foundations can be built from steel or wood and provide outstanding support for your shed.  Typically, they are bolted together for extra strength and durability, but some of the cheaper wood kits are nailed together (try to avoid these as they have a limited lifespan).

The Portable Base

Elegant-Storage-Shed-Base-Preparation-70-For-Your-Bike-Storage-Shed-Rubbermaid-with-Storage-Shed-Base-PreparationImage courtesy BlueCarrot.Com

Typically, these are made from timber pieces that can be assembled by two people in a short period of time. They are designed to be staked in place at all four corners using large spikes. Before installing this type of foundation, you should lay a sheet of plastic down and cover it with a layer of pea gravel for better drainage and keep weeds and grass from growing. The good thing about this type of shed foundation is that you can easily move it when the time comes.

The Ecobase Shed Foundation

nnj_web1_9b20ce70-1135-460e-a1d7-48e0a49bca01_largeImage courtesy nnjnettingsuppliesltd

This type of shed foundation uses a series of lightweight polyethylene grids that can be assembled to match the size of your shed and can be assembled in minutes. The grids are fully reusable, and can easily be cut to size as needed. These kits are relatively affordable and because they are lightweight can be shipped directly to your home. This material will not rot or rust a major problem with wood and metal foundations.

The Advantages of Using a Shed Foundation Kit

There are several advantages to using a shed foundation kit to support your shed, including:

No Worries About Your Soil Composition

concrete-slabImage courtesy Manisha

If you plan to use a concrete slab foundation, you have to worry about the composition of the soil where you plan to pour the slab. If your soil has a lot of clay in it, you have to worry about expansion and contraction over time. This will eventually cause your foundation to shift and crack.

No Worries About Tree Roots

foundation-problems-crack-concrete-slabImage courtesy of Today's Homeowner

If you have trees planted near the location you have in mind for your shed, they will eventually reach a point where they start to grow under your slab. In time, the roots will begin to lift your slab, causing it to crack and break. When you use a foundation kit, you don't have to worry about tree roots causing this type of damage.

No Worries About Drainage

IMG_20150913_152628Image courtesy of JeanandAaron 

Unless you take the time to build in proper drainage, you may end up with water coming up over the foundation and getting into your shed. In most cases, the average homeowner has no idea what the drainage is like where they plan to put their shed. Drainage is never a problem with a shed foundation kit.

Less Expensive

Unless you can pour your own slab, the average shed foundation kit will cost significantly less than having a cement company come to your house to pour your shed foundation. Even if you can pour your own cement, buy the time you pay for all the necessary tools, the framing, the cement, and the cement mixer, you will have spent far more money than the cost of the average foundation kit.

Do All Shed Manufacturers Offer Shed Foundation Kits?

Not all shed manufacturers offer purpose-built foundation kits for their sheds. Many believe the built-in floors they supply are all that is needed. Here is a look at the more popular brands and whether or not they offer foundation kits.

Brand Foundation Kit
Arrow Yes
Lifetime No
Duramax Yes
Best Barn No
Little Cottage Company No

This is only a small sample of the many shed manufacturers on the market, but they are also among the best-selling brands available. As you can see only a couple of the companies offer matching foundations. Many believe that the floor of their sheds is strong enough. But the reality is that even these sheds need to be supported by some form of foundation. But those that do offer foundation kits, offer kits that are perfectly matched and designed for their sheds, thus providing the best possible support.

Installing Your Shed Foundation Kit

There are several steps involved in the installation of your shed foundation kit.

Clear and Level the Ground

This may be the most important part of setting the foundation for your shed. Using the method described above, make sure the ground you plan to put your shed on is perfectly level. Not being level can lead to water intrusion, but it can also put undue stresses on certain areas of your shed, leading to early failure.

Prepare the Soil

Once you have leveled the loose soil, you have a couple of choices. You can tamp the soil down to create a firm base and place the foundation directly on the ground, but this is not necessarily your best option as the soil will eventually erode causing your shed to lean. A better plan would be to level the soil, place a layer of landscaping fabric on top of it, and then cover the fabric with a layer of pea gravel. This will provide a much firmer base for your shed foundation kit to sit on, plus you have improved drainage, and won't have to worry about erosion.

Build and Secure the Foundation Kit

Assemble your shed foundation kit according to the manufacturer's instructions and lay it in place on your prepared soil. Even if the manufacturer doesn't suggest securing the foundation in place, you should consider doing so. Use several large spikes hammered deep into the ground to secure the foundation firmly in place. By securing your shed's foundation to the ground, your shed is more likely to be able to withstand any high winds the area you live in happen to experience.

Complete the Installation

The last part of the installation is to add any flooring materials the manufacturers suggest. For example, Arrow foundations require the addition of sheets of 3/4-inch pressure treated plywood for flooring, before you put your shed on top of it. Once everything is in place, be sure to recheck the entire foundation for level before you install the shed.

As long as you have not installed the shed, you can always make any necessary adjustments. Once you have the weight of the shed to deal with, making any adjustments could be next to impossible.

Take Your Time

One last thought, be sure to take your time preparing the ground you plan to install your shed on. The success or failure of any building is only as good as the foundation it is built on. Make sure the shed foundation kit you choose is the right size for your shed and is strong enough to support the weight of your shed and everything you plan to put in it.

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Paver Shed Foundation

How to Lay a Paver Shed Foundation

If you are planning to build or add a garden shed to your backyard, the most important step is to build a firm foundation for it to sit on.

A good paver shed foundation is the perfect base for your shed and not as hard to build as you might think.

First the Good News

Since building a paver shed foundation involves a certain amount of hard labor, it is always good to know just how much work you are going to be involved in.

The good news is that unless you are building a massive shed that is more like a barn than a shed, you should be able to complete this project in a weekend, leaving you with a little time at the end of each day for an ice-cold beer or two. On top of this, once your foundation is complete, it will be immediately ready for use, unlike concrete that needs time to cure before it can be used.

Before You Get Started

shed_pavement_land_preparationimage courtesy of ShedKing.Net

Before you start building your garden shed or laying the paver shed foundation, you need to take a good look at the ground in the area you plan to install your new shed.  There are a few things to be taken into consideration before you choose your final location.


If at all possible choose an area that is already reasonably level. Not only will this make building a level paver shed foundation much easier, it will take fewer materials and less time to build.


You should never build any type of foundation on ground that does not drain well. Ground that is continuously wet or subjected to flowing water is only likely to erode potentially causing significant problems further down the line.

Too Hard to Dig

No matter how you plan to install the pavers, try to avoid ground that is simply too hard to dig in or has a lot of rocks just below the surface. All you will be doing is creating more work for yourself or putting yourself in an almost impossible position.

Soil That is Too Soft

It should go without saying that you should not pick an area of your yard or garden where the ground constantly remains wet and soft. At least if you don't want to see your paver shed foundation and shed to tilt into the ground.

Paving Slabs – Choosing the Right Ones

council-paving-slabs-2Image courtesy of Watling Reclamation

The next good thing on our list is that pavers are very simple to find and come in an incredible array of sizes, shapes, and colors. You can go for the basic square concrete colored paver or step up to colors and patterns that extend beyond the walls of your shed to create a patio.

For the most part I prefer to use pavers that are 2 inches thick and 12 inches square. They are more than strong enough to support the shed when you build a proper paver shed foundation. At the same time, they are light enough for you to handle without too much strain. These should be readily available at your nearest discount hardware superstore or local garden store.

What Tools and Supplies Do You Need?

While you could simply lay the pavers on flat ground and call it a foundation, this is really not the best idea. But if you are going to build a paver shed foundation that will not only support the weight of your shed, but also last a lifetime, you will need a few tools and supplies to get the job done.  These include:

  • One or more bags of cement
  • One of more bags of builder's cement
  • A sufficient amount of gravel
  • Several pegs and a roll of string
  • A rubber mallet
  • A spirit level and a long 2×4
  • Sufficient pavers to cover the entire area
  • Stout leather gloves
  • Plastic or metal garden border
  • Vibrating compactor (from the nearest rental store)

Getting Started

Since your new paver shed foundation must be built strong enough to last for many years, every step of the building process has to be completed carefully and exactly, starting with marking out the space you plan to use.

To do this mark out each side of the space forming a square. The easiest way to make sure all four corners are square is to measure the distance between each pair of diagonally opposed corners. If they are the same, your corners are square. This method will work for both square and rectangular shaped foundations.

It's Time to Start Digging

Now that you have the area needed for your foundation marked out, it's time to get started with the fun part. So, grab your favorite work gloves and shovel and start digging. You need to dig the area to a depth of approximately six inches. This will give enough space for the gravel base, the sand and cement filler, and the pavers, leaving them at or just above ground level.

Once you have the soil dug out to the appropriate level, it needs to be compacted. Break out that rented vibrating compactor and go to town. Depending on the size of your foundation, this shouldn't take very long. However, it is a very important step as your foundation needs a firm base to stand upon.

Add the Gravel

The next step is to add a one-inch layer of gravel to the hole. Be sure to use either 21A or 21B gravel as it contains fillers to help fill in the air gaps between the pieces of gravel providing you with a much firmer base.

gravel-pavementImage courtesy of DIY Network

Once again you need to use the compactor to pack the gravel in place and create a smooth flat surface. Be sure to check your gravel layer using the 2×4 and spirit level to ensure it is perfectly level before proceeding to the next step.

Time for Sand

Mix together the sand and cement and then add a 2-inch layer of this mixture to the gravel. Smooth out the sand and then compact it to form a tightly compacted layer that is perfect level or as close as you can get to it. Making sure each layer is level is vital to the finished product. If one layer ends up being off kilter then every other layer you add on top of it will be off as well. The final result will be a shed that sits tilted and may end up being damaged.

sand_pavementImage courtesy of the DIY Network

It's Paver Time

Lay the pavers in the appropriate pattern covering the entire area and check each for level with the others. If you find any that are not level, you can use the rubber mallet to tap them down at each corner until they are level. Take your time with this step as any paver that happens to be out of level might crack or break once the shed is put in place, leaving a weak spot in your finished foundation.

Image courtesy of Paving Directorylaying a paver shed foundation

Add the Border

Whether you decided on the plastic or metal garden border, take it and install it around the outer edges of the pavers. It needs to be placed as close as possible to the pavers, any gap only leaves a place for weeds to grow. Anchor the border to the ground using the spikes provided with it or stakes you have purchased separately.
pavement_borderImage courtesy of Pinterest

Finishing Up

Spread a layer of the cement and sand mixture used in the foundation over the top of the pavers. Use a broom to spread the sand into the gaps, filling them in until they are flush with the pavers. Using your garden hose and a fine mist nozzle, lightly dampen the entire surface of your new paver shed foundation and walk away.

The water will cause the blend of sand and cement to solidify, permanently holding the pavers in place and creating an exceptionally strong foundation. It will also seal the gaps between the pavers, helping to keep water, ice, and snow from getting under the pavers and causing them to lift or crack. If you don't do this step, your foundation is likely to fail earlier than it should.

patio-pavers-1Image courtesy of SmashingPlates.US

Extra Information You Need to Know

  • If you have never created your own cement/sand mixture, it should be mixed in the ratio of one-part dry cement to eight parts dry sand.
  • Once the sand/cement mix has filled in the gaps, sweep the rest of it off the pavers. This way they won't turn into a hardened mixture that will affect the way your shed sits on the pavers.
  • The best way to lay pavers is to start in one corner and work your way out. Once you have the sand/cement level compacted in place, you should avoid walking on it as your footprints could affect the how level the pavers are when they are installed.
  • Don't be tempted to use large size gravels such as 56s or 57s as they do not contain the extra fillers found in 21A and 21B gravels. These fillers help hold the gravel in place by filling in the air gaps between each piece of gravel. Their absence will allow the gravel to shift as the soil erodes over the course of time.
  • Your finished foundation should be at least 12 to 18 inches larger on each side than the shed to help reduce the risk of ground erosion and to keep your shed nice and level.


There is a fair amount of work involved in laying a paver shed foundation. However, when you are done and sitting back looking at your new foundation, you will find all the hard work more than worth it. Of anything you can do when building your foundation, making sure each subsequent level is as level as you can possibly make it is the most important.

A tilted shed may have doors that don’t open and close properly, windows that won't work, and poor water drainage. Take your time with every step and you will have a paver shed foundation that might just outlast a shed or two.

If this has helped you with building your shed. Please let me know by contacting me hereYou can see more ZacsGarden on Facebook or Pinterest. Thanks for reading.

How to Build a Pier Shed Foundation

How to Build a Pier Shed Foundation

IS THE GROUND IN YOUR backyard uneven?


Does it tend to collect water right where you plan to build your shed?

If you answered yes to either of these questions, then building a pier foundation might be for you.

Since most sheds have a wooden floor, keeping it out of the water is an important part of making your shed last as long as possible. Building a shed in a place that you know is regularly damp may also void your warranty if you buy yourself a shed kit.

This article will help you with pier basics, including the different types of common pier foundations found, the tools and supplies you need as well as how to build a good shed foundation with piers.

First, check the Rules

Before you set out to build your pier foundation or add a shed to your backyard, the first thing you need to do is check the rules. Most localities have their own regulations regarding how your shed's foundation can be built, what type of materials can be used, and the size and location of your shed.

The good news is that if you are building a small shed then there is unlikely to be any requirements from the permit office (you can use a map to find your local permit office online, and see their requirements here). If you don’t take the time to figure out the rules before you get started, you may find yourself tearing it all down and starting over. At the same time, you might find yourself paying a relatively large fine for doing it wrong in the first place.

Two Types of Pier

There are two common types of piers use to build shed foundation, treated lumber posts, and concrete. The number of piers needed to properly support your shed is based on the overall size of the shed you plan to build.  The concrete piers with a pre-attached wood nailer must be buried into the ground, while the lumber ones must be placed in a hole and secured in place with cement.

pier shed foundation
The most common of these is the latter, typically made from pressure treated 4 x 4 lumber that is set in concrete creating a strong foundation for your shed. However, both styles can be used with equal success. The rest of it lies in how well you do the job of laying your foundation.

Tools You Will Need to Lay a Pier Shed Foundation

You need a number of tools to do this job right, including:

  • Rake – to help clear the ground and level it
  • Shovel – to help level the ground and dig the holes needed for the piers
  • Gloves – to keep your hands from being ruined
  • String – to mark the perimeter and pier locations
  • Tape Measure – to make sure you have the piers in the right locations
  • Level – to make sure the foundation of your shed is perfectly level
  • Large Hammer – to set the piers in place
  • Stakes – to mark the corners and pier locations

Supply List

  • Piers – either cement with wood nailers or pressure treated lumber (typically 4x4s)
  • Cement – if you are using wood piers
  • Screws – buy the ones made for use in pressure treated lumber as they are treated so they won't rust
  • Cordless screwdriver – make sure yours is powerful enough to drive the screws through the piers and into your foundation
  • Lumber – for your foundation
  • Gravel – to lay in the bottom of the pier holes in the ground.
  • Lengths of 2×4 – used to hold the piers upright until the cement has dried fully
  • Post Caps – to hold the foundation to the piers

Preparing the Ground

ground_preparation_for_pier_foundationImage courtesy of

The first step in laying a pier foundation is to prepare the ground where your shed is going to sit. Carefully scrape away any grass, roots, or debris to expose the soil. If the area does not drain properly consider digging down approximately 4 to 6 inches and filling the area with pea gravel. This will help to improve overall drainage.

Marking Out the Pier Locations

Start by marking out the perimeter of your shed, use stakes to mark the corners and run string between them.

Once you have marked out the corners, your next step is to mark the location of each pier needed to support your shed.  The recommended location of each pier is 4 feet on center. A simpler way to explain this is to create a grid matching the length and width of your shed. Then create a grid in which each square measures four feet by four feet. It should look like this:

mark_pier_locationsEach of these blocks measures exactly four feet by four feet

At each point where the lines of your grid intersect is where you will be placing the piers. Now that you know how many piers will be needed, you can buy the right number of premade concrete and wood piers or the correct amount of lumber and cement.

Now that you have a map of where you plan to lay the piers on paper, it's time to mark out the locations on the ground. There are a couple of ways you can do this. First, you can run strings along the ground to create the same grid pattern you have on paper and use the points at which they intersect to mark the spot (similar in many ways to “X” marks the spot.

Alternatively, you can measure each location carefully and use spray paint to mark the locations. However, this method may not be as accurate as the crossed string method above.

No matter which of these methods you choose, take your time. Accuracy is of the utmost importance at this point if you want your shed to be properly supported no matter what you plan to store in it.

Digging In

With all pier locations marked on the ground, it's time to dig in, literally. Grab your favorite leather work gloves and your favorite shovel, you have a lot of digging to do.  Each hole should be 12 inches in diameter and should be dug down at least 12 inches below the frost line in your area. If you are not sure where this line is, you can ask your local city regulatory board, they should have the information for you.

pier_foundation_diginImage courtesy of Deck Piers Depth

Make the holes round instead of square as cylindrical shapes offer far more support than square ones. If you look at many of today's bridges, they feature round piers for support. This follows along the same basic concept.

Pour 4 to 6 inches of gravel into the bottom of each hole and tamp it down. This will create a firm foundation for the wood or concrete piers.

If you are using pre-made concrete and wood piers, you can simply set them in the hole and fill in the holes around them. Once the foundation is attached, they are not going to move.

If you plan to use wood piers, place each pier in a hole, pour cement that has been mixed according to the instructions into the hole so that the hole is filled almost to the top.

At this point, you need to attach a pair of 2x4s to the pier and use your level to ensure the pier remains perfectly upright while the cement sets up. This is perhaps the most important step of the entire process. Piers that are not perfectly set can have a major negative impact on how level and well-supported your shed will be.

If you are using pre-made piers, you need to check for level as you are adding the soil back into the hole. You may even want to use smaller rocks and gravel to help add more support and stability for the piers.

Getting Ready for the Foundation

Before you move on to the next phase, adding the foundation, you need to give the cement plenty of time to set. It takes an average of 24 hours for the properly mixed cement to become hard enough to walk on. But it takes approximately 28 days for it to become fully cured and strong enough to hold your wood piers securely in place. If you try to work any faster, you run the risk of damaging the cement and in doing so reducing the risk of your foundation cracking.

pier_foundation_cementImage courtesy of Chezerbey

After letting the cement cure for the required 28 days, it's time to move onto the next phase. Getting everything ready for your new shed.

Now is the time to decide how far off the ground you want the foundation of your shed to sit. Starting with the shortest post, cut it off to match this height.  If possible start at one corner and then move to the opposite corner and do the same.

Use a two by four laying on top of these to mark the rest of the piers so they can be cut to the right height. As long as your 2×4 is not warped this will give a far more accurate measure than trying to do so by measuring each post.

At the same time, if you are using pre-made concrete piers, you will still need to do the same thing to make sure your shed will be level once it is set in place.

Attaching the Foundation

The last part involves creating the final foundation for your shed to sit on. There are two ways you can attach the 4×4 framework to the piers. One is to use metal over the top straps, the other is to uses metal mending plates. Both can be used to bolt the pier to the foundation runner.

DO NOT attempt to simply screw the foundation runners to the piers as this type of junction will not provide the necessary amount of structural strength.

pier_foundation_frameImage courtesy of Artistic Wood Products

The 4x4s are the basis upon which you will be building the rest of the foundation for your shed to sit on.

All that is left now is for you to build the framework upon which your shed will be laid to rest. Follow the instructions that came with your shed or see our tutorial on building frameworks for your shed to sit on.

Down to the Last Pier

Which type of pier shed foundation you choose should be based on the land you have to work with, your budget, and how comfortable you are with this type of construction work. Personally, when I built the pier foundation for my shed, I started from scratch with several lengths of pressure treated 4x4s, a load of gravel, and several bags of pre-mixed cement. In the end, I believe this type of pier shed foundation provides the strongest base for most sheds.

I hope this information has been useful to you and helps you decide which type of shed pier foundation to build for your shed.

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Gravel Shed Foundation

How to Lay a Gravel Shed Foundation

A gravel shed foundation - different sized gravel fills in all the gaps to stop water hanging around

THE MOST POPULAR FOUNDATION material for a shed is gravel. It's easy to work with, lasts virtually forever, is environmentally friendly, and most of all a gravel foundation will provide exceptional support for your shed.

More importantly, most of today's shed manufacturers recommend you build a gravel shed foundation before they deliver your shed to you. Here are three very important reasons why you should plan on building a gravel pad for your new shed:

Load Carrying Ability

One of the reasons a gravel foundation is one of the most popular choices for garden sheds, is that it allows you to spread the weight of your shed and everything it in over the surface of the entire foundation. Other forms of shed foundation such as concrete piers focus all of the weight on smaller areas putting more stress on the framework of your shed, increasing the risk of significant damage.

Level Ground

Even if your backyard is not level or has a small amount of slope to it, a gravel pad gives you the opportunity to create a solid level base upon which to place your shed.  By using a wood frame, you can overcome a reasonable amount of slope.

Closer to the Ground

Concrete piers, wood frame foundations, even concrete slabs can raise the floor height of your shed more than you want. Trust me, there is nothing worse than trying to get a lawn mower or other heavy items in and out of a shed that is sitting too high. A gravel shed foundation lets you control the height of your shed and can even let you put your shed at ground level (or at least only slightly above it).

Should I Build a Retaining Wall or Go Free Form?

The next major decision is do you build retaining walls to hold the gravel in place or do you go crazy and make your foundation free form?

As we go through the rest of the process, I will go over the benefits of both forms of pad. Each has their own unique features and benefits. Some of this decision is based on the space you have to work with, the type of gravel you plan to use, and the quality of the ground in your backyard.

What Kind of Gravel Should You Use?

Let's face it, to most of us, gravel is nothing more than a bunch of crushed up rocks. And while to a certain extent this might be true, there is more to gravel than meets the eye. Gravel comes in a wide range of types and grades, each of which has their uses. There are two main categories of gravel:

The Best Types of Gravel to Use for Your Foundation

21A and 21B Gravel

Image courtesy Hacker Services LLC (ping pong ball used to show relative size)

There is little difference between these two types of gravel are minor, but for a gravel shed foundation, the 21A variety is the better choice. Often referred to as “1-inch crusher-run gravel” both of these types of gravel have other fine materials mixed in with them. This material helps to fill in the gaps between the larger gravel pieces making it a more stable foundation that will not settle once your shed is placed on it.

The Wrong Types of Gravel for Your Shed Foundation

Gravel, Stone and Crushed Concrete over 1″ (with no smaller bits)

larger gravel not suitable for shed foundationsImage courtesy Hacker Services LLC

Although these grades of gravel can be similar in size to 21A and 21B, they do not contain any fine materials to help fill in the gaps. This means there is nothing to help hold the gravel in place leaving it to shift around rather than settle into a firm foundation. On top of this, once you place your shed on the foundation, the gravel can still move around, allowing your shed to sink into the ground. This can also cause your shed to become unlevel, which can cause damage to the structure.

Got Wood?

gravel pad with timber frameImage courtesy

If you decide to build a retaining frame around your gravel shed foundation rather than go with a free-form foundation, it is important you use the right type of lumber for the structure. The temptation might be to use standard lumber such as 2x6s to save money, but this is a bad choice. You may also be tempted to use creosote coated lumber such as old railroad ties. As long as you have no intention of growing edible vegetables or fruit within 50 feet of your foundation, this might be okay.

The problem with this is that creosote contains a range of toxic chemicals that are known to be hazardous to your health. The reality is that you really shouldn't use this type of lumber anywhere near your garden. Standard lumber is not strong enough, nor will it (as I found out the hard way) last very long once you bury it in the ground.

The best choice for building the framework around your gravel shed foundation is pressure treated lumber such as 4x4s or 6x6s. Not only will they provide you with a much stronger framework, being pressure treated will help ensure they last for many years without rotting and allowing the gravel to spread out, letting your shed down gradually.

Pinning the Timbers in Place

If you plan to build a framework out of timbers, they must be anchored in place before you pour the gravel into your form. If you plan to use a single layer of timbers, you can use lengths of rebar to secure them in place. However, if you need to use more than one layer of timbers, you should use galvanized spikes.

These are available in a variety of lengths to meet your needs at your local hardware superstore. Be sure to buy spikes that are long enough to go through the number of boards you plan to use and then at least 12 inches into the ground to ensure the timbers stay in place.

What Tools Do You Need?

Just like any other major project you plan to undertake in your garden, there are a certain number of tools needed to build a gravel shed foundation. Among these are:

  • Shovel – There is lots of digging to be done
  • Spirit Level – to ensure your finished shed is perfectly level
  • Leather Gloves – to protect your hands
  • Circular Saw – to cut the timbers to size
  • Tape measure – for obvious reasons
  • Small Sledge Hammer – to set the timbers and drive the spikes and rebar into place
  • Vibrating Compactor – to compact the gravel in place before placing your shed

Let's Build a Gravel Shed Foundation

Now that I have gone over the basics regarding the materials you are likely to need, the next step is to go over building your gravel shed foundation one step at a time, starting with building a retaining wall.

Retaining Wall Construction

In order to determine how much timber it will take to build the retaining wall, you need to know the overall size of your shed and then add three feet to both the width and the length. This will provide you with enough room for your shed and an extended footer around it to help keep water from getting in it.

Mark Your Territory

Start by marking one corner of your shed with a stake and then mark the other three with stakes. Be sure you have added the required extra space. One way to be sure the stakes are set at the right spots is to measure diagonally between pairs of corners. Much like an equilateral triangle, these measurements should be the same.

Level the Ground

Using level find the lowest corner of the ground you plan to use and cut a trench into the ground that goes all the way around the perimeter of your shed. Bear in mind your timbers should be inside the lines created by the stakes you have driven into the ground. (Be sure you use the level to ensure the trench is perfectly level all the way around.

Start Building

Start out by laying your first layer of timbers in the trench. Next drill several holes through each board and secure them to the ground using rebar or galvanized spikes.

Add More Timbers

Wherever necessary, add in extra timbers offsetting each corner in much the same manner used in the construction of a log home. This will help to keep the timbers in place. Now secure the timbers together using galvanized spikes spaced out every two to three feet driven into the timber below.

Phase Two – Break Out the Shovel

Now comes the fun part, you have a hole in the ground inside the timbers for your gravel shed foundation, the only problem is that it is still full of dirt.

Getting Started

Grab a shovel a pair of gloves and a wheelbarrow to haul away the extra soil.

Start Digging

Depending on the size of your shed, you have a lot of soil to remove. So, put on your leather gloves, grab that shovel, and put it to work. You will need to remove enough soil to lower the level of the ground inside the frame you just finished building until it is at least four inches lower at its highest point below the top of the highest timber.

Add the Gravel

Finally, it's time to add in the gravel. Be sure you are using 21A or at least 21B gravel. Pour in no more than a 4-inch layer and then use the vibrating compactor to compact the gravel firmly in place. This ensures it won't continue to settle once you have your shed in place.

Make a Screed

Use a “screed” (which is a fancy name for a length of wood that reaches from one side of your timber frame to the other) to level the top of the gravel shed foundation. The screed will help reduce the high spots in your gravel by moving the excess gravel into the low spots, filling them in.

Layer by Layer

Continue doing this until the layer of gravel is level with or slightly below the top of your timbers.


You have just finished building your first gravel shed foundation. Now all you need to do is install your shed and fill it with everything that goes with it.

Building a Free Form Gravel Shed Foundation

The only time you should consider building a free-form foundation for your shed is if the ground you plan to put it on is perfectly flat. If you try to use this type of foundation on sloping ground, there is the distinct possibility that the ground under your foundation will erode out from underneath it.

No matter whether you plan to build your free-form foundation on flat ground or a slope, be sure the gravel pad you create is approximately 18 inches bigger on all four sides than your shed. Doing this will allow for a certain amount of corrosion to occur without affecting the stability of your shed.

Start with Level Ground

On a level piece of ground, mark out the corners of your gravel shed foundation allowing for at least 12 inches on each side. Thus, if you have an 8 x 10 shed, your stakes should be set to create a space that measures 10 x 12 feet.

Grab Your Favorite Shovel

It's that time again, grab your gloves and favorite shovel. Remove the top four inches of sod and soil from the space between the markers.

Create a Temporary Frame

Using a number of 2x4s build a temporary framework around the sides of your foundation hole and stake them in place. You can use the stakes and timbers to create a level frame and set the height of the foundation.

Fill the Hole

Fill the hole in with gravel and use a screed to level off the gravel.

Compact the Gravel

Using a Compactor to compact a gravel driveway

Use a vibrating compactor to compact the gravel add more gravel to the foundation until you have a pad that is perfectly level and well compacted, then remove the temporary framework.


Once again, congratulations you have built a gravel shed foundation ready to install your new shed in place.


Here's a quick video of the process of preparing a gravel pad for your shed.

Important Notes

There are a few important notes you should be aware of before getting started.

  1. Never build your gravel shed foundation off level, the shed delivery people will only have to level it before they drop off your shed or you will before you can build on the pad.
  2. You can't get away with simply dumping the gravel on the ground and spreading it around with a rake, as this will not create a level foundation for your shed.
  3. Put the gravel down in layers and compact it in between each layer (stick to 4-inch layers). If you don't do this, the gravel will continue to settle after you put the shed on it.
  4. Use the right type of gravel, avoid pea gravel as this type of gravel cannot be properly compacted.
  5. If you plan to add a concrete pad over the gravel foundation, you must dig down at least 8 inches to allow for 4 inches of gravel and 4 inches of poured concrete.
  6. If you plan to add pavers to the top of the gravel, dig down at least 8 inches to allow for the thickness of the pavers and that sand layer you must build between the gravel and the pavers. The sand gives the pavers something to settle into that will help hold them in place and a bed that will ensure they won't crack.


Building a gravel shed foundation does involve a fair amount of hard work. But, the most important thing you need to keep in mind, is that whether you build a framed in foundation or a free-form one, it has to be as close to perfectly level as possible before you put your shed on it. If not, you face the possibility of soil erosion that could end up damaging your shed. I hope this information helps you create the perfect gravel foundation for your garden shed.

If you need more information why not join a Facebook group or check out the many projects on Pinterest.


The Best Plastic Shed Base for Your New Shed


The Best Plastic Shed Base for Your New Shed


There are 3 decisions to make about shed alarms and keeping intruders out of your shed

MAKING THE DECISION to add a shed to your garden comes with a host of questions that must be answered before you get started.

One of the more common questions concerns to be whether you need a base for your shed.

While you could simply drop your shed on the ground, this may not be your best option.

From a simple plastic shed base to a concrete slab, your shed is going to last longer if it is not left sitting flat on the ground.

The Advantages of a Shed Base

So let's start by thinking about building your brand new shed directly on the ground. Even if you take the time to remove the grass and flatten the dirt, over time the soil will erode and shift.

When this happens, your shed floor is no longer going to be sitting on a flat surface. This can cause the floor to warp or have hollow spots under it that won't be able to support any weight, causing damage to the floor.

If you have a wood or metal shed, the damp from the ground will slowly seep into the wood or onto the metal. This leads to rot and rust that will in time destroy your shed. The more it rains or snows, the more unstable the soil is likely to become, leaving your shed unsafe and insecure.

If your shed does not have a built-in floor, this becomes even more of a problem. These sheds require some form of concrete, wood, or plastic shed base that they can be anchored to.

A Firm Foundation

The right shed base will provide your shed with a firm foundation, much like that under your house, that will help it remain properly leveled.

This means you should never have to worry about your shed becoming out of square, which can have an adverse effect on how well the doors and windows work.

On top of this, a good concrete, wood, or plastic shed base will help keep your shed up and away from the ground and from the risk of water puddling around the bottom of the walls.

Let's Talk More about Plastic Sheds

Whether you are building a plastic shed from panels, a metal shed, or a wood one, it needs to be sitting on some form of level surface if you want all the panels to fit correctly. If the surface is not level, the panels may not line up leaving gaps that are only going to let rain and snow into your shed.

This is especially true for plastic sheds as many of the kits are designed with panels that simply snap together. If the foundation is not perfectly flat, the panels may be pulled apart or warp out of shape.

While a wood or metal shed is likely to have walls that are heavily reinforced and as such not likely to warp, this is not the case with most plastic sheds. The typical plastic shed features single or double layer walls made of flexible polyethylene resin.

Some feature steel rods or frames for extra strength, but these panels are not made to take on the stress of sitting on uneven ground.

The same holds true for the roof panels, they are designed to fit properly and remain watertight only when the entire shed is sitting as close to perfectly level as possible. The only way to actually achieve this is by putting your shed on a good solid foundation such as a plastic shed base.

One thing to keep in mind is that even if your base is slightly off kilter, you can always use thin strips of wood between it and your shed walls to adjust things for a perfect fit.

My Plastic Shed has a Floor

When you were looking at the many different brands and styles of plastic shed, you probably found that most of them come with some form of plastic floor. However, this is not always the case, so be sure the shed you finally decide on has a floor.

At the same time, it is very important for you to understand that the plastic floor that comes with your shed is not a base or foundation. It is only a floor and as such is only as good as the surface it is sitting on.

Lifetime 6402 with Plastic Shed Floor

An Image of the Lifetime 6402 with Plastic Shed Floor. This isn't a shed base

If you don’t use some form of foundation such as a plastic shed base, your floor is not going to remain sitting flat on a supportive surface for very long. As the soil underneath, it erodes voids will form eliminating any support for the floor.

The floor may crack and break through in these areas or it may shift completely, leaving you with doors and windows that don't work.

The problem with most plastic floors is that they are hollow with minimal reinforcement in what the manufacturer deems to be “vital” spots. Even with this type of construction, the average plastic floor is not strong enough to last without a good solid foundation underneath it.

Different Types of Shed Base


A number of people start out placing their first shed on a gravel surface, thinking that this is going to provide them with a long-lasting firm base for it.

Stone Gravel texture background

There are several problems with this, starting with the fact that gravel is not a permanent firm surface. Over a relatively short period of time, the gravel will sink into the ground causing your shed to slowly become unstable and out of square.  

Gravel is also porous and can allow water to seep in. When this happens, the water can freeze causing an ice buildup that can and almost certainly will destroy your plastic shed floor.


Pavers are a step up from gravel alone, and are a good value way to provide a solid base for your shed. Pavers do have to be placed on a perfectly flat and level surface in order for them to be effective.

In many instances the installation process starts with level ground, followed by a gravel pad that is leveled, and then the pavers are installed. This forms a very solid foundation for your shed to sit on, but going through all three steps can prove to be somewhat costly.

Wood Base (Piers)

This type of shed base typically involves a number concrete molds into which you set 4 x 4 wood piers onto which the wood frame of the base is mounted. This type of base is designed to keep your shed up off the ground.


While this type of shed base framing can definitely create a very solid foundation for your shed. Wood, however, even pressure treated, is subject to rot and pest infestations including mice, rats, ants, and termites. Something well worth thinking about depending on where you live.


Concrete makes an excellent material for use a base for your shed, however, you will probably need to call in a professional to pour and form it.


When properly poured, concrete will provide you with a perfectly flat surface to anchor your shed to. In fact, you can have bolts installed into the concrete as it is being poured that you can use to anchor your shed.  

The most important thing to remember is that the slab must be perfectly level and flat for you to get the best results.

Now for the Plastic Shed Base

When it comes to choosing a base for my latest plastic shed, I knew I needed something that was going to provide a solid strong foundation, be resistant to most forms or rot or bug infestations.

I also wanted a base that was relatively easy to put together, affordable, and environmentally friendly. Enter the plastic shed base, my personal choice.

With a little research, you will see that there are several different brands and styles to choose from. Some such as the “Ecobase” brand use thinner plastics that range from 3 to 6 millimeters in thickness, others as “HawklLok or Forest Plastic Base” are much sturdier.

These use thicker plastics and are built from multiple plastic pads that are designed to physically lock together. When assembled, these bases form a completed pad that is almost as strong as a poured concrete pad.

The Benefits of Plastic Shed Bases

There are many benefits associated with plastic shed bases, starting with the simple fact they are not very heavy. These bases are great for anyone who doesn't want to risk messing up their back.

Not only are they less stressful to work with, but you can get the whole family involved in building them and make a fun family day out of the project.

Among the other benefits of plastic shed bases are:

  • Since your shed will be sitting directly on top of the plastic grid, this will make it much harder for pests such as rodents to get into your shed. That is unless they gnaw a hole in the floor.
  • If you are using a plastic shed base that forms a grid, the gravel that you place in between the grids will help to keep rainwater from splashing onto the bottom of your shed. This is very important if you have a wood shed as all the water will only serve to accelerate rot.
  • The gridwork forms a very solid foundation, especially when packed with gravel for any type of shed, including those with plastic floors.
  • The pad style plastic shed base, when laid on a solid level surface can produce a base that is almost as strong and supportive as a poured concrete.
  • Most plastic shed bases are made from recycled plastics that can be fully recycled once you are finished with it. These plastics are very eco-friendly and made to last for many years without rotting.
  • The plastic resins are designed to be resistant to the sun's UV rays, ensuring they do not become brittle as many other plastics are likely to.
  • Plastics do not hold moisture in like concrete or wood will, thus they will not sweat leading to rot or rust if you have a metal or wood shed.

These are only a few of the benefits of plastic shed bases. For me, I based my decision on all the above and the fact I had a short timetable to work with.

The fact that most plastic shed bases are relatively simple and quick to assemble is perhaps one of the most important benefits.

Here is the Plastic Shed Base I Picked

8 x CrazyGadget GRASS GRID

A British Made Superior Quality Plastic Shed Base

This eight-piece plastic shed base kit can be used to create a base large enough for a 6 x 6 shed. Each square measures approximately 18 x 18 inches.

Each piece is designed to interlock to form a much stronger final assembly. If your shed is larger than eight pieces, you can always do what I did and buy more than one kit.

Once you have the final assembly put together, you should fill the grid in with pea gravel to form a sturdy base for any type of shed, wood, metal, or plastic. The heavy-duty plastic used to craft the gridwork is UV resistant and made to last for years.

One more great thing about these grids is that they are strong enough to handle the weight of your car, truck, or SUV and can be used to help hold the gravel of your driveway in place if you have any left over.




Needs gravel for maximum stability


Built to metric sizes may not be an exact match for standard size sheds

Easy to assemble

No built-in anchor spots for your shed

Other Options Worth Considering

If you are still not sure whether or not one of the various plastic shed bases are the right choice for you, perhaps you might want to consider contacting your shed's manufacturer.

Many of them offer their own shed base kits. These shed base kits should come with everything you are likely to need to build the base and then secure your shed in place.

A perfect example of this are the shed base kits made by Arrow Sheds for their sheds. These kits contain all of the HDG steel frame pieces needed to build the base along with the required hardware.

These kits are self-squaring by design for the ultimate in easy assembly. You and add a flooring material of your choice to them or simply bolt the shed directly on the frame.

While they are made for Arrow brand sheds, there is no reason why you couldn't adapt them to fit your particular brand of shed.

In Conclusion

If you are going to invest the money and time in building a shed for your garden, plastic or otherwise, you owe it to yourself to invest in a good solid foundation for it.

Given the relatively low cost of plastic shed floors, there simply is no excuse for not putting your shed on a good solid foundation. The plastic shed base above is the best one I could find and as I have found out, more than up to the task of supporting your shed and everything you plan to put in it and best of all its simple to assemble.

The grid style system is exceptionally strong when filled with gravel or cement and you can use “U” bolts to secure your plastic shed in place. If you live in an area of high wind, you can use anchors to hold the base to the ground for added security. Mine has been in place for several years now and has not budged an inch.

I hope you have enjoyed reading this and the information I have put together for you will help you find the perfect shed base, plastic or otherwise.

If you liked what I have put together for you here, please let me know.

Let everyone know you enjoyed reading this on Facebook, Twitter, and Pinterest.

Thank you for reading this.

Related Articles:

How To Pour A Concrete Slab For A Shed

How to Pour A Concrete Slab For A Shed - Finished Slab

A CONCRETE SLAB is one of the more expensive ways to prepare your site. However, if done correctly it can also be the best. A slab will keep the shed level and prevent grass and weeds from growing both under and around your shed.

It's also the best to work on, the strongest and longest lasting foundation for a shed. So if you like to only do something once, then this is the foundation for you.

If your still unsure, we have compared the different shed foundations against each other here. Otherwise let's get started!



You will need to check with your local government about pouring your slab, regarding your local laws.


Tools You'll Need

Tape MeasureMarker PenHardwood Pegs
Mallet/HammerLengths of TimberScrews & Drill/Nails & Hammer
Wheelbarrow(s)Spade/Shovel72 Inch Level/Straightedge
Masonry String LineString Line Level/Laser-LevelHose Connector & Hose
Concrete Hand Tools


Materials You'll Need

Steel MeshBar-Chairs
Builders Plastic (Maybe)


Planning for your Slab

The first step is to mark out the size of your slab. Measure off something (the fence or side of your house) and use that as a reference point.

Once you have the size, grab your hardwood pegs and stick them into the ground at the corners. Put them in firmly because you'll be digging around them later.

When you have the size, you need to get the desired height. The two most popular ways to do this are:

1. Run some stakes and a string-line at your desired height. Then use a level string level to get the height right the rest of the way around (Note mark the stakes with a marker after you have got everything where you want it. Just in case someone steps on the string)

2. A laser level – You still need to use pegs with a laser level to have something to mark. When you've marked all your pegs, grab out your string-line and run it around all of your marks.


How Much Concrete?

At this stage it's a good idea to work out how much concrete your going to need. A few simple calculations will help here. LxWxH. Seeing you know your Length and Width, you can adjust your height if you need to, to match how much concrete you are ordering.

In my experience, ordering concrete from a mini-mix comes in a minimum of 1 cubic meter. The size of my slab is approx 3.4m x 2.3m.  Multiplying this by .125 (12.5cm) gave me .9775 cubic meters which is very close. A little too close for my liking. We ended up digging the hole 14cm deep, added 2cm of gravel and only had a spadeful of concrete left at the end!

It's always best to have more and not want it than the other way around, so keep playing with the figures until you have 5-10% extra, just in case.

If your slab is large then you shouldn't have this problem. Just add 10% onto whatever your cubic meter figure came in as, then order that.


Mark Out The Slab

It's almost time to dig your hole.

But first we need to work out how deep to dig your hole. Your concrete slab should be at least 4 inches deep (100mm). But you should also allow some room for the gravel.

The gravel will help the concrete sit on something a bit firmer than dirt and the gravel will compress to make a base that is quite hard.

Depending on how much gravel you have/order you might want to leave 1/2inch to 1 inch (10-25mm)

For my example, we had about 1/5th of a cubic meter in gravel. This gave us the 2cm across the bottom that we wanted.

So far you should know how deep you need your hole to be for the concrete (LxWxH= the amount of concrete you have – 5-10%)

& the extra depth you need in your hole to allow for the gravel.


Dig Your Hole

Make sure the bottom is flat and the height is all uniform all the way around.

Dig a little outside your perimeter, this will give you room to place your form-work later.

After you have dug your hole, water it. This will help the dirt settle.



String-Line and Form-WorkThe form-work here is in place and screwed together. The back fence acts as the form-work at the back, while the builders plastic holds the concrete in

Next step is to ‘box off' or make some form-work.

Form-work is the container for your concrete slab. Kind of like how a glass keeps water in it, the form-work keeps the concrete in it.

If your slab is going to be 4 inches (100mm) then it helps to have at 4 inch timber for your formwork. If you don't you will need to use the builders plastic on the inside and run some dirt up to the form-work so the concrete doesn't spill out. It also helps to staple the builders plastic to the form-work so it doesn't move.

Screw or nail your formwork together at the edges, then use your hardwood pegs to keep it in place. Over long stretches the timber might bow, so use the pegs on either side to keep it straight. (When you are pouring your slab, the concrete will try to push the form-work out. That's when you take the inside pegs out.)

Once the form-work is in, then you can remove the string-line. The top of the form-work should be the top of your slab, where the string-line was. If your timber is straight and true, then you can remove the string-line before you put the form-work down.



Once the form-work is down and secured its time to put the gravel in.

Put it in as even as you can, while keep watching your heights around your form-work.

TIP – after the gravel is down, water it. This will help the gravel condense and stop the dust from blowing everywhere. It is also a good idea to water the gravel just before you put the slab down.


Steel Mesh

Steel MeshThe steel mesh covers almost all of the area of the slab. The bar-chairs are in place and need to be stood up.

Before the concrete comes, or gets made we need to have the mesh ready to go.

The mesh is going to be different depending on your use for the shed. If your shed is like mine (just a tool shed) then you wont need any heavy steel. Standard (thick mesh) will do.

However, if you want to put your car in here then you will need some stronger steel. 1/4 inch bar run where you are going to park your car, and anywhere the car is going to get driven over (like a driveway) is a must. And you will also need some mesh to cover the rest of the slab.

The easiest way to cut this is with special cutters, but you can use an angle grinder (recommended) or a hacksaw (not recommended) if you are really stuck.

When cutting the steel mesh you want to leave it at least 4 inches from any side. Having steel poking out of a slab is bad. It will rust and get into the concrete which will cause concrete cancer (your slab will slowly crumble from the inside.)

The mesh also shouldn't sit on the ground. it should be suspended in the slab, and the easiest way to do this is ‘bar chairs'. You could also get some old bricks or something else concrete and put them under the slab, but the bar chairs are quite cheap, and wherever you got the mesh will sell them. You can also set them at different heights which can come in handy


Checklist so far

☑ Form-work level, and at correct height.

☑ Form-work is strong

☑ No gaps in form-work for concrete to escape

☑ Mesh in and at least 4 inches in from form-work around all sides

☑ Mesh raised to about the center height of slab


Concrete Pouring Day

TIP – Don't do this on your own if you can avoid it. On a hot day time can be against you so having two people means the job gets done a lot faster.

TIP – Wet everything you are going to use in the concrete first. Your level, shovel, etc. this will make cleaning up a lot easier, the concrete doesn't stick as much to wet items.

The easiest way is to get concrete delivered. That way you just run your wheelbarrows to and from the mixer truck and dump them as evenly as possible.

If you have hired a small mixer and bought the materials you will need to get the mix correct, and there are other things you have to worry about. And I don't think its any cheaper

As of writing this, the concrete for my slab cost me $225 AUD delivered. I'm sure if you Googled concrete mini mix in your area you could get some quotes.



1st thing, get out and water that gravel – you'll also need a hose nearby for later.

It's also a good time to get all your tools ready for later on so there's no mucking around. Like your hand tools, straightedge/level etc.


Spread The Concrete

Start dumping your concrete as evenly as you can. Make sure that the form-work doesn't get damaged. (We used an old board and a few bricks to create a ramp that went over the form-work)

Firstly use your shovels to move the concrete around. Don't be afraid to poke and prod, because that will help get any air bubbles out. The pros use vibration tools on big sites to do the same job.


This video shows how they pour and level a concrete slab on a commercial scale


Leveling Your Concrete Slab

Then get in and start evening it out.

Serious landscapers have a huge straight edge which they use to level off concrete. You can get away with a long level (2m)

The best way I've seen to even out concrete is start at the back and work your way forward. With the level or straight edge, rock it forward and back in your hands until you can sit it on the concrete and get a flat surface. This may take a couple of times so be patient!

It's important to get the bit you are working on right, then move on.


Once It's Flat and Level

Once the slab is flat, and you are happy with it it's time to clean your tools that you have used.

As your working, you will see the water start to rise to the top of the slab, this means it is starting to dry.


Concrete Finishes

Concrete finishes should be applied when the top of the concrete is semi dry. After you pour the slab and level it the water will rise to the top. This gives a glossy type look to the concrete. After this has died down, and the water has evaporated a little then it's time to put on your finishes. The time it takes for this to happen varies on the temperature, and how much sunlight is on the concrete. On a coolish day with shade over the concrete it can take a few hours to get to this stage.

Finished Slab

The slab in the picture is finished with a screet finish. This isn't necessary, you do need a trowel to be able to do this, (something like this) however the corners are rounded off, which i recommend. (will save the edges from chipping later)

To do this you go around the end with a special tool. If your half decent with metal work you could make one yourself, or you can just get one from your local hardware store or online here. To use it just stick it in between the slab and the form-work and let the tool do the rest. You need to go up and down a few times. As you can see on my slab the corners are a little indented on the slab. It looks nice in my opinion.

There's one more thing we need to cover before the concrete starts drying and that is dummy joints.

How to pour a concrete slab for a shed - Dummy JointsOver time this concrete has moved, but still looks good because any cracks are concealed by the dummy joints

If you have a slab that is an L shape for example, you will want to put in a dummy joint. To put one in, you use a tool like this. It's a ‘Concrete Groover' and puts a groove in the concrete. To get a straight line, when you are doing your finishes put your level on the concrete and run the Groover along the level, like you draw a line with a ruler.

Running these dummy joints means if the concrete is going to crack, the crack will be restricted to the dummy joint. You can see where we put dummy joins in our driveway slab for reference.

TIP – If your slab is too big and you can't finish it by standing on the side and reaching in, you might need to invest in some kneeler board pads (like these). They displace your weight over the concrete keeping it flat and level whilst it hasn't dried. This way you can reach over and put your finish and dummy joints in.


24 Hours After Pouring

You want to be pouring on a nice day, but sometimes rain can be forecast. If rain is forecast on your day, then it's a good idea to cover your slab with something. We used builders plastic and stapled it to the fence.

You could use tent poles or anyhting that you have as a makeshift shelter. It is best of course to try and avoid these days.

After 24 hours you can walk on your slab, although it will take about 1 month for your slab to ‘fully harden' (apparently it took the hoover dam 2 years to fully harden).

If your just building a shed on it, you can start doing that in 2 weeks. Although i would keep my car off of it for the full month.


Thanks for reading,. Any questions, comments or queries on how to pour a concrete slab for a shed then please use the contact us page!

The 6 Most Popular Shed Foundations – Reviewed

Making a strong start…

We think foundations are a very important part of your new shed. Why are foundations so important? THE FOUNDATION SUPPORTS THE WALLS, and the walls support the roof of the shed. And the supported roof is why you are building a shed in the first place!

This makes choosing the right foundation important. If you get it wrong, you get a sloping shed which is ugly and sticks out like a sore thumb.

And besides, no one wants their beer to slide off the shelf in their shed. It's not a good look in front of the neighbors.

Foundations are also a pain in the butt to fix; it usually involves getting unnecessarily dirty. So IT'S NOT SOMETHING YOU WANT TO DO TWICE.

Because it’s so vital, to make deciding easy we’ve sorted shed foundations by what’s important.

This way your shed will stand the test of time… upright.

Bad foundations are good as a tourist attraction, but not for your shed

*some counties and cities have regulations regarding shed foundations. Check out where you stand before beginning your build here.

Reveal Comparison Table

Flat Ground

Why not just stick it straight on the ground?

Although it is definitely the quickest and cheapest option, sticking your shed straight on the dirt definitely has its cons.

Firstly the exposed dirt will make the things in your shed dirty, and WATER WILL ALSO SEEP THROUGH THE GROUND and make the dirt floor of your shed wet. This moisture will lead to rot and corrosion which will wear away at the shed over time.

Metal and plastic sheds that are put on the ground are typically fixed with metal stakes or tent pegs through the sidewalls of the shed. The longer the anchor, the better the stability of it.

FABRIC SHEDS ARE DESIGNED TO SIT ON DIRT and come with all the necessary anchors. The fabric construction is forgiving of movement whereas more rigid materials (wood, metal, plastic) are not.


Because the uneven nature of typical yards, putting a shed straight on the ground can affect how the panels fit together, and how the doors and windows work. This ultimately LEADS TO A SHORTER LIFE FOR YOUR SHED

Quickest option Shed will corrode and rot
Cheapest option Expect grass and weeds
  Doors wont work properly


Looking for low cost and easy to do?

Stone Gravel texture backgroundGravel is an easy solution for a shed base, and works well with small to medium sized storage sheds, particularly metal, plastic and fabric ones. If you have all the materials THE PROCESS SHOULDN'T TAKE MORE THAN 2 HOURS (depending on the size of your shed.)

All you need to do is dig a hole the same footprint as your shed, and around 3 to 4 inches deep. Then pour the gravel or crushed rock in. As you pour the gravel in, you will want to keep pressing it down by stepping on it or using something heavy to apply that downward pressure.

You can attach your shed directly to the gravel with pegs or auger anchors (the longer the better). This is definitely the easier option, although gravel bases also provide support with other foundations, such as a wooden frame, or concrete slab.

How to Lay a Gravel Foundation


MUCH BETTER THAN STRAIGHT GROUND, but also does have its disadvantages.

Low cost Can make equipment dirty
Easy to do Gets quite cold
Provides a stable flat surface Can get wet inside

Want to put in a gravel shed foundation? Here is how you do it

Arrow shed foundationKit from manufacturer

Already thought out for you…

Some sheds can be built with a supplied (or added extra) foundation kit. These kits can go on gravel, but typically they get put straight on the ground.

The KITS DO NEED TO BE INSTALLED ON A FLAT, LEVEL SURFACE (so that the panels fit together and the doors work). They do work best on flat surfaces; altering these kits to a sloped surface can be hard work, harder than its worth.

If you are going to use a kit, be warned that you may have to purchase some added extras. Arrow sells a floor kit that requires you to provide the cut plywood for example, so if you’re on a budget, using a kit may cost more than its list price.

Kits (such as these) also come in many different sizes so pick the one that is right for your shed size.

Should You Use a Kit Foundation?


An easy, tailored solution for your storage shed.  IT SHOULD TAKE YOU ABOUT 2 HOURS TO ASSEMBLE YOUR KIT.

Specially made for your shed Added extras
Cost effective Needs level ground
Easy to assemble  


A great way to get a strong base, quick and cheap.

Installation of paving slabsYou can buy large pavers from hardware stores like Home Depot and Lowes. Once you have got everything you need, you can LAY YOUR PAVER FOUNDATION IN LESS THAN 2 HOURS.

All you need to do is put some gravel or brickies sand down and level off the area. Then place some plastic down to help waterproof your shed, then lay your pavers on top. To secure the shed, simply dyna-bolt the shed down to the pavers.

Pavers also prefer a gravel base, but can go straight on flat, level ground. Putting a layer of gravel down first will stop the pavers from sinking over time. Smaller pavers are more susceptible to sinking than larger pavers.

How to Lay a Paver Foundation for a Shed


Pavers work best for smaller, storage type sheds. The benefit is that they keep your equipment off the dirt and they are very durable. ONCE THEY ARE DOWN, THEY WILL STAY DOWN.

Easy and quick to lay Can sink over time
Easy to secure shed to pavers Not for larger sheds

Here's a step-by-step guide to laying a paver shed foundation

FIND OUT HOW to keep your shed foundation waterproof and keep the water from seeping into your shed with our simple 3 page report. Mail Subscribers receive it free. Download here.

Timber frame / Piers

The carpenters choice

Timber Frame for shed

An example of a timber frame on piers

Timber frame bases are quite popular for sheds. They are easy to put together, PROVIDE A STRONG PLATFORM, and are relatively easy to level.

Your frames must be made from lumber for outdoor use. Treated pine and cedar are two that come to mind. Once you have the correct lumber, BUILDING THE FRAME IS EASY. All you need to do is cut it to size, and screw it together.

Timber frames can sit straight on the ground, although it is not recommended. There are a 2 main ways that timber frames sit on the ground; Piers and Pavers.


How to Setup a Pier Foundation

Piers are supports that are dug into the ground and set to a common, level height. The frame then sits above the ground.

To strengthen piers, you can concrete them into the ground. This helps spread the load and adds longevity to the foundation.

The big draw card for piers is that the shed is above the ground so it is kept dry at all times. It can however, take a little time to set up the piers properly. But per square foot it is a cheaper option than a concrete slab.

Want more info on piers? Here is an article on how to install a pier foundation

Shed Pier Blocks

An easier way to use piers to support your wooden frame is to use these purpose made timber frame holders


Pavers can be used to level up a shed and work quite well. They can be a cheap solution, especially when you have some lying around the yard. They are a quicker and easier solution than piers, and can be moved later. The downside is that it is hard to fix the frame to the pavers.


Timber frames are a very popular way of supporting a shed. They are STRONG, GOOD VALUE, AND RELATIVELY EASY TO ASSEMBLE.

Strong foundation Piers are time and money intensive
Easy to build Pavers are hard to secure to the ground
Durable if right lumber is used  


Concrete Slab
Strong, flat and level…

Laying a cement floorConcrete is a strong, flat base for a shed. Its weight also helps KEEP THE SHED SECURED TO THE GROUND.

It is commonly used for houses, factories and large warehouses. It is good to work on and provides a strong base to attach the shed walls and anything else you want to.

If you are thinking of using a concrete foundation then you will have to plan it ahead of time. Concrete takes at least a month to fully set, although it will be ready to work on after 5-7 days.

You can do it yourself, although a landscaper, builder or concreters experience will help. We recommend that you will use 25Mpa concrete with some steel reinforcing mesh to help hold it together. Start to finish (not including drying time) WILL TAKE YOU AROUND 4 – 6 HOURS.

How to Pour a Concrete Slab Foundation


In our opinion, THE BEST FOUNDATION FOR ANY SHED, provided you have the time and funds.

Very strong A little costly
Durable Can take some experience/expertise
Easy to customize to your own needs Takes time to set

Click here for more information on pouring a concrete slab for a shed

Thanks for reading.

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