How do I Build a 10 X 20 Garage?

A free-standing garage will provide useful storage as well as protection for your vehicle.

A free-standing garage is an excellent way to add storage to your home. In addition to protecting a car it can also provide a place to stash those items that are used infrequently. A garage can serve double-duty as a work area for weekend projects and add to the resale value of your home.

Things You'll Need

• Garage blueprint
• Pencil & paper
• Stakes
• Measuring tape
• Shovel
• Cinder blocks or concrete forms
• Cement mix
• Water
• Crushed stone
• Tamper
• Optional sand
• Rigid insulation
• Polyetheline vapor barrier
• Wire mesh
• Concrete for floor
• Broom
• 2 by 4-foot studs
• 2 by 6-foot studs
• 2 by 10-foot framing studs
• Optional windows
• Garage door
• Carpenter's square
• String
• Anchor bolts
• Nails
• Hammer
• Roof trusses
• Furring strips
• 1 by 4-foot board
• 1/2-inch plywood
• Drip molding
• Roofing paper
• Roofing tacker and tacks
• Shingles
• Exterior vinyl or wood
• Optional electrical outlets/light
• Rolled insulation
• Drywall
• Paint

Instructions

Lay the Foundation

1. Determine the location for your garage and pound stakes into each corner. Prepare a site plan and a blueprint of the garage structure and obtain the proper building permits.

2. Dig a trench around the perimeter of the structure 24 inches wide and 4 to 5 feet deep. Prepare cement mix as per the manufacturer's directions. Pour a 24-inch wide footer by 3 inches deep and let it set up overnight.

3. Using cinder block or a concrete form, build up the foundation to 6-inches above the grade. Let this dry completely. Backfill with a base of crushed stone, and then add excavated dirt.

4. Tamp down the interior soil, adding sand if needed, to create a compact surface. Add rigid insulation 2 feet down on the inside of the blocks or concrete and 2 feet into the interior. Lay down a polyetheline vapor barrier.

5. Add a layer of wire mesh over the vapor barrier. Pour the foundation concrete to 4 inches in height. Before the concrete sets completely, run a broom over the top to give it a textured, non-slip finish.

Build the Frame

1. Build the side-wall frames first, adding openings for any windows and doors you may have. Build a header over each opening out of 2 by 10-foot framing studs. The remainder of the walls should be built from 2 by 4 studs, placed vertically every 16 inches on center. Anchor the wall frames to the foundation with anchor bolts. Check for level and plumb as you go. Build the back wall, and nail the sides and back together. Brace the walls with 2 by 4 studs until the roof is in place. Check for square by running a string line the diagonal distance from one corner of the frame to the other, making sure they are the same measurement.

2. Build the front wall where the garage door will go. The smallest garage door measure 8 feet in width, so your measurement should allow for one foot on either side. Frame a header over the top of the door with a 2 by 10 framing stud. Frame the sides with three 2 by 6 studs nailed together. You might also consider using steel framing studs on the garage door sides, especially if you elect to use the wider 9 by 7-foot door. Brace this wall to the rest of the frame.

3. Install roofing trusses every 24 inches on the top plates of the framed walls. Nail the trusses onto the top plates of the walls. Nail furring strips between each truss at the top peak, and at the bottom of each truss to brace them together. Finish off the reinforcement by installing a 1 by 4-foot board down the center of the trusses. Build roof gables to match the pitch of the trusses, and install them on the front and the back of the garage.

4. Cover the roof with 1/4-inch plywood. Nail drip molding along the sides of the roof. Tack down roofing paper and nail down shingles.

5. Install 2 by 6-inch fascia boards to cover the tails of the trusses.

Finishing

1. Add plywood to the framing and cover with exterior treatment of your choice. Install the doors and windows as per manufacturer's directions. Add decorative trim around the windows and garage door to finish the look.

2. Install electrical outlets and overhead lights, if desired. Add rolled insulation between the studs on the inside of the garage. Finish off the walls by putting up drywall.

3. Paint any exposed wood on the outside with a quality exterior paint. Prime and paint the interior walls.

4. Add sheets of plywood on the floor of the trusses for overhead storage.

References

• Home Garage Help: How To Build A Garage
• Rona: Your Own Free Floor Plan
• Dimensions Guide: Garage Door Sizes