Pull out the blueprints of the current house. A home garage can be attached or detached, but the house blueprints are necessary to avoid pipes or other complications that can ruin the project and the home.
Determine if the garage will be attached or detached from the house. An attached garage will be difficult to install on an existing home, but has several benefits that a detached garage does not have. However, a detached garage is usually easier to build.
Take measurements. The measurements of the area where the garage will be added need to be taken before a design can be drawn. Keep in mind that if a car is being put in the garage, the car should also be measured to ensure that the garage is wide enough and deep enough for the car. The size of the garage is especially important for larger vehicles like SUVs or vans.
Look at reference pictures and draw up an ideal design. Keep in mind that a good design should take the climate into account. For example, areas with heavy snowfall would want to avoid a flat roof. Designs can include one-, two- or even three-car garages, depending on space and personal preference. Put all of the details in the design, including your ideal garage doors. References can be found at any garage design website, such as Behm Design, or through regular image searches.
Detail the materials that should be used in the design. Materials will include the ideal flooring, the wall materials, the type of door and any other elements that are going to be added to the project. Materials for garages are often concrete for floors and wood for walls. The roofing is usually the same as the house.