When space gets tight, crowded homeowners can get desperate for ways to carve out space from nothing. Garage conversions abound in areas where real estate is expensive and neighbors are close. Plus, in this age of online platforms for short-term rentals, a converted garage is one way for homeowners to defray the cost of their mortgage while still living in the house.
Garage conversions appear to be the classic do-it-yourself home remodel project. With nothing in your way like load-bearing walls—and with the box seemingly already in place—a garage conversion may seem like an obvious choice. But a garage conversion does also have a number of significant downsides to consider before embarking on this project.
Pros and Cons of Garage Conversions
No loss of yard
Structure already built
Living space for family or friends
Loss of storage
Ungaraged vehicles age faster
Questionable value gain
Possible municipal parking requirements
Converting a garage requires more consideration than refinishing a basement because the positives are easily balanced out by significant downsides. With the basement remodel, by contrast, you can hardly go wrong. Except for the cost, improving an unusable dark space into one that is light-filled and usable is mostly a win-win project.
Garages are different, though. With the garage, you trade out a space that is usable for one or several things for a space that is usable for just one thing—living space. Garages are usable for the obvious use—storing vehicles—but it's easy to forget about the other uses for garages: storage space, laundry room, and work areas when the weather is poor.
Loss of Yard Space and Storage
Expanding into the garage preserves yard space, which many may prefer over building an addition. This means more living space but less yard for outdoor activities. Many people use their garage for storage, and even if you think getting rid of this extra space is a good idea, future buyers of your home may disagree.
Local Parking Requirements
Removing the cars from the garage may flout local requirements for on-site parking spaces. It's questionable whether a garage conversion will increase the property value: Many buyers place a premium on a protected parking space and this is lost with a garage conversion.
Gaining house value with a garage conversion might be losing value with your vehicles. Heat and sunlight promote oxidation, prematurely aging your vehicles.
Costly, Difficult Installations
Garage conversions might be more work than they may appear. Homeowners may plunge into a garage conversion based on the belief that little more is required than adding a few lights and flooring, as much of the structure (walls, ceiling, roof, and flooring) is already in place. On the contrary, garage conversions are costly, extensive, time-extended projects that are not quite on the order of building a new addition, but close to it.
Though difficult, a quality garage conversion can be done on a do-it-yourself basis, while building a detached addition is rarely done without professional help.
Yet Garage Conversions Are Trending Back
Despite many of these challenges, garage conversions are back in the news. Many communities that are pressed for space have begun to loosen or drop some restrictions on accessory dwelling units (or ADUs), a category that often includes full conversions of garages into living spaces.
Due to the rise of short-term house rentals, other municipalities have begun to look more critically at garage conversions—even if the area will not be rented out on the short-term market.
This dichotomy is very much on a local basis. Areas like San Francisco, Seattle, Portland, and Austin have loosened restrictions on ADUs. Other areas have kept restrictions in place.
Zoning and Legal Issues
Changing space meant for vehicles into habitable, safe, and a conditioned living space invokes legal and zoning issues. Each garage must go through a significant legal transformation when it becomes a habitable and new conditioned space.
One determiner used by some municipalities is whether or not adequate provisions are being made to replace the parking stalls eliminated from the garage.
The transformation from a garage to a conditioned space requires the garage to meet technical and legal standards that were not required when the area only housed vehicles or acted as a storage area. On top of that, most municipalities' building codes require a range of permits for the activities associated with this conversion: erecting or moving walls; running water supply or drainage; running sewer line; adding windows; installing a full electrical system.
Basics of Converting a Garage to Living Space
- Windows: Add enough window space to provide for natural light and air. In some municipalities, this means 5 1/2 square feet or a percentage of the total garage space.
- Ceiling: Maintain at least 7 1/2 feet of minimum ceiling height. This may be difficult to do if you are also raising floor height.
- Heat: Provide heating to maintain 70 degrees F. Retrofit heating options include extending existing central heating ductwork and installing electric baseboard or fan-driven wall heaters.
- Cooling: Some communities may have cooling requirements for rented properties.
- Light: Add at least one wall-controlled light switch. Per electrical code, garages already have at least one such switch.
- Outlets: Add or change wall outlets so that they meet minimum spacing standards. Basically, no cord should have to reach farther than 6 feet to reach an outlet.
How to Make a Garage Conversion a Comfortable Space
Insulate the Walls
Most garage walls and ceilings are not insulated. Drywall, if already installed, must be removed and insulation must be installed. Use conventional fiberglass roll insulation, rockwool, or sprayed foam insulation for the walls. Use fiberglass batts for the ceiling.
Raise the Floor Height
Garages tend to be built lower than the house. While not necessary, your home benefits if you match flooring heights by adding sleepers to elevate the floor covering above the concrete garage floor. Some localities may require floor insulation to be added. Even if floor insulation is not required, you may want this. Garage floors are always concrete slabs—not very warm or comfortable in the cold seasons.
Install Floor Covering
Even if you do add sleepers to raise the floor, you still will need a floor covering. Laminate flooring, engineered wood, tile, and luxury vinyl plank flooring are popular choices for garage conversions.
Install New Drywall or Finish Existing Drywall
Garages are usually installed with non-finish-quality walls. If the walls are insulated, you can keep the existing drywall but bring the finish up to higher standards.
Replace or Insulate the Garage Door
Should you leave the garage door in place or replace it with a wall? Many areas may require that the door be replaced with a wall. If you can keep the garage door, you should insulate the door. This is one major question you will need to address before converting the garage into a living space.
Hide Unsightly Areas
Non-load-bearing walls should be added around areas you do not wish to see, such as the water heater, furnace, laundry area, or storage. Sectioning out certain areas and leaving them unimproved is probably the easiest way to save money on a garage conversion.
Brown, Anne, Vinit Mukhija, and David Shoup. Converting Garages into Housing. Journal of Planning Education and Research. 2020;40(1):56–68. doi:10.1177/0739456X17741965