How to Build a Shed Foundation

If you are thinking about building your own backyard shed, you have many options and styles from which to choose.  But something you may not have considered is the type of shed foundation you need.  This is an important consideration for the DIY shed project, because it will determine many of the other possibilities you’ll need to consider.  As with any building project, it starts at the beginning, with the foundation.

This article is meant to cover the many types of shed foundations and how to build them.  After reading this page, you should have a good idea of:

• determining what kind of foundation your available space is suited for
• the types of building materials commonly used for shed foundations
• the ease with which each kind of shed foundation can be built, and the skill level needed
• the cost of different types of shed foundations
• the life expectancy, care and maintenance of types of shed foundations

We have provided links off the page for further instructions on building the foundations. Please make use of all the information provided. The more you know the better your experience building your shed will be.

Choosing the right materials for your shed foundation

Once you have an idea of the space, the shape and potential obstacles, you can make a wise choice with regard to the materials options available for your shed plans.  Here are a few of the most popular options:

• Wood $$ - By far the most flexible option, wood is easy to work with, requires the least amount of skill to construct, and with proper care and maintenance, will last for the lifetime of your shed.  If you have a sloped grade or tree roots, or rock obstructions where you plan to put your shed, a wood foundation is a perfect solution.  In most parts of the US, plan to anchor your foundation with wood poles set in concrete, in holes approximately 2 feet deep  Always use treated wood so that you will be protected from water and pest damage.  You can anchor your shed to a wood foundation platform that is larger than the area of the shed, so that you have a level surface for other kinds of uses. Here’s more information on building a shed foundation out of wood.
• Aluminum frame $ - Many shed kits use aluminum frames made from engineered aluminum, which screws together, is covered in plywood for flooring, and anchored to the ground using anchor bolts or screws.  Aluminum does not rust, so it can be placed directly in contact with the ground, and provides a sturdy foundation which will support the structure and the weight of the contents of any shed.  If you are choosing to build your own shed, engineered aluminum kits may not be a convenient option for you, however, since most of the commercially available aluminum foundation kits are designed to work within a manufacturer’s fastening system. Detailed instructions come with the kits.
• Concrete $$$ - This option is not for the faint of heart.  It requires a degree of skill and planning that may be outside of most laypersons’ comfort zone.  However, if you decide it is an appropriate choice, you will not be disappointed with the durability, relative care-free maintenance, and superior protection from the elements which concrete affords.  If you have a flat section of driveway, or an old concrete pad on your property which may have been the site of a previous shed, you may consider placing your shed there with confidence.  Be sure to use water-sealant caulking along the base of the structure, where it sits against the concrete, to ensure a proper watertight seal. Get some additional information on concrete foundations here.
• Brick or Concrete Pavers $$ – These sturdy and widely available flooring options serve shed owners well, but they do not provide much in the way of isolation from pests or the elements; particularly water.  There is not an easy way to seal the bottom of the structure in this type of foundation.  If you decide to use pavers or brick, be sure to lay a gravel substrate first, and fill in the gaps between the pavers with sand.  Things you store in this shed will sometimes develop mold or mildew issues, and pests often find their way in through the gaps and cracks, despite how careful you may be. For more information on this type of foundation click here.
• Concrete Blocks $$ - This is a great way to build a level surface on a sloped plot.  if you have never used brick mortar and leveled concrete blocks, you will want to read up on the best way to do it, but it is well within the reach of most DIY enthusiasts.  Concrete block pylons serve as the base for a wooden frame foundation. Here is some additional instructions on leveling your shed on concrete blocks. 
• Gravel bed or gravel rows $ - While not as attractive as some of the other options, it is often appropriate for ground that commonly stays saturated with precipitation for several days in a row.  This works best on level ground, when the ground can be graded, grass and roots and rocks removed, and the gravel can be spread and compacted to form a solid yet porous sub foundation. This is perfect for a smaller shed. Get more information.

If you are adding on to an existing shed there are additional considerations you will need to take. You might also need to build steps or a ramp for your shed for easy loading and unloading and we can help you with that as well.

Make sure you choose the right shed size before purchasing shed plans.