So you want to build a potting shed? You’ve come to the right place. Your options are to build it according to my dimensions — an 8’x10’ base, with walls that go up to 8’ where sits a gable roof pitched to a 45° angle. You can also customize this to your own preferred dimensions, and I’ve tried to notate variations that can be made to do so when possible. Keep scrolling!

Consider Your Intended Use & Choose the Best Spot

This may seem like too obvious a step to even include, but ideally, you want a flat and level part of your backyard that gets at least six hours of sunlight a day if you intend to use it as a greenhouse. A shadier spot works if you plan on mostly using it for working in and tool storage. We took the extra step of hiring a landscaper to lay an 8’x10’ concrete slab and running electrical wiring to it so we could easily plug in string lights, fans, etc. This is an entirely unnecessary step for something as simple as a potting shed, and many other DIY guides and professional builders will construct a shed right on the plain ol’ ground. Ultimately, we went for a shadier option, as New Orleans is already so hot for much of the year. We figured we would extend the number of days we could use this space by having ample shade.

Gather Window & Door Measurements and Make Your Plans (figure 1)

Before you can actually begin the build, you want to have collected all of the windows and doors you’ll be using so that you can accurately make plans for the structure. If you’re using windows and doors from a salvage store like we did (cost effective and sustainable!), you’re going to base your framing dimensions off of the windows and doors you find, not vice versa. If you plan to be purchasing new windows and doors for this, you have a bit more freedom in deciding exactly how you’d like it all to be laid out. We sketched out what our ideal potting shed would look like, headed to the salvage yard, and tried to find windows and doors that fit closest to that vision. Then we used those items to make our framing measurements.

Erect your corner posts (figure 2)

Once you’ve got your framing plans made, erect four 8’ long 4’x4’ corner posts, which will act as the primary support for your structure. We recommend having a helper for this part, as the posts can be heavy and awkward to maneuver on your own.

Now, depending on how permanently you’d like to install this potting shed, you can go about erecting the posts in one of three ways:

Option 1: For a Non-Permanent / Moveable Structure | When we say movable, we’re talking a 10-person lift team, so, keep that in mind. Create a “base” rectangle of 2x4s that fit your desired dimensions — for us, that was two 8’ long and two 10’ long 2x4s — that will lie flat on the ground and be used to attach the 4x4 corner posts (which you will then screw into the base 2x4s).
Option 2: For a Structure Built On A Concrete Foundation (like we did!) | Do just as above and create a “base” square of 2x4s that will lie flat on the slab foundation. Using screws that can be driven into concrete and a hammer drill, attach the base square to the concrete slab and erect the posts in the four corners of the square, screwing them into your base 2x4s.
Option 3: For a Permanent Structure Not On A Foundation | Dig holes in your four corners to a depth of at least two feet. Note that this means the posts you purchase for this method must be at least two feet longer than your intended final height of 8’. You can use a post hole digger or an auger to make the holes. Make sure the holes are correctly spaced and level, and double check your measurements to ensure the posts will be the correct height. Next, stand your corner posts up in their holes and use a level to make sure they are straight and plumb. You may need to add or remove soil from the holes to get the posts level. Once the posts are in place, fill the holes with concrete, and let it dry according to the manufacturer's instructions.

***Figure 2 | Notice that the 2x4s are laid flat against the foundation where they’ve been screwed into the concrete with masonry screws. The 4x4s are then screwed into the 2x4s at each corner.***

Secure beams atop Corner posts (figure 3)

Now that your corner posts are securely in place at the base, it's time to secure them up top. I staggered two layers of 2x4 boards screwed downwards into each other and to the corner posts (reference the top right corner in figure 3 below) or take a look at figure 3.1 for the staggering pattern I used, as viewed from above. This pattern helps distribute the weight of the roof in all directions, as opposed to shortening the long side and lengthening the short side or vice versa. Please note the small gaps in figure 3.1 are just for viewing simplicity. In your project, the boards should meet.

To attach the beams, first cut the eight 2x4s to the correct length using a circular saw or miter saw. Place the first four 2x4s on top of the corner posts according to the pattern of the lighter outline in figure 3.1, making sure they are flush with the edges and evenly spaced. Then, use metal brackets or wood screws to secure the beams to the posts. Repeat this with the next four 2x4 beams on top according to the pattern of the darker rectangles in figure 3.1.

*Figure 3.1* | configuration of the top 2x4’s as seen from above.

Insert Windows into Walls (figure 4)

Here’s our favorite part, and the step that’s most responsible for the look of this thing: we’re using mismatched sets of old windows that we either saved from our own house when we updated the windows last year or salvaged from various local stores around town. Some of our favorite places in New Orleans to shop for old stuff like this are Ricca’s, The Bank Architectural Antiques, and The Green Project.

The best thing about this project is the windows do not need to be installed like typical functional windows would, because we don’t really need them to open. Trust me when I say that would make this DIY a lot less intermediate-friendly. Or maybe I just suck at normal window installation.

Find windows similar in size, but don't just slap any old window in there — choose ones that match the style of your shed and let in the perfect amount of light. And make sure to seal them properly so you don't get any unwanted critters sneaking in. You won’t want to be sharing your potting space with a family of raccoons.

Erect temporary supports for The ridge beam of the roof (figure 5)

The rafters need to connect to your ridge beam, which is the board at the center and topmost point of the roof. But you can’t just start with the rafters — the ridge beam needs to be in place first so there’s something for them to connect to. But if the rafters are what holds the ridge beam up, how do you do that?

Temporary support! Attach two 2x4s to the front and back beams, dead center, and pointing up vertically, as seen in figure 5 and figure 5.1 below. Then measure to find where the rafters will ideally meet the ridge beam and mark it at the same height — 4’ —on both sides. Attach the 2x6 ridge beam to both boards and voila, you’ve erected yourself a ridge beam. This is bound to fall apart if you just leave it like this, so please continue to the next step.

A note for anyone customizing their dimensions: the height I placed the ridge beam was determined by dividing the width of the entire structure in half, which is the same as the distance from the center of the front wall all the way to the left or right side of it. Basically, just make sure that if your structure is 8’ wide, you place your ridge beam 4’ higher than the wall header. If you’re making your shed less wide than that, say 6’, you place your ridge beam 3’ higher than the wall header. If you’re making it more wide than that you may want to consider finding alternate resources for framing out your roof, because the style of roof we’re making here (a gable roof with a 45° angle a.k.a. a 12/12 pitch) will start to add far too much height to your entire structure as the width increases.

Attach Rafters Between Walls and Ridge Beam (figure 6)

Now that you have a sturdy and well-supported ridge beam as your roof’s backbone, it's time to add the ribs of your roof — the rafters. The rafters hold it all together and give the roof that nice sloping angle to protect your shed from the elements. It's like a really stylish hat for your potting shed, keeping it cool in the summer and dry in the winter.

You'll want to make sure they're level and secure, so take your time and use the proper hardware: rafter brackets, power drill or driver (two trusted options at different price points: Black and Decker; DeWalt), and look, a good tool belt gets a lot of use if you’re finding yourself diving into DIY world. This is another place where having a trusty helper comes in handy, someone who can pass you tools and offer moral support while you precariously balance on a ladder. We found that using rafter brackets was a simple and easy way of attaching the rafters to both the ridge beam and to the beams sitting atop your corner posts. You’ll want to place one set of rafters every two feet of your roof so that your roof material has enough support. For a roof that’s 10’ deep you will need six sets of rafters cut to 6’ with a 45° angle that can meet the ridge beam flat. See below for an illustration of how the rafter meets the ridge beam.

Below in figure 6.1, check out how I cut our rafters on left, vs figure 6.2, another way you could leave the rafters if you’re fine with the look and want to save yourself half the cuts.

See figure 6.3 and 6.4 below for what the rafter attachment process looks like.

Install Doors (figure 7)

We waited until the rafters were done to install doors because we needed to use our big ol’ ladder inside of the potting shed for the rafters and didn’t want to risk damaging the doors with the ladder. We chose French doors for this (in step 1) because we love the look, but if you want a more weatherproof door or one that you can more securely lock, a single door may be your best bet. We could write a whole blog post on door installation, but instead, we’ll just link you to a video that shows you how.

Install Siding for lower wall & all non-window walls (figure 8)

I decided since this would be an outdoor storage area that would see a lot of activity, I didn’t want the glass of the windows to go all the way to the ground, so we created a rough sill at about shin height that the windows can sit on top of. You’ll then add siding of your choice (we used cedar siding, but you can use metal sheeting, wood, or plastic sheeting) to the exterior of the shed starting at the sill and working your way down.

Fill in Gaps

Now that your shed is starting to take shape, it's time to fill in the gaps. This is equal parts vanity and function — it’ll look more solid but also help regulate temperature and moisture levels. You can use exterior caulk or foam insulation to seal up any gaps and make sure your shed is nice and snug.

Paint

Now for the finishing touch — maybe even the most fun part for some! Not me. I’m actually kind of sick of painting! But maybe you’re not. You’ll want to use an exterior paint and primer for both the interior and exterior of the potting shed. We went with white, and I would recommend you paint the interior white to help reflect as much light as possible. As for the exterior, feel free to follow your heart to make it your own!

Attach Polycarbonate to Rafters (figure 9)

Your roof is almost complete — all that's left is to add the roofing material. We went with polycarbonate because it's lightweight, durable, and lets in just the right amount of sunlight. Another cost effective option would be to use corrugated sheets of polycarbonate, which will do the job wonderfully. We went with a .093” thick polycarbonate clear polycarbonate sheet manufactured by Lexan (and available at Lowe’s) because of how similar it looks to glass while still being extremely weather proof and durable. The sheets measure 36” x 48” and can be scored and cut to size with a utility knife, meaning we were able to cut it to custom size for the front facade, which needed triangles of the material. We’ve been so happy with how it’s held up and how it looks, so even though it’s a bit pricey, we highly recommend!

Attaching the polycarbonate sheets to the rafters isn’t hard, but it’s a little awkward because the material itself bends, and the sheets are pretty heavy. Once you’ve scored and cut your pieces to size, you just screw them straight into the rafters. We ran 1x2s across every seam where the sheets met to help keep out water and then screwed down a strip of vinyl sheeting across the top ridge to prevent leaks. During super heavy rains we’ll some drip drops here and there, but overall is stays dry!

From left to right:

1.) Dewalt Miter Saw | A miter saw is an intermediate DIY’ers best friend! We put off buying one for a couple of years but since having taken the plunge our projects have become so much more professional. Perfect for clean straight and angled cuts.

2.) Dewalt Drill & Driver | The first investment piece we recommend any level of DIYer to buy! You’re gonna need it over and over and over again.

3.) Lexan Polycarbonate Sheeting | This is the exact product we used for the roof. We absolutely love the glass-like appearance of this product and the durable nature of polycarb.

4.) Exterior Wood Screws | You’re gonna need a TON of these for this project—buy extra because the last thing you want to do is run out and need to head to the store while in the middle of a work flow… speaking from experience.

5.) Spirit Level | Whenever you’re framing anything, in this case an entire shed, a spirit level Is your best friend that you should use with every new piece of wood you add. The last thing you want is for all of your hard work to result in a crooked, or worse, structurally unsound, potting shed!

6.) Speed Square | There are few other tools that you’ll find yourself turning to as often as a speed square. This is a great piece for quickly and accurately drawing straight lines and perfect right angles as well as making sure your joints are as square as possible. Don’t underestimate this thing because of how simple it is!

7.) Rafter Brackets | I’m sure it can be done without them, but for building my first ever roof I found these rafter brackets to be incredibly helpful as an angle guide as well as reassurance that my structure would be sound.

8.) Tool Belt | Okay aside from the fact that I’ve adopted a tool belt as essential to my personal aesthetic, there’s really no overhyping the usefulness of one of these, especially for a project like this where you’re up and down a ladder with tools in hand for several hours over the span of several days. Just get one, it’s smart and fuctional.

I know this may sound like an intimidating and long process, and to be honest, it kind of is! It took us working on it daily for about 10 days, even with a pretty meticulous plan. At the end though, it’s been so worth it. We love the extra storage space it’s given us and how beautiful and tranquil it makes the backyard. Not to mention it gives us a great place to start seeds in the spring!

If you have any specific questions about this project that were not answered in the post, please feel free to email us at hey@probablythis.com and we will do our best to get back to you timely with a response!

xoxo

Matt

& Beau & Fox & Barley & Rye

How to Build a Potting Shed: Our DIY Potting Shed Plans | Backyard Greenhouse Inspiration