A solid foundation determines the duration of any good thing in life. The same goes for sheds with solid foundations. Regardless of how strongly built your shed is, it won't last for many years without being attached to strong foundation or without proper ground preparation being made. The foundation of a shed gives strength to the walls, and supports the shed's roof, which is the most important part of a shed.
You may be wondering why you even need to build a shed, but having a shed serves as an extra space. Getting a shed will help you manage your space and create a storage apartment to safely keep your tools, Christmas decorations, electronics, or any load you can't bear to walk away with yet. However, shed bases are the most important in the construction of sheds, and you need to put in all your efforts.
Why Proper Shed Foundation Is Important?
As we said earlier, having the best shed foundation will ensure how durable your shed will turn out to be.
Without a strong foundation for shed, it won't last during the rainy season because water will get into it and cause rusting of the metals; hence you can't put your shed directly on the floor. Also, there's the problem of stability too. Building a shed without foundation can affect its balance because of the uneven ground, which can cause the door of the shed not to open up fully.
Sheds must be placed on a concrete shed base with a level surface so it can remain intact. However, you need to remember to lift it slightly off the floor to ensure proper water drainage and prevent ground moisture.
Can You Build a Shed Without a Foundation?
The answer to this is dependent on the size of your shed. You can get away without a shed foundation if you want to install a small shed. But if your shed is bigger than 8 by 8, or even 6 by 8, then it needs attaching to a foundation.
One of the major benefits of a shed foundation is to protect the shed and extend its usability. The truth is, a shed foundation is important for smaller sheds as well.
If the total weight of your shed is above 400lbs, you need to install a foundation for it. The installation of a shed isn't just because of the weight, but you need to consider the things you'll be storing in the shed as well. If you are installing a shed that comes with a built-in floor, you might not need to build a foundation.
Lastly, before building any foundation for your shed, you might need to consult your local building inspector. There might be some local regulations concerning shed installation you don't know about.
What Are The Different Types of Shed Bases and Foundations?
Different foundation types are grouped into two main categories; on-grade foundation and permanent shed foundation (frost-proof foundation).
On-grade foundations rest on flat ground and are built with treated gravel pad, plastic base, or solid concrete blocks that can be removed whenever you move out; it could be in 15 years; yes, it'll last that long. Because it's not a permanent shed foundation, because it can be moved at any time.
Permanent shed foundations, as the name implies, are permanent foundations and they are stronger and more durable than the on-grade types. They are perfect for colder areas that experience frosts.
You can make frost-proof foundations by pouring concrete footings or concrete slabs. Alternatively, you can build one by putting tall round poles into deep holes. Permanent shed foundations are perfect for larger sheds.
On-Grade Foundations
Shed Foundation with Concrete Pavers
This type of shed foundation is very easy and a great option for beginners, but it can only be installed if your land level is flat because you need a good base to make this work. To anchor the shed, you need to use concrete slabs, but there's a tendency to be affected by heavy wind, so it's best to use heavy pavers. With pavers, your shed is on a level platform with the ground making it perfect for riding quads. For proper water drainage, dig out 2 inches of dirt from the ground and fill it with gravel.
Difficulty Level: It's very easy to lay this type of foundation, especially when working on a flat and level base.
Durability: A well-made concrete foundation can last for decades without any issues.
Waterproof: Yes, if you position a sealant between the shed's frame and the concrete floor.
Cost per square meter: $45-$60 for concrete pavers.
Solid Concrete Blocks
Solid concrete blocks are easy to build and more flexible than sheds with concrete pavers but not so durable. To efficiently make this foundation type, pile up the concrete blocks on the shed floor, and ensure the slope is small, so it's suitable and stable enough to withstand pressure from low winds. Building a shed foundation with a concrete block requires digging out 6 inches of dirt from each block stack and padding it using gravel. Create a wood foundation that will connect to the block and serve as a frame the shed sits on. There is no need using floor joists for sheds that come with floor frames, but if yours doesn't, simply place plywood on the floor and freestyle with any flooring type you desire. The amazing part about this type of foundation is that you can build it to whatever shed size you want; how many blocks you'll need depends on you.
Difficulty Level: Easy
Durability: It can last up to 5 years with proper maintenance.
Waterproof: No
Cost per square meter: $30-$100, but the price can vary depending on size and thickness
Deck Blocks
Deck blocks are made from concrete and can comfortably hold 2 by 6 joists or 4 by 4 posts. It's pretty easy to make too, and very similar in construction to the shed with concrete blocks. This is perfect if you install it in a water area because it's specifically designed to keep your shed from sinking. The deck blocks give it a push above ground contact, and it's more stable because of the presence of a fitted channel to support the pressure-treated lumber. However, you can't use it if you intend to store heavy equipment because it'll affect the structural integrity of the shed.
Difficulty: Easy, because the focus is on just on leveling the blocks.
Durability: It can sink over time. Probably 5 years
Waterproof: No
Cost per square meter: $50-$75
Crushed Stone and Timber Frame
If your shed has a built-in floor, the timber frame foundation is just what you need. Because the foundation is made of straight timbers, it can serve as an excellent level of support. The crushed stone that makes up the timber foundation allows water to pass through rather than soaking the shed's site. Also, use pressure-treated lumber for the timbers, so it doesn't rot.
Difficulty: Relatively easy
Durability: 10 years if done properly
Waterproof: No
Cost per square meter: $45 to $60
Plastic Foundations
Plastic grid systems are perfect for flat ground. It's beginner-friendly, cheap, and easy to install. Just level any high surface/slopes, and pour pea gravel on the open grid.
Difficulty: Relatively easy, as the only difficult task is arranging the grids uniformly.
Durability: 5 to 10 years
Waterproof: No
Cost per square meter: $100 to $300
Skid Foundations
Skid foundation involves putting the shed floor joists on pressure-treated runners. However, never place it directly on the floor; you can dig holes, and the holes dug should be filled with gravel to keep the shed dry.
Difficulty: Easy
Durability: 5 years
Waterproof: No
Cost per square meter: $50 to $100
Wooden Floor On Gravel Base
Building your shed floor on a gravel base is a common process because it doesn't involve a lot of money. It's budget-friendly and a better option than building your shed directly on the sand. However, it's not the best choice for areas with high wind; the best place to use this is for warm environments.
Difficulty: Easy
Durability: 2 to 5 years if properly built
Waterproof: No
Cost per square meter: $70 to $100
Permanent Shed Foundation & Bases
Poured-Concrete Slab
A concrete slab is the best foundation for sheds intended to support more weight. You can create a concrete base with a slab by simultaneously pouring the perimeter foundation walls and shed floors. The wall, which is commonly thick, will spread to the frost line, while the floor will be supported using a wire mesh. If after you pour concrete, and it looks like it wants to rain, cover the surface with plastic, and wait until the concrete hardens.
Difficulty: Difficult, and you may need a professional to execute this perfectly.
Durability: Permanent if done well
Waterproof: Yes
Cost per square meter: $75 to $110
Concrete Piers and Beams
A concrete pier is ideal for large sheds cons, but constructing it can be difficult in most cases. The piers are then concrete poured into the already drilled ground. If you usually have freezing temperatures or experience frost regularly, make sure the holes go way beyond the frost line to prevent easy access to frost heave.
Difficulty: Difficult and requires professional expertise
Durability: Permanent if constructed well
Waterproof: Yes
Cost per square meter: $150 to $400
Post and Beams
Construction of this type of shed is similar to the concrete pier but more complicated. It's a very popular method and perfect for anyone who already has carpentry skills. You can support post and beam foundations sheds on posts with concrete footers, as this is perfect for any location prone to winter frost. However, this type of shed is not recommended if you plan on using your shed as a garage to store heavy equipment.
Difficulty: A bit difficult because you need to make sure that the horizontal and vertical posts align
Durability: 10 years
Waterproof: Yes
Cost per square meter: $200 to $500
Pole-Barn
A pole barn is different from the other types of sheds we have listed in this article because it doesn't even come with a floor. To construct a pole barn, you need to dig holes around the foundation's perimeter. Place the concrete pad on the already dug hole, and adjust your pressure-treated lumber into the hole. You can basically make use of bulk materials to fill the hole, and these materials will serve as a helpful means to drain water out of the lumber.
Difficulty: Difficult because it requires heavy work, so you need the help of a professional to do it right.
Durability: Permanent if done properly
Waterproof: Yes
Cost per square meter: $100 to $300
Screw Piles
Generally, the concept of building a shed foundation with the screw piles method is simple. You use big metal screws/bolt to push the piles deep into the ground, connect brackets to the top, while linking the shed skids to the brackets. However, in some cases, you might need a small excavation tool to screw the piles into the ground. Screw piles are classified as frost-proof foundations, and they can be set at different heights to raise the building.
Difficulty: Simple
Durability: Permanent if you use quality professional services
Waterproof: Yes
Cost per square meter: $400 to $700
Can I Use Cinder Blocks For a Shed Foundation?
If you decide to build a shed to store items you no longer use, or as a site for woodworking and fixing cars, you need to ensure the foundation isn't faulty. Cinder blocks are used for shed styles that don't require too much pressure, but if you are looking to build a large shed on your lawn/grass, putting cinder blocks beneath isn't the best option. When exposed to water, cinder block will get damp and crack/decay leaving your shed quality compromised.
How To Choose The Right Foundation For Your Shed?
Landscaping the exact corner where you'll erect your shed is the most important. You need to compact the dirt and use blocks to create a leveled layer.
The next step is to use a concrete pad in creating a level surface. The levelness of your concrete will determine the minimum and maximum life span of your shed.
If you are using an already-made shed, it's important to follow the manufacturer's instructions, so you know exactly what to do.
How Deep Should Foundations Be For A Shed?
If you are dealing with large structures, the footing should be extended 14 inches below the frost line. How deep your foundation will be is determined by the size of your shed.
Medium sheds can be 12 inches below the frost line. And for small sheds, a gravel pad of 4 inches will suffice.
How Do I Prepare The Ground For A Shed Base?
When you have decided to build a shed, keep in mind that the shed foundation shouldn't be on low-lying grounds to avoid it being covered by water in case of a flood. Ensure that the ground is in a leveled shape to save it from collapsing in the long run. It's better to set things right at the beginning than have regrets later. Also, let there be enough distance around your shed base, so you don't have to worry about weeds spreading around the edges of the shed.
What Dimensions Should A Shed Foundation Be Compared To The Shed?
If your shed foundation is without a floor frame, the concrete pad must be the same size as the wall's width of your shed. But, if it has a shed floor, let the gravel foundation dimension measure two ft longer in terms of width and length than the wall dimension.
Conclusion
Your decision on shed foundations is a matter of importance because that's what determines the life span of your shed. To avoid cracks, do not construct your shed foundation at the edge of trees because it gives it enough room to grow and attach itself to your shed. All shed foundations have their pros and cons, so select the correct one based on your preference and additional factors you might want ( electricity or running water).
Interested in available options, ideas and materials for other parts of your shed?
Check our dedicated guides on:
FAQs
1. CAN YOU PUT A SHED FOUNDATION ON THE GROUND?
Placing your shed foundation on the ground/soil is a bad idea, as it can cause moisture to seep into the shed directly, and rot might begin to form.
2. WHAT IS THE CHEAPEST WAY TO BUILD A SHED FOUNDATION?
3. WHAT IS THE BEST MATERIAL TO USE FOR A SHED FOUNDATION?
4. WHAT IS THE MINIMUM THICKNESS OF A SHED FOUNDATION?
5. DOES A SHED NEED FOOTINGS?