Prepare a site. Clear the area of any tree roots, big rocks or other impediments. Check the drainage and make sure the area slopes slightly away from the shed site in all directions. Measure with a tape measure and outline a 10-by-16-foot foundation area using wood stakes and builder's twine. Make sure the corners are square with corner measurements; once diagonal distances are equal, the site will be square.
Excavate the area with a shovel at least a foot deep. Lay down landscape fabric and cover the area with medium gravel, about 1/2 inch in diameter, 8 inches deep. Rake the gravel roughly level and compact it with a hand tamper.
Make concrete forms of 2-by-4-inch lumber 10 feet by 16 feet; make sure corners are square, an exact 90 degrees. Brace the forms with stakes in the ground every two feet and secured with angled "kicker" stakes from the upright stakes into the ground. Fill the forms with concrete; have the concrete delivered or rent a mixer so you can make the pour in one continuous session. Level the concrete with a 2-by-4 across the forms, pulled end to end. Let the concrete sit until water appears on the surface, then smooth it with a mason's trowel. Let the concrete set for a couple of days.
Build walls with 2-by-4s, a bottom plate of pressure-treated lumber and a top plate and vertical studs set 16 inches apart. Make the end walls to fit inside the two side walls. Nail studs with a hammer with two framing nails in the top and bottom of each stud through the plates. Make a rough door frame in the front wall. Cut a 2-by-6-inch header board to go across the opening and fasten it with a full stud on each side, nailed to the ends of the header, and a short stud on each side from the bottom of the header to the base plate. Cut out the base plate to fit the opening.
Raise walls, on top of a thin moisture barrier under the bottom plate, and set them plumb; use a level. Brace walls temporarily with 2-by-4s nailed to studs and to stakes in the ground outside. Nail walls into the concrete slab with concrete nails and nail studs together at the corners with framing nails. Remove the temporary braces. Cut wall caps, 2-by-4s to go over the top plates, so the end wall caps overlap the sides, to tie the walls together.
Frame the roof the easy way, with prefabricated roof trusses. Raise each end truss into place and set it plumb, nailed to the wall caps on each side, then install a ridge board between the trusses. Add other trusses set 24 inches apart, nailed to the wall caps and the ridge board. Make sure the ridge board is level and all trusses are plumb.
Sheath the walls and roof in oriented strand board (OSB), nailed to the studs and trusses. Cover the roof with roofing paper and shingles. Put siding as desired on the wall (use wood or vinyl) and finish by adding any trim boards. Install a pre-hung door in the rough door opening.
Things You Will Need
- Tape measure
- Wood stakes
- Builder's twine
- Landscape fabric
- Hand tamper
- 2-by-4-inch lumber (some pressure-treated)
- Framing nails
- Mason's trowel
- Moisture barrier
- Concrete nails
- Roof trusses
- Roofing paper
- Siding (as desired)
- You can make your own trusses by cutting rafters and securing them with gussets, metal or wood connectors, at the peak, and cross or collar ties across the rafters about a third of the way down from the peak.
- Build walls on the slab and set them aside until time to erect them.
- Add windows if desired by framing rough openings, similar to the door opening but with a bottom sill.