A shed on your property is an ideal way to expand your storage space. Struggling to squeeze tools and equipment into a garage or basement can be a real hassle, and if you are a DIY type, sheds are simple to build and even easier to buy.
But selecting your new shed’s foundation is equally important as the design and build of your shed itself.
If the shed’s foundation is proper, your shed will sit level and sturdy for decades on an ideal foundation that stands up to the weather, water, and sinking. If you choose wrong, your shed won’t be worth the investment as it grows mold, rots, tilts, sinks, twists, and eventually fails or even collapses.
What Is The Best Shed Foundation?
Our best shed foundation recommendation is a gravel pad that is made out of crushed stone for most shed installations. A gravel pad shed foundation is our recommendation because they provide a stable base for your shed to rest on, are very effective at draining water away from the bottom of your shed as well as being affordable.
Below we discuss gravel pad shed foundations in more detail.
In fact, we go over all 13 shed foundation options for you to choose from so you can install which one you feel will work best for your use case.
1. Gravel Pad (Crushed Stone)
A gravel pad shed foundation is the best solution for most shed builders. As the top all-around option, a gravel pad for your shed is relatively inexpensive, scalable to any size project, and appropriate for almost any yard.
Typically, the material you’ll use is crushed limestone, not gravel. The process starts by clearing and leveling the site, then digging out the ground a few inches deep to match the footprint of your shed. You can go deeper to improve drainage and add a wood frame to reinforce the pad and add stability.
If you’re working in a sloped area, consider that building a wood frame dug out or built-up area with a level top can easily create a flat spot for your shed to sit. You’ll also be able to ensure that the doors are flush with the ground.
After your crushed stone or gravel is in place, use a gas-powered compactor to compress the material further. You can run the compactor machine more than once to create a very firm base, building up the material in layers. It adds to the expense, but the compactor’s work will pay off in terms of durability.
Finally, you have a level, compact, and sturdy pad. It will support heavy materials and equipment, and you can use this type of shed foundation for any size project.
You can handle building a simple gravel shed foundation if you have any DIY abilities. Moving crushed stone isn’t easy work, but a wheelbarrow, shovel, rake, and helper can make a large mound of material move around a work site quite easily. Plus, gravel is easy to buy, and a truck can usually deliver it reasonably close to your work site.
Overall, a gravel pad for your shed foundation is one of the most straightforward techniques for a shed project’s foundation.
Gravel is a relatively economical material. A whole truckload might only cost a few hundred dollars. The deeper you go, the more gravel you need. But, the thickness of your foundation will help determine its durability. Consider that going to a six- or eight-inch thickness doesn’t cost much more labor or material than a four-inch pad.
Renting a compactor will also add to your expenses by a few dollars but will pay off in the long run. If you add in timber framing, you’ll need to factor in the price of lumber and galvanized spikes or carriage bolts to fasten the frame.
- Excellent drainage and easy to level
- Scalable to any size shed
- Suitable for sheds with or without a floor
- Adaptable to almost any layout
- Very inexpensive
- Framing may be necessary to hold gravel in place, especially on a slope
- Possibility of sinking over time
- If the shed sits flat on the gravel, it may promote rot in areas with high moisture
2. Concrete Blocks
Concrete blocks are another DIY shed foundation. They are easy to buy at a big box or other supply stores, relatively inexpensive, and reasonably durable. Make sure you purchase solid blocks, as they are much more substantial. You can choose rectangular or square, and the footprint of your shed will determine how many you need.
Instead of supporting the entire shed like a gravel pad, your concrete blocks will support the shed’s frame at each corner, in the middle of each span, and in the middle of the floor. You can add more blocks strategically to resist the warping of the floor, especially if you plan on storing heavy materials or equipment in your shed.
Your project should start with a small gravel pad for each block. Then, stack and level your blocks at each corner and build up to your desired height. Remember that every block should be level with each other, as one uneven layer can spoil your result. Keeping things square and level will pay off in the long term.
Use a straight piece of lumber if your level doesn’t reach across a long span. Set it between and on top of two distant blocks. Then set your leveling tool on top of the wood to check for the level of the blocks underneath.
There isn’t much hard labor involved in building a shed foundation from concrete blocks. But, you must work precisely to level and square your blocks. So, the complexity level increases compared to a simple gravel pad. If you need to build a frame to support your shed, the difficulty factor increases a bit more.
In general, this is an ideal technique for a beginner.
Concrete blocks are generally relatively inexpensive, and you won’t probably need too many. So, they are one of the most affordable options for a shed foundation.
- It can help improve airflow under the shed, resisting rot
- Suitable for large or small projects and mild slopes
- Installation is fast, straightforward, and not labor-intensive
- Blocks are available in a wide range of sizes
- Not suitable for slopes of more than about two feet
- The spans between blocks don’t have support, so the floor is prone to sagging and vibration
- May sink over time, especially in damp areas prone to settling
A post-and-beam shed foundation can be ideal for those who are handy with carpentry tools. If your skillset includes framing or deck-building skills, installing posts and framing a foundation of beams should be fairly elementary.
You’ll need a minimum of four posts, one at each corner of a small shed. Larger sheds will need more posts, supporting the lengthier spans evenly. The post themselves can sit on gravel pads, be driven into the ground, or even be set as footers in concrete. The level of robustness is up to you, but concrete footers are the best choice in areas with harsh winters and frost heaves.
Then, you’ll frame out a series of beams that span the length of the shed and trusses that support the floor. If you can make a wall, deck, or roof frame from lumber, this process will seem quite familiar. Remember that you’ll want to use upgraded fasteners and screws that can handle additional loads if you’re going to use your shed to store heavy items.
Framing a series of beams isn’t easy if you’ve never done it before. Framing beams is a moderately complex task for the average DIYer, but one you might be able to handle if you have the skill and patience. Mistakes can drive up the cost of materials, and if you fail to build a level and square foundation, you’ll have to start over. Of course, you can always hire a pro if needed.
A post-and-beam shed foundation using lumber will probably be cheaper than pouring a concrete slab, even if it’s fairly large. But it will also probably be more expensive and time-consuming than a gravel foundation. In addition, if you have to hire a contractor, the cost will increase significantly.
- Relatively inexpensive materials are easy to find
- Ideal for sloped locations
- Setting posts in concrete makes for a very durable build
- Can help improve airflow under the shed
- Raises the floor above ground level, making it harder to wheel things in and out
- Could void the warranty of some pre-fabricated sheds designed to sit on gravel
- Won’t work with a floorless shed unless you build a floor
- Requires carpentry skills and tools
4. Concrete Piers
Concrete piers can work independently or as part of other shed foundations. They can be part of a post-and-beam project, supporting the frame. Or, they might sit flush with a gravel pad and lend extra support to the corners of your shed.
Concrete piers, or footers, are cylindrical. As you might suspect, they are solid, resistant to frost damage, and unlikely to rot. They even help satisfy strict building codes that you should consider, depending on where you live. You can buy pre-made tubes, set them in the ground, and fill them with concrete.
There are also some concrete tube products that are designed to help you level them on a slope, making them a good choice for uneven ground.
If you plan in advance, you might also be able to add mounting hardware for your shed right into the wet concrete so that it is a permanent part of the foundation when the mix has cured. This foundation technique is a highly sturdy option.
Mixing concrete is messy and can be labor-intensive. You must also create a concrete mix with the proportions correct for your application and allow it to cure correctly. That takes some skill and know-how, as well as adherence to the directions on the bag.
This sort of foundation is a moderately complex option for a shed, but it’s not overly complicated or too difficult for a DIY project.
Concrete tubes aren’t expensive, but it may take quite a bit of concrete to fill them. But, it uses much less concrete than a full slab foundation, so this is a reasonably inexpensive option.
- Ideal for sloped locations
- Very resistant to heaving and won’t rot
- Will likely satisfy even strict building codes
- Less expensive than full concrete options, but still durable
- Labor intensive and mixing concrete is messy
- More expensive and complicated than a simple gravel pad
- It doesn’t support the entire bottom of your shed, only where it sits on the piers
5. Concrete Slab (Floating)
Concrete slabs work as a sled foundation in areas that don’t see harsh winters. Typically, regions that see frost require a ‘weather-proof’ foundation, and a floating concrete slab doesn’t usually meet that code.
A floating concrete slab has no footers. It sits directly on the ground, so it’s less than ideal in areas with ice heaving and snow. It also has two significant disadvantages.
First, the drainage on a concrete slab is inferior, as water will sit and pool on the surface. That can end up causing rot, mold, and decreased durability of your shed. You could mitigate this by pitching the foundation and adding drains, which adds to the difficulty.
The second disadvantage is that concrete is expensive. A floating concrete slab might cost four times more than a simple gravel pad. Plus, building a concrete slab takes quite a bit of skill, as you must frame it with wood before pouring it, and you must also level it perfectly before it cures.
A floating concrete slab isn’t exceptionally difficult to make, but it takes some skill and experience working with concrete.
Another option is to buy a pre-made slab, but they tend to be too small for a shed and are more suitable for small equipment like generators or air conditioners.
Floating concrete slabs are among the most expensive options for a shed foundation.
- Extremely durable
- Provides exceptional support to the entirety of the shed
- Easy to mount and anchor your shed on top
- It can work well on slopes
- Building on a hill can double the cost
- Poor drainage
- Very labor-intensive
Pavers are simple, pre-cast blocks of concrete. They are ideal for smaller sheds, are easy to work with, and are very affordable. They are found in walkways, paths, patios, and pool decks and also serve as a practical shed foundation.
Typically, you’ll use sand or stone dust to create a level layer slightly below grade. You can compact the substrate by hand or with a machine. Then, once the surface is perfectly level, you can lay down your pavers.
It may seem like overkill, but it makes sense to lay the blocks in a pattern that helps lock them together. Therefore, rectangular blocks are a marginally better choice than square.
However, you don’t need to put down a base of sand or dust if you don’t want to. Just be prepared that they won’t remain level as long.
One tip to keep in mind is that you might want to have the blocks slightly below grade when you’re done, leaving a relief for the height of the entrance and floor of the shed. This way, you will have a perfectly graded and level entryway rather than a bump up into the shed.
Concrete pavers are extremely easy to work with, and even with a sand or stone dust layer, this is a fairly simple shed foundation.
Pavers are inexpensive, and so is sand and stone dust. You might be able to build the entire shed foundation for only a few hundred dollars or even less.
- Easy to work with
- Less messy than concrete
- Pavers are available in a range of sizes, colors, and shapes
- Ideal for working on flat ground
- Full support of the entire shed frame and floor
- Tough to install on slopes
- Pavers may settle and become uneven with each other
- Pavers can crack in frost heaves or under extreme weights
- Not a heavy-duty shed foundation
7. Plastic Grid (Permeable Pavers)
In the world of shed foundations, plastic grids or permeable pavers are relatively new. The hollow, rigid plastic material is usually partially made from recycled material, and you may find some entirely recycled products.
You’ll have to ensure that the ground you’re working on is flat, so you have to do a bit of digging to remove high spots. Then, fill any low areas with the extra dirt you have from digging.
If you want to go the extra mile or find imperfections, you can add a layer of sand to further level things and provide more of a base. Then, you can add garden cloth to help keep weeds from emerging under your building. Now, it’s time to lay out your grid sections.
The pieces are usually square, and they snap together to form larger and more extensive foundations. Make sure each grid is level and level to those you’ve already put in place. This way, everything will be level when you’re done.
The plastic pieces are pretty tough, but you can cut them down to size if you have any odd dimensions. Ideally, your permeable paver foundation will be either the same size or slightly larger than the footprint of your shed.
Now that you have your layout, fill the entire grid layout with pea gravel. This material will not only hold the plastic in place but also promote drainage under your shed, moving water away from the building materials.
This permeable grid is one of the most DIY-friendly shed foundation options.
Shed foundations made from plastic grids are among the most expensive. The high cost is due to the plastic grids themselves and the expense of the pea gravel.
- Very DIY-friendly
- Not labor intensive
- Plastic grid kits might be available for pre-fabricated sheds
- Easy to level
- Suitable for most shed sizes
- Not ideal for areas that see hard freezes
- It doesn’t work on slopes
- Sometimes hard to find in stores
- Relatively expensive
8. Deck Blocks
Deck blocks are trapezoidal, square on the bottom, and narrower on top. They sometimes have grooves cut in the top, making channels for you to lay wooden framing. These cut deck blocks are ideal for combining with post-and-beam framing.
Simpler deck blocks have a flat top. But, the principle is the same.
Each corner and every span of four to eight feet needs a block. Lay them out in a grid pattern with equal spacing, matching the footprint of your shed. If you have a pre-fabricated shed, it may have rigid sections or beams on the bottom that will help you match the design of your blocks to the shed.
Alternatively, you can create a timber frame to act as a subfloor for your shed, sitting between it and the tops of your blocks. The last option is to sit your shed flat on the blocks without any extra beams, frames, or support. That will only work with a shed that has a flat floor.
Make sure your blocks are level and level with each other. This sort of design is ideal for DIYers and requires little extra material or construction skills.
Deck blocks are a simple shed foundation that doesn’t require specialty tools. You can add framing if you have the skill to do so, but it’s not strictly necessary.
Deck blocks are not expensive and don’t require extra material to create a shed foundation.
- Easy to work with
- Available at most big box stores
- Scalable to your project
- Won’t bear heavy weights without additional framing
- Won’t work well on a slope
- Squarely setting the blocks can be a little tricky, enough so that you might want a helper and a straight edge
9. Screw Piles
Screw piles are a different take on shed foundations, similar to concrete footers. But, instead of digging to install them, you’ll screw them into place. Screw piles are another relatively new option for shed foundation installations.
When first introduced, screw piles became a mainstay in housing construction. They can be expensive, and they may require specialized equipment to install. The piles have a screw or helix-shaped bottom. Big companies with heavy equipment may install them with an attachment on a construction vehicle, screwing each pile into the ground.
In homeowner-scale projects, you can install them with a bar that helps you torque them into the ground. This installation requires strength and determination, as it can be hard to gain the necessary leverage to do so, even if you use the leverage tool that might come with the screws.
The advantage over digging a post hole and placing a footing is that screw piles don’t disturb the ground as much as a shovel. So, there is less risk of settling. When you drive them far enough into the ground, they are frost-proof, adding to their popularity. And, since each pile can be adjusted individually, screw piles are ideal on uneven or sloped surfaces.
Once set, mount a bracket on the top of each screw pile. Then you’ll install a frame to hold the weight of your shed, similar to other installations. There are different brackets and attachments that you may affix to the top of the screws, making this a fairly flexible option.
Screw piles don’t take specialized skills. But installing them into any rocky ground will probably require heavy machinery. They’re much easier to use in looser soils. Though the installation is pretty straightforward, you’ll need skills to set your attachments and build a frame, if necessary. So, this is a moderately complex installation.
Screw piles aren’t as expensive as concrete, but renting heavy machinery is a possible add-on cost. Plus, you’ll likely need to build a frame and buy proper attachments for your shed design.
This project ranges from relatively inexpensive to costly, depending on scale.
- Minimal risk of settling due to screwing action (no digging)
- No special skills needed to install
- Works well on slopes
- Installations can go quite quickly
- Manual installations can be hard work
- Machine installations can be expensive
- Screw piles and any additional materials can add up to high prices
- Still may need framing
10. Skid Foundation
A skid foundation isn’t a true foundation. Instead, it’s a simple structure that creates a base for a shed to rest on, integrated into the shed. It’s best to think of a skid foundation as a part of the shed’s structure rather than as a real foundation.
Most, if not all, pre-fabricated sheds come with a skid foundation. They help the shed stay secure during shipping and support the shed’s weight. For very simple, temporary shed installations, a skid foundation might be enough to support your structure.
However, without additional support, the shed may move, shift, or twist, as it doesn’t have a true base that connects it to the ground. So, many sheds with skid foundations sit on a gravel or concrete pad.
You could also build a simple skid foundation for a temporary structure. All you need is some lengths of timber laid on the ground. Then, cut notches for the runners or beams on the bottom of your shed to sit in, and the wood will support your shed.
Skid foundations are extremely simple and non-complex. They often come as part of a store-bought shed, offering some strength to the shed floor base.
Skid foundations are superlatively inexpensive. They might even come as part of your shed.
- Very inexpensive
- Part of many existing sheds found in stores
- Easy to build
- Usually requires the addition of a foundation
- Sitting in the dirt (rather than on a foundation) can promote rot
- Prone to settling
- Not technically a foundation
11. Metal Kit Foundation
Metal kit foundations are popular because they are easy to work with, relatively lightweight, and generally affordable. You might see them bundled with sheds found online and in budget stores. Typically, each metal kit is sold as an add-on option for a specific model of the shed.
A metal kit foundation has metal runners and beams that you piece together on-site. The resulting frame looks like a timber frame but often lacks the structural rigidity of wood. Because these are inexpensive kits, they tend to be a bit flimsy. The metal components can warp easily in shipping and over time, so they are only suitable for light-duty projects.
Unfortunately, metal kits also require a completely level location. So, you’re probably going to have to do some work to remove high and low spots before you can even set it in place. That might add some labor to your project, especially if you have any sort of slope to contend with.
If you go into the trouble of adding gravel, it might be better in the long run. That will give the metal kit a sturdy pad to rest on.
But gravel adds to the labor, complexity, and expense of your project. The typical shed you’ll find bundled with a metal kit foundation isn’t built to stand the test of time. So, your gravel pad may outlive the structure.
Metal kit shed foundations are very easy to work with and install. You will need to do a good job of leveling your site, but that’s not complicated.
Metal kit foundations are very affordable and may come as part of an inexpensive shed. Just remember that you often get what you pay for.
- Simple and easy to work with
- Don’t require special skills or tools
- Part of some shed kits
- Only an option for specific sheds, and must match the manufacturer’s specifications
- Not suitable for cold weather or sloped installations
- Generally not durable
- Some kits are very low quality
- Prone to settling
12. Metal Jacks
Metal shed jacks are another fairly new shed foundation innovation that is often easier than older techniques. Metal discs or squares sit directly on the ground, and integrated screws attach to hardware on the shed’s frame. They are very easy to work with, offer easy leveling, and don’t require special tools.
The installation of metal jacks is a little tricky to conceptualize, but once you get the idea, it’s very straightforward. First, you’ll flip your frame so that the bottom faces up. Next, attach hardware from the metal jacks at each corner and the midpoint of any long spans. This hardware has a hole for a long, thick screw.
These oversized, foot-long screws thread into the hardware. Then, you’ll thread the metal plate onto it. Then, flip the whole structure over again so it is standing on the screws. Go around the foundation with a hammer and block, tapping each screw into the ground. Repeat for each point on the frame.
Gradually, your screws will penetrate the earth. Tap each site a few times, then move to the next. Make your way around and around, alternating between locations so that your penetration is approximately equal. This approach will help the screws go in straight, keeping things square and getting your frame level, just off the ground.
Then, you can adjust the height of plates by spinning them down until they contact the earth. Adjusting the screws and plates allows you to level your foundation quickly, with no digging.
You can also set your foundation in place for a few days and let it settle. This settling time will give you a second opportunity to make any final adjustments to your screws and the overall level of the foundation.
Metal jacks are a straightforward installation that requires no special tools. It’s very DIY-friendly, but you’ll need to watch a video or study an installation guide to understand the finer points.
Metal jacks are a moderately priced shed foundation option. There isn’t any extra material to buy, but the metal jacks aren’t cheap.
- Simple, straightforward installation
- Quick adjustment for leveling minor slopes
- Metal is a durable material
- Not suitable for vast sheds or those with pre-fabricated bottoms
- Not a good option in areas with brutal winters
- Adjustments max out at around six inches with most kits
- Rust and corrosion can be an issue, so always look for high-quality components
13. Concrete Foundation w/ Footers
Sheds with a concrete foundation with footers are strong. This technique is the most durable, frost-proof, and heavy-duty option for a shed foundation. This type of foundation can be a monolithic pour or one with concrete blocks and footers.
A monolithic foundation has one large pad of concrete set on footers, and all the concrete is poured at once. This technique is best for situations where there is a limited slope, not to exceed about one foot across the whole project.
A concrete block foundation comes in three separate phases. First, large concrete footers go into the ground, usually to a frost depth that meets the area’s building code for frost-proofing.
Then, once the footers have had time to cure, short concrete block walls are laid on them, creating a raised perimeter. Last, a thick concrete pad is poured, forming the floor of your new shed.
The walls of the shed will sit on the perimeter block. This technique is a large-scale project and one that’s ideal for heavy-duty or large sheds. For example, if you’re building a two-story shed for your tractor, woodworking shop, and accessory apartment, this is ideal. But it’s overkill for a small utility shed that holds your lightweight gardening tools.
A concrete foundation, even one of monolithic construction, is pretty complex. There are materials to manage and multiple steps and considerations that only grow when you step up to a three-phase project with footers, blocks, and a pad.
Concrete foundations with blocks and a pad are expensive. But they are the most durable and resistant to the freeze-thaw cycle.
- Frost-proof construction
- Very durable, very strong
- Capable of supporting heavy structures
- Very high costs
- Specialty skills and hard labor are required
- Probably over-the-top for most shed designs
Frequently Asked Questions
Do I need a foundation for a shed?
You don’t explicitly need a foundation for a shed, but it will probably last much longer with one. Shed foundations all have different strengths and weaknesses, but they help stabilize and support your shed.
Can you put a shed directly on the ground?
A shed can rest directly on the ground but it is not recommended. Having your building in direct contact with the soil will not allow moisture to escape and can promote rot and deterioration.
What is the best base for under a shed?
The best base for under a shed is one matched to your needs. For example, a lightweight, simple shed might do just fine sitting directly on the ground. A medium-duty shed might need a gravel pad to keep it secure. A heavy-duty project might need a concrete pad or complete foundation.
What is the cheapest foundation for a shed?
The cheapest foundation for a shed is probably a kit. Many inexpensive sheds come with the option to purchase a metal kit that acts as a substitute for a true foundation.
Do I need a gap under my shed?
You don’t need to have a gap under your shed. But maintaining airflow under it can help keep things from getting too wet. This will limit the risk of mold or rot. Just make sure to seal up any gaps to keep area wildlife from moving in.
When you are building or installing a shed, you have to consider a few factors to decide which shed foundation is best. Cost is a significant consideration. You’ll also need to account for your skill level, the complexity of the build, and the need for any specialized tools and equipment.
Additionally, the terrain you’re building on and the climate in the area can also influence your decision. Areas that see hard freezes need more robust foundations than areas that don’t get hard winters. Plus, slopes and rocky terrain can make your build a bit more complicated.
It’s also a very smart idea to check your local building codes to make sure that your project will comply with the rules in your municipality. You don’t want to run afoul of building regulations and have to redo your hard work. That can be both expensive and upsetting.
Now that you know all there is about shed foundations, you can go and get your project started today!