Developing a Garage Addition Building Plan and Estimating Garage Addition Costs

Though most homeowners prefer a large garage, it is very important during this phase to consider proportions between the existing home and the new garage addition.

To aesthetically look appealing from the road the garage addition length should not exceed two-thirds the length of the existing home. Otherwise the garage addition could overwhelm the existing home structure. The depth or width of the garage addition is less critical from an aesthetic standpoint, as it is usually less visible from the road.

The cross-sectional views should include from the concrete footings all the way to the peak of the roof. Each new transition from the footings up should be carefully drawn.

Examples include: the footing/foundation transition, the foundation/sill plate transition, and the wall/roof rafter transition.  The plans should also include a comprehensive bill of materials for the project. In addition, all property lines and appropriate setbacks should be clearly shown in the drawings.

Estimating Garage Addition Costs

Estimating the garage addition costs depends on who is building the addition. If the homeowner plans on acting as his or her own general contractor and performing some of the work (e.g. the framing) then costs will need to be calculated starting with the bill of materials generated during the garage addition planning phase. With a comprehensive bill of materials a homeowner can provide much of the list to any home improvement store where they can fill out the pricing information for the specific items for the garage addition project.  For specialty items such as garage doors, garage door openers, and in some cases lighting and plumbing fixtures (if required for the garage addition) the homeowner may need to contact specialty stores for pricing. The subcontractors may also be able to provide some unit pricing (e.g. garage doors).

Hiring a Garage Addition Contractor

If the homeowner is acting as his or her own general contractor and will require subcontractors, then it is important that they identify early the subcontractors and review with them the garage addition plans and development schedule.  Each subcontractor should provide a firm fixed estimate for the garage addition plan based on the drawings / sketches, and bill of materials. In addition their bid should also include start/complete dates for the garage addition project.

With garage addition plans and costs estimates in place the homeowner can then proceed with pulling permits and developing a fairly accurate garage addition building schedule.

Once permits have been approved, construction of the garage addition can begin. It is important to note, however, that even with the best plans in place things happen and schedules slip. To mitigate schedule slips a homeowner acting as his or her own general contractor should factor in some buffer to the schedule and always be looking ahead several weeks during the entire project. They should regularly check with suppliers to ensure building material will arrive when required and should occasionally check with subcontractors to ensure that their schedules are still in line with your garage addition project.

With these simple planning, budgeting and scheduling issues addressed prior to the start of the project, building a garage addition can be a positive experience both pre and post construction phase.