One of the most affordable ways to add storage to your home is to build your own shed.  

We built ours from the ground up and it has surpassed our expectations! 

This is not a pre-fabricated, flimsy, one-size-fits-all shed. You can create exactly the kind of storage you need for your belongings, in the space that you have available. And it will last a very long time.

This post will show you how to build the shed floor. 

Have a look at what we’ve done so far:

Steps before building a shed floor

1. You need a shed plan. In another post, I share how to create a shed plan, which will help you build the shed floor in this post. 
2. Before you can build any part of the shed, you need to establish a foundation. For our shed build, we decided on and installed a paver foundation for the shed. In addition to the pavers, we added gravel around the area to keep grass away and help with water draining off the shed roof.

Please remember that we are not professionals and we cannot be responsible for the outcome of your project.

Should I use 2×4 or 2×6 for the shed floor?

Now that you have decided to build a shed, you need to determine the size of the lumber you will use for your shed floor: 2×4, 2×6, or even 2×8? Which is best?

To help you choose the right materials, consider how you will use the shed and what types of items you plan to store. Will you have a large number of heavy items in your shed?

If you plan on storing light-weight items, I would recommend using 2×6 treated lumber for your floor. 

If you plan on storing heavy items, such as large equipment, you will want to think about using 2×8 treated lumber for the floor but you can still use 2×6 lumber if you add more bracing to support the weight.

Can you build a shed floor with 2×4?

After answering these questions, you might wonder, can you still build a shed floor with 2×4’s? 

Yes, you can! 

If you plan on building a small shed with no intentions of heavy storage, you can use 2×4. 

SIDE NOTE: An example of items to store in this small shed would be shovels and rakes – this type of shed would be more of a garden shed. 

If you want to store heavy items (like a push lawn mower), you can still use 2×4 for the floor but you will have to place the 2×4’s closer together to get you adequate support needed. It would be a good idea to add blocking as well. 

SIDE NOTE: To find out what blocking is in construction, Wikipedia shares the basics of what blocking is in framing.

But, at this point, with the extra wood needed to support the floor, you would be better off using 2×6 lumber. 

If you’re still questioning what size of lumber to use, the most commonly used option to construct a shed floor joist is a 2×6. That’s why this tutorial shows you how to build a shed floor with 2×6 lumber. 

How do I keep my shed from rotting? 

The first step to prevent your shed from rotting is to raise the shed off the ground and onto a strong, stable foundation. If you have been following along with the building of our shed, you will know that we placed our shed on a paver foundation. 

The second step is to use treated lumber for the flooring. 

If you are not completely sure what treated lumber is, Home Depot has a great article called “Types of Pressure Treated Wood”.

What type of plywood should I use?

We have talked about the framing material but what about the plywood that sits on top of the framing, the subfloor?

The thickness of the plywood will depend on what you plan on storing in the shed. If you will not have heavy items stored in the shed, you can use 1/2” but for heavier items, you will want 3/4”.

It’s also a great idea to use plywood that is pressure-treated or made for exterior use.

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Step 2: Square the floor framing

Now it’s time to square the floor framing. To do this, measure in an “X”, one corner to the opposite corner. Then, see if the two other corners equal the measurement. If they have different measurements, adjust the framing and repeat until you finally have the same measurements.

Step 3: Add the plywood to the frame

After the floor framing is square, it’s time to add the 0.75″ plywood. 

SIDE NOTE: This can be regular plywood or grooved plywood. 

But whatever you do, the edges of the plywood need to be on a framing board in order for it to be properly secured. If two shorter plywood pieces need to be placed on the same framing board, have the plywood piece sit halfway across the board. This way, both boards can be attached to the board. 

The easiest way to cut the plywood is to use a Kreg Rip-Cut or a scrap board with clamps. We used the Rip-Cut the most – see how to use it yourself!

Once the plywood piece is the right size, apply subfloor adhesive (liquid nails) to the floor framing (only where the plywood will sit). Then, set the plywood in place and secure with 2″ nails or screws.

TIP: Make sure you are nailing where the framing is – a chalk line will help with this.

Now, measure, cut, and place the remaining plywood pieces until the floor is completely attached.

SIDE NOTE: This is very similar to the process of the flooring when building a house, but in the case of a house, would use grooved plywood and would make sure your cuts/seams of the plywood are staggered for support reasons.

Once the final piece of plywood is secured, your floor is now complete!

Now that your shed floor is built you are ready to build the walls for the shed.

How to build a shed floor

Yield: shed floor

Prep Time: 30 minutes

Active Time: 3 hours

Additional Time: 10 minutes

Total Time: 3 hours 40 minutes

Difficulty: Moderate

Estimated Cost: $$$

Building your own shed can be intimidating but don’t let it. With this tutorial, you will build a strong shed floor that will last for years and years.

Print

Materials

• treated lumber (we used 2″ x 6″)
• 3/4″ plywood (subfloor)
• 3″ exterior screws
• 1.5″ exterior screws
• liquid nails for subfloor

Tools

• miter saw
• circular saw
• tape measure
• pencil
• clamps (optional)
• chalk line
• drill
• Rip-Cut (optional)
• safety glasses
• face mask (for dust)
• ear protection

Instructions

1. Cut the treated lumber to the size of the shed, use a plan.
2. Square the floor framing.
3. Add the plywood to the frame.

Notes

Make sure you have created a Shed plan, I share a printable to makes this easier.

Plus have your shed foundation in place before building the shed floor.

Next step: Build the walls for the shed