How to Make Your Own Garage Blueprints

Measure the space available for the garage, then compute the garage's length needed by multiplying the width of the widest car you have times the number of cars you want the garage to house.

Add to the figure you just calculated one additional foot for each car the garage will house. For example, if the garage will house three cars, add three feet to the length. This step adds space between the cars.

Write Step 2's figure as the garage length, and write the garage width and height as the length and height of the longest car you have.

Add two feet to the width and length dimensions, and 16 inches to the height dimension to allow clearance for car roofs and walking space between the cars and the garage walls.

Compare the space available from Step 1 with the dimensions you calculated in the previous step. If the space isn't big enough to house all your cars, increase the space available for the garage, or subtract cars from the calculations in Steps 1 through 4 and repeat those calculations.

Draw on graph paper a rectangle whose proportions are the same as the space you calculated. This rectangle represents the plan view, which is another name for top view, of the garage. If your dimensions from Step 4 were 20 by 40 feet, for example, you could make the rectangle 20 by 40 inches on paper. You can reduce this scale further to a size more convenient to work with. Dividing by two or changing measuring units are easy ways of reducing scale. For example, make the rectangle 10 by 20 inches, 5 by 10 inches or 10 by 20 centimeters.

Compute doorway size by adding six inches to the width of the widest car in the garage.

Erase gaps for the doorways the cars will pass through. Make these gaps in the long side of the rectangle facing away from the house. Make enough gaps for the total cars the garage will house. Ensure each gap's length is the figure you calculated in the previous step, and space all gaps evenly along the rectangle's edge.

Erase gaps representing the smaller doors for human access. Make these gaps in any of the garage walls where you require the access. At minimum, erase a doorway in the wall where the garage and the house meet.

Write the height of the garage by writing "Garage height" below the main floor plan of the garage, then writing the height you calculated in Step 4. Since top views of blueprints can't represent height information graphically, this information must be expressed numerically.

Label the edges of the rectangle with their measurements to complete the garage blueprint.