Summer’s here, yea! All the outdoor stuff is everywhere, yuk! Okay, you’re finally ready to start building that shed for all your outdoor stuff. That’s great, but where to start? Here are the 5 most important things to know before you start building any shed project.
1. Start With a Sound Foundation
Doesn’t matter how well built your shed is, if it’s set on a weak base, it won’t last. Most sheds can be supported by an on-grade foundation, which consists of solid concrete blocks or pressure-treated wood timbers set directly on the ground. The concrete blocks or timbers (aka skids) must be leveled and spaced closely enough to properly support the shed’s floor frame. Note that it’s important to use solid concrete blocks, not hollow wall blocks, which can easily crack. Also, you should never build a shed in a wet, low-lying area, and if the site is exposed to occasional rainwater runoff, set the blocks or timbers on 2 in. to 4 in. of gravel. That’ll help protect the foundation from erosion. Larger sheds, typically those more than 200 sq. ft. in size, require permanent foundations that extend down to the frost line. They’re usually constructed of poured-concrete piers or buried wooden posts. (Check with the building department for specific code requirements and frost-line depth in your area.) Finally, if you’re using buried wood posts or on-grade timbers, be sure to cut them from pressure-treated lumber rated for “ground contact.” Treated wood rated for aboveground use isn’t intended for burial or direct contact with the ground, and will eventually rot.
2. Allow for Air Circulation
Water is wood’s worst enemy. Given the right circumstance and enough time, excessive moisture can rot framing, warp floors and doors, corrode hinges and breed mold and mildew. Fortunately, there’s an easy remedy. First, be sure that the lowest wood member–the mudsill–is at least 6 in. above the ground. That’s sufficient space to allow fresh air to circulate under the shed. Leave at least 2 ft. to 3 ft. of space around all sides of the shed. Building it too close to trees, shrubs, fences or other structures will block out sunlight and wind that help keep a shed dry. Plus, having clearance space around a shed makes it much easier when it comes time to paint or make repairs.
3. Build a Weather-Resistant Floor Frame
There are several ways to economize when building a shed: Install three-tab roof shingles instead of architectural shingles, or use grooved-plywood siding in place of cedar bevel siding. But don’t ever skimp on the building materials used for the floor frame or plywood floor deck. I can’t tell you how often I’ve walked into a shed and found the floor to be dangerously spongy. One building in particular had a floor so badly rotted it felt like one of those inflatable moonwalk attractions you see at carnivals. When building the floor frame, which includes the mudsill, floor joists and perimeter band joists, use 2 x 6 or 2 x 8 pressure-treated lumber. Many prefab sheds use untreated construction-grade lumber for the floor frame, which is fine–if you plan to keep your shed indoors. Even in ideal conditions on the perfect site, a shed floor will be exposed to some moisture, and in time, untreated lumber will rot. For the shed’s floor deck, use ¾-in. exterior-grade plywood; anything thinner will flex between joists. (Note that a double layer of ½-in. exterior ply is okay, too.) If you plan to store heavy items, such as a lawn tractor or woodworking machines, consider using ¾-in. tongue-and-groove plywood. This costs slightly more, and is a bit more troublesome to install, but its edges lock tightly together, creating a rock-solid, rigid floor. In areas with excessively high moisture and large numbers of wood-boring bugs–such as Florida, Alabama and the other Gulf Coast states–consider using pressure-treated plywood for the floor deck. It’s particularly resistant to moisture and insects.
4. Use Low-Maintenance Materials
Most homeowners barely have enough time to keep their homes in shape, never mind their sheds. That’s why it’s smart to choose low-maintenance materials for your shed. You usually need to pay a bit extra for these, but they’ll save you time and trouble in the long run. For example, the last three sheds I built were trimmed with white PVC trim boards instead of painted cedar 1 x 4s. This new plastic lumber, which I used for the rake, fascia, frieze and corner boards, is impervious to bugs, warping, splitting or decay, and it never needs painting. Other low-maintenance options include: vinyl or aluminum windows, faux-slate roof shingles, fiberglass or steel doors, composite decking for steps, and fiber-cement siding. (I don’t usually recommend aluminum or vinyl siding for sheds; neither material is rugged enough to survive the inevitable beating outbuildings take.)
5. Get Smart About Door Size and Placement
I’m always surprised at how little forethought most backyard builders give to the shed’s doors. After all, there’s no sense in building a shed to store a particular item, such as a lawn tractor or wheelbarrow, if you can’t fit it through the door. I saw a shed recently that had its doors removed. When I asked why, the homeowner explained that he framed the doorway wide enough for his riding lawnmower, but didn’t take into account the amount of space taken up by the hinged inset doors. So, he had to remove the doors to fit the mower inside. (He’s in the market for a skinnier mower.) The two types of doors most commonly used on outbuildings are hinged and sliding, and both work well. Hinged doors take up less space and close more tightly and securely. Sliding doors are easier to install and glide completely out of the way. They require additional wall space, however, to slide over when opened. Door placement is also important. You often see doors placed on the gable end of the building, which looks nice, but makes it virtually impossible to reach items stored at the rear of the shed. A better alternative is to put the door on the long side wall, so that you’ll be able to access items to the right, left and back. Another option is to install doors on both gable-end walls, so that you’ll be able to easily reach items from either end of the shed.
Remember, you are investing lots of time and money in your project, so don’t go cheapo! You want to build something that you are proud of and will last for years, not become a money pit because you were cheap in the beginning.