How to Build a 3 Car Garage With Storage

Draw up detailed plans for your three-car garage. Keep in mind that the minimum width for a three-car garage is 30 feet, so having sufficient room for storage on one or both sides of your garage will require that your build your garage between 32 and 34 feet wide, if not larger depending on your needs. The depth of your three-car garage should be 24 feet deep or more.

Make sure that your plans comply with your local building code. Submit your plans, an application and any other necessary materials to your local building department in order to receive a building permit.

Set the lines for the foundation of your garage and excavate the site. Pack down the soil and fill it with gravel to be the base layer of your foundation. Construct your garage foundation forms by 2-inch by 12-inch boards and place stakes at intervals of 36 inches all the way around. Insulate the garage floor by using rigid foam board and use rebars to strengthen the concrete of your foundation.

Place anchor bolts into the wet concrete of the garage foundation for the bottom plates of each wall, at consecutive six-inch intervals. Let the concrete dry completely before beginning the framing process.

Lay out the bottom plates (treated 2-inch by 4-inch lumber posts) of each wall and mark them according to the anchor bolt placements. Drill holes for the anchor bolts, but do not secure them in place yet. Place sill foam over the anchor bolts to act as underlayment between the bottom plates of the walls and the concrete. Frame the walls using conventional standards for ease of construction and also to ease the amount of waste materials.

Cut the top and bottom plates the same length. Cut studs out of 2-inch by 4-inch lumber to measure eight feet long. Place the top and bottom plates side by side and mark them both for stud placement. Studs should be placed 16 inches on center. Remember to include the rough openings for your windows and doors, according to the products' guidelines for their specific dimensions. Build the headers for the doors and windows using two two-inch by six-inch boards. Brace the walls with scrap 2-inch by 4-inch lumber.

Use a prefabricated beam or construct one out of 2-inch by 12-inch boards to act as the headers for the overhead doors of your garage. Use trimmer studs on both ends to support the headers and double the top plates using 2-inch by 4-inch boards. Cover all of the wall sections with plywood sheets except for the locations of windows and doors, of course.

Use prefabricated roof trusses to construct your roof. Place them at 24 inches on center and sheathe them with plywood. Apply an ice and water barrier before adding the roof shingles. Finish the garage by adding insulation, siding and the doors and windows of your garage according to each manufacturer's guidelines.