Sheds are great additions to your backyard, allowing for easy storage of gardening and general use tools that can’t find a place inside your home. And sure, the garage can be used for this, but also in most cases the garage is placed in front of a home, meaning the tools would always be away from the backyard where they would usually be the most useful. Besides, storing your things there will keep the space messy and cramped.

Hence, a shed is built. A tiny little cabin, sometimes not even big enough to house a person – just enough to keep your things safe and always within reach for when you need them.

However, just like a house, a shed needs a foundation to keep it safe and sturdy regardless of weather conditions or shifts in terrain. Today, let’s take a look at everything you need to know about building a shed foundation!

“Yesterday is not ours to recover, but tomorrow is ours to win or lose. – Lyndon B. Johnson

Check if you need a permit

Since sheds are not considered permanent structures, most places don’t even require a permit for it… but you should still check just to be sure. You don’t want any law trouble and headaches, after all.

You can check this with your local Building Department or HomeOwners Association, and when you do, be sure to specify the size of the shed you plan on building, since that can change the permits you may need to acquire. You can also take the inverse route and instead ask for more info on what types of shed need which permits, since that can influence your plan.

Some of the things that might influence the permit are the shed location, foundation type, the need for electricity and, of course, the size.

Do I need to build a foundation even for a small shed?

Very small sheds can be built without a foundation, but there are risks involved. The purpose of the foundation is to make sure your shed is protected from weather conditions (such as frost and flooding), as well as soil displacement and moisture that may allow for mold growth. 

If you choose to skip the foundation for a small shed, you should be aware that your shed will be extremely unprotected and won’t last long.

Pick a good location

When picking a good placement for your shed and shed foundation, there are some important elements to consider.

  • First and most importantly, when you check your local authorities about the permits, you should also inquire if there are placement restrictions. There may be rules regarding where you can place the shed in your backyard, so first learn those to make things easier for you.
  • Second, will you need electricity in your shed? If the answer is “yes, then you will need some extra work done to direct the necessary wiring to the shed. If you’re not sure how to proceed, a local electrician will be able to help you.
  • Finally, there’s the more practical side of things. Make sure you have enough space to open the doors and walk around it for convenience (but also for painting it once it’s built). 

And a very important note: a shed might look nice next to a large tree, but the tree roots can displace the soil over the years and cause problems for your shed, even if a foundation is built. Also, tree branches can fall on top of it, which is not good – so try to keep it away from large trees.

What’s a frostline and why is it important?

In areas where winter gets really frosty, local regulations will have a determined frostline you need to respect. The frostline is the depth at which water freezes in soil, which is important because depending on the season this means certains structures can move as the soil thaws. As you can imagine, this is crucial information for building your shed foundation!

About the types of shed foundation

There are several variations of shed foundations when it comes to structure and materials, but I’ll try to keep it simple.

First, shed foundation can be on-grade or frost-proof. On-grade foundations are easier to build as they stay more or less on level with the soil. Frost-proof foundations however are the preferred method for areas where the frostline must be respected, which means you’ll have to dig a bit deeper.

Frost-proof foundations are considered permanent, while on-grade foundations can still be removed in the future if necessary. This is an important distinction because permanent structures require permits.

Concrete shed foundation. Concrete slab foundation is widely considered the best shed foundation. It’s fairly well-priced, sturdy, and easy enough to build. Better yet, it works for on-grade and frost-proof foundations alike, though naturally, frost-proof will require more materials. Concrete can be poured into a frame to create a large slab, but it can also be laid as shed foundation blocks.

Wood shed foundation. Wood shed foundations are usually placed over concrete blocks to elevate it from the soil. It’s also an accessible shed foundation that’s not very demanding in labour and low on materials, though wood is naturally less resilient than concrete as it can have mold, crack, etc., it will still get the job done well.

Gravel shed foundation. This is probably the easiest type of shed foundation to install on your own, and it has the benefit of also being fairly cheap compared to the others. The downsides of gravel shed foundation is that it’s not recommended for slopes (even minor ones), and in case you have to respect frostlines, building piers to elevate it will still be necessary. However, for a level site where all you need is a simple foundation to get your shed built, gravel foundation is easy to install, economical, and fast.

What about slopes?

The best way to build sheds on slopes is to create a foundation like a deck using posts and footings. It’s not very common that a home will have such a sloped yard to require this, but if it does, this is the solution. The process isn’t very difficult and it’s much easier than digging into the slope and filling it with concrete or trying to level the site, for example.

Need help building a shed foundation? Get free quotes from foundation pros in your area today!


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