How to Build a Shed Foundation

how to build a shed foundation

When you are building a shed, whether from scratch, installing a premade one or building one from the kit the foundation is the key to whether your project will be a success or not.

Foundations for sheds are as varied as the individuals, type of shed, and the environment in which the shed is being constructed.

Today in this article, ‘How To Build A Shed Foundation’, we are going to look at various styles of foundations and then you can select the one that best suits your temperament or the area in which you are building.

We will look at wood foundations, concrete pad, stamped concrete, paver tiles, gravel, and concrete blocks. You can then choose from the selection the type of foundation that you want.

After you are done reading this article, you will be able to construct your shed in the location of your choice and ensure that is on an even keel as well as be able to support the weight of the items you wish to store inside the shed.

Wood Foundation


Wooden foundations are one of the easiest to construct. If you have access to some railroad ties this is an ideal solution.

You merely select the location you would like to have your shed to be and lay down to, 3, or 4 railroad ties equally spaced apart and then build the frame for the floor and fasten this to the railroad ties and then build upward.

If railroad ties are not available, 4 X 6s can be substituted. However, they should be treated or painted to resist wood rot and water damage prior to placing them.

2X4s also may be used, but they do not have the weight to ensure the shed remains stable in heavy wind. You, of course, can compensate for this by using more of them.

Wooden or Concrete Post


In this type of foundation, postholes are dug at strategic places and #10 cans filled with concrete are placed inside them and then leveled. This then allows you a firm surface to secure the frame and flooring of your shed.

An alternative method is to use 10 to 12 inch long and 6-8 inch diameter PVC tubing in place of the #10 cans. You can then level the tubes and then fill them with cement.

Another method is to place sawed off railroad ties or 4X6s sections into holes as well. Again rot and water damage is a possibility and you need make sure the wood is properly treated before using it as a post. You can also purchase round fence

Concrete Slab


This is probably the hardest foundation for the DIY amateur to construct, as it requires you to excavate an area larger than the proposed shed’s base.

The next thing you will want to do is build a wooden frame. Lay down a bed of gravel and tamp it into place inside this frame.

For additional strength, you might wish to lay down a layer of rebar over which you would then pour concrete into the frame and smooth it by hand.

After it dries, you might need to use a Concrete Sander to smooth out any irregularities.

This process can be time-consuming and may be best handled by having the work done by a remodeler or contractor.

However once in place this provides one of the sturdiest foundations you can have for your proposed shed.

Stamped Concrete


A relatively new technique is a more interesting approach to the tradition slab and that is to have a stamped concrete slab. With this type of foundation, pigmentation, and a pattern is impressed into the concrete prior to it being fully cured.

This enables you to put a pattern that can resemble almost any surface from marble to cobblestones, which gives your slab the appearance of much more expensive materials.

So, if you want a decorative floor for your shed or thinking of creating a patio with a shed on it this is an ideal solution to not only get the foundation for your shed but have an artistic and colorful patio as well.

A stamped concrete slab can be done as a DIY project. But again, as with the concrete slab mentioned earlier you might want to have the work of creating this type of foundation done professionally for best results.



In a gravel foundation, this is similar to laying a slab foundation in that you excavate an area to a depth of 3 to 6 inches.

Build a frame. Fill the frame with fine to medium gravel.

You tamp it down flat. Then you can either use railroad ties, 4X6s or build your shed directly on top of the gravel, as you desire.

Concrete Block

A concrete block foundation is similar to the post foundation mentioned earlier but uses concrete blocks spaced regularly to support the floor of your shed and add weight to hold it in place.

Either the blocks can be freestanding or as with the slab or gravel foundations, you can excavate the area where to blocks will rest then fill the area inside the blocks with earth, gravel, and/or sand.

Your shed then can be fastened on top of these blocks or left free standing.

How to build a shed foundation on uneven ground


Building on irregular surfaces can be a challenge. However, as you have read about the previous foundation techniques you see that they can be adapted to irregular surfaces quite easily.

By excavating out the area for your foundation and placing, a wooden frame down you can then create any number of the above-mentioned foundations as you choose.

In most cases, the concrete slab is the preferred choice. However, in the following section you will learn about another type of foundation that might even be equally useful and easier to build.

A Paver foundation


A Paver foundation is a versatile way of not only getting a foundation for your shed but creating a colorful patio as well.

As mentioned previously it is also a way to create a foundation in any irregularly surfaced area. You do this by excavating out an area that larger than the shed you are planning on building.

Next, install a wooden framework. You then lay down a base of sand and then fill the area with the pavers. Additional sand fills in any gaps between the Pavers.

This gives you a solid foundation for most sheds.

It also may be highly decorative combination patio and shed arrangement. This type of foundation can not only be functional and aesthetically pleasing, but increase the value of your property as well.

No Foundation?


Some sheds are prefabricated, which require no foundation at all and if you have a flat spot at the location, you want to put your shed this might be an ideal way to go about it.

This method simply requires that you assemble the shed at the location that you desire and by the weight of the items that you are, storing inside the shed ensures that the shed stays firmly in place.

This type of no foundation shed is usually found with the prefabricated vinyl, PVC, or plastic sheds. Some of the kits that you can purchase let you do this.

Both types of shed found at any of the home improvement centers such as Walmart, Home Depot, and Big R or ordered online as well also.

You however, could build your own shed from downloaded plans that can accomplish the same thing as well. However, these types of sheds run the risk of being susceptible to wood rot or blowing over if there is not sufficient weight within the structure itself to hold it in place.



Today you have learned about a few of the many foundations you can use in your shed’s construction.

Concrete slabs are the traditional method for creating a shed foundation. However, they are time-consuming and in some cases difficult for the unpracticed DIYer.

This is why other techniques such as posts, concrete blocks, or pavers offer a simpler solution to your foundation problems.

They wouldn’t foundation made up of old railroad ties or 4 by sixes offers another Avenue for you to explore as well.

You have also been shown a highly artistic way of using stamped concrete to not only provide for your shed’s foundation and floor but also creates a beautiful patio should combination that is perfect for outdoor activities such as grilling and outdoor parties.

Whichever foundation you choose, you now have a good of idea of what is needed to be done. You are also now aware that a foundation isn’t as big a mystery of as difficult as you may have one thought.

“Happy Building”

Please feel free to refer to our articles Build A ShedHow to Build A Shed DoorHow to Build a Shed Roof, and Shed Kits for Sale for more information about building a shed.