With so many options for a shed foundation, how can you be sure what type of foundation is best for a shed? Read on to find out why Alan, an expert on metal sheds, recommends a gravel foundation for your storage shed.
Hi there! I’m Alan from Alan’s Factory Outlet. I’ve helped thousands of customers get custom sheds delivered and installed on their property, and I have learned from experience that a gravel foundation is almost always the best option for a shed foundation.
What is the Best Foundation for a Shed?
Occasionally my customers ask, “Isn’t concrete a better foundation than gravel for a shed?” If you were buying a garage to store a vehicle, you would almost certainly want to put the garage on a concrete pad. But you will probably use your shed to store mowers, garden supplies, and other household items. These types of things don’t need a concrete foundation. For a storage shed, gravel is almost always your best option.
One reason that gravel is better for a shed is cost: A concrete slab is much more expensive than a gravel pad. But the main reason I recommend a gravel foundation is to protect your shed from water damage. If you have a concrete foundation, water will rest on top. But a gravel pad will let water drain right through the foundation, helping protect your building. If your shed is frequently sitting in water, you shouldn’t expect your shed to have a long life of 40 years. You’ll be lucky if your shed lasts 20 years—and even that may be too optimistic, depending on how often it is resting in water.
How big should my shed foundation be?
I recommend making the gravel base 2’ wider and 2’ longer than the size of the shed. That way you’ll have an extra foot of space on both sides and ends to help prevent dirt from splashing up on the sidewalls of the shed.
How much gravel do I need for my shed foundation?
I recommend a 4″ to 6″ gravel base. If I had a choice, I would go with the 6″ deep gravel pad for better drainage and protection for your shed.
What type of gravel is the best for my shed foundation?
I usually recommend 3/4″ stone, which is also called 57 Granite. Another option is “crusher run,” which is a mix of 3/4″ stone and smaller stones.
Which type of gravel you should use depends partly on whether or not your shed will be located in a wet area. If the ground has moisture, you should consider using 3/4″ bluestone as it will provide additional drainage benefits over the crusher run.
One advantage of the crusher run is that it tends to become really compact after a while, and it kind of turns into “concrete,” so to speak. But if the area holds water, then that advantage turns into a disadvantage.
In most cases the crusher run will be slightly less money. If your shed will be resting in a dry location, this will work fine. If moisture isn’t a factor, it comes down to your personal preference.
Should I dig out the area before I put down gravel?
A recessed pad is optional unless you need to dig out a corner to level the ground.
If you prefer not to do any digging, you could use 6″x6″ wooden beams to build a frame around the perimeter of the shed foundation before you put 6″ of gravel down.
It is important to think about which foundation will work best for your property before you buy a shed online. Then, after your order is complete, you should prepare the right foundation for your shed.
Does the shed foundation need to be level?
Yes. The foundation needs to be level for the doors to open and shut properly. An uneven foundation will cause the shed doors to stick at the top or bottom of the door frame. You should use a bubble string level or a transit level to check the foundation. Make sure it is level from front to back, side to side, and corner to corner.
This is probably the most overlooked issue when it comes to garden shed foundation planning. Many people will just look the gravel foundation over with their eye and think it looks pretty level, without checking it with a tool. There are a few people who are really blessed with an eye for that kind of stuff, but most of us will run into trouble if we don’t use a level to make sure the foundation is level.
Do I really need a foundation for a shed? Can I put the shed on blocks instead?
I don’t recommend putting your storage shed on blocks. A gravel foundation is a much better option than blocks. If you use blocks, this can lead to settling issues in the future. Blocks also do not provide support for the full length of the structure.
If you are ordering a metal shed from Alan’s Factory Outlet, we can’t put it on blocks. Here are some of your options.
- Level gravel pad
- Concrete or asphalt pad
- On the ground
Please keep in mind some states and counties may require a concrete pad with footers so it is always a great idea to check with your local building department.
Choose the Best Foundation for Your Shed
Just like a house or a garage, the most important thing for a storage shed is to make sure it is built on a strong foundation. If you’re ordering a custom metal shed from Alan’s Factory Outlet, the base for the shed should be set up before the delivery.
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