It depends on the size of your shed. Most sheds require a foundation. However, some very small sheds may not need a foundation.
The best way to answer the question “Do you need a foundation for a shed?” is to check with your specific shed manufacturer and your county codes or homeowners association (HOA) to find out exactly what is required for the shed you’re planning for.
3 key factors to consider when deciding whether or not to put your shed on a foundation are:
Size
Weight
Shed floor
What shed size needs a foundation?
The size of your shed is often what determines whether or not you need a foundation. Typically, any shed larger than 6×8 or 8×8 is going to require a foundation. However, a foundation is a good idea even for small sheds, because the right foundation, installed correctly, will protect your shed and extend the life and usability.
What shed weight needs a foundation?
In general, if the total weight of your shed is over 300-500lbs, it’s a good idea to place it on a foundation. It’s not only about the exact weight of your shed alone, but also about what you’ll be storing in your shed and the weight of those items that factor in here. If you’re going with a garage shed for storing farm tractors or cars and trucks, then you may want to go with a concrete pad. If you will be storing things like ATVs, lawn mowers, and motorcycles, then a gravel pad is usually fine.
For very small sheds, like those made by Rubbermaid, Lifetime, and similar brands, you may still want a gravel shed foundation if the total weight of the shed and contents is over 300-500lbs.
Does a shed with a built-in floor need a foundation?
Generally, any shed that comes with a floor should get a gravel pad 12” larger in each direction than the corner to corner exterior dimensions of the shed itself. Any shed that comes without a floor should get a concrete pad the same size as the corner to corner exterior measurements.
We’ll go into more detail later about how to figure out what size of gravel pad you should use and why concrete pads should not exceed the size of the shed resting on them. For now though, just remember that sheds with floors get oversized gravel foundations and sheds without floors get same-size concrete pads.
What dimensions should a shed foundation be compared to the shed?
This is a really common question and one that is worth digging into a little bit. If your shed has a built-in floor, you want the gravel foundation to be 1ft longer and 1ft wider than your shed wall dimensions (depending on shed model-contact us for details). If your shed does not have a floor, you want the concrete foundation pad to be exactly the same length and width as the walls of your shed.
A shed with a floor needs a larger, gravel foundation that will keep water away from where the walls meet the foundation. If water is allowed to pool and sit there for lengths of time, it will cause rot or rust and eventually ruin your shed. Gravel foundations prevent water from accumulating because any rain water is able to immediately drain through the stone. Water never pools, your shed retains its integrity, and your things stay dry.
Comments