Having a detailed garage plan is a prerequisite for anyone building a garage -- pro or do-it-yourselfer -- because it's needed to get a local building permit.
You don't have to spend a bunch of money to have a plan drawn up. Lumber yards and mail order services sell a range of plans.
However, if you plan to closely match your house or want some custom features, consider hiring a draftsman to tailor your plans. Our garage plan was purchased from a design service for about $50.
Some things to consider when planning:
- Underground/Existing Utilities (always have the area marked before digging)
Attached/Detached or future attachment to house
Window and Door Location
Finished Storage Space
We decided on a two-car, detached garage with dimensions of 22' x 22' with built-in attic storage space.
Our layout incorporated plans to later attach the garage to the existing house, so frost footings (footings deep enough to resist frost upheaval), slab height one step below house floor height, and a retaining wall were planned.
Once the plan is worked out, it needs to be submitted to your local building authority for a building permit. With permits come inspections of footings, framing, wiring, and final completion. So get the footings and framing checked before you proceed to cover them up.
Consider the overall slope and drainage of the garage area. Is a retaining wall needed to support a nearby hill? Is extra excavating needed to funnel water away from the foundation?
Wherever you decide to put the garage, get the area marked for underground utilities. If you have an underground sprinkler system, make sure it's relocated if necessary.
Stake out the area to be graded.
Grade the area level and stake and outline the foundation with twine.
NOTE: The final grade should be backfilled to slope up slightly to the foundation once it's in.
Dig out the footings to the proper depth. Again, this could be 12" to 48" depending on your situation. Our footings were pretty deep, requiring survey equipment and a backhoe, so we hired an excavator to do the digging.