The choice to convert a garage to living space a cost-effective option for a new bedroom suite, kid’s playroom, guest or rental apartment and other potential uses.

This garage conversion guide is your roadmap for the project. It covers:

– Overview and initial planning

– Costs for typical projects and hiring a contractor

– Engineering and architectural needs

– Permitting requirements

– Steps to completion

– Possible timelines

Garage conversion begins with the need or desire for additional space. It is often chosen because the cost of an addition – building up or expanding the home’s footprint by building out – is two to three times the cost of converting space that has already been framed and enclosed.

This guide is about converting a 2-car or 2.5-car garage with 400 to 500 square feet.

Overview of Steps to Garage Conversion

Let’s start with the “big picture” of converting a garage to living space.

We’ll also address cost ranges for common projects, because, as ancient proverbs advise, it is important to count the cost at the beginning to know whether it is in the budget!

Two quick questions to begin:

Are garage conversions allowed? A call to your local building code department will provide you with the answer. Some municipalities have packets of information that spell out in detail what can and cannot be done and what documents you’ll need when applying for permits.

HOA? You should apply for HOA approval before beginning, if necessary. Not all HOAs allow garage conversion.

Step #1: Decide how to use the space. The more plumbing and electrical installed, the higher the cost. A family/recreation/TV room is a more affordable option than a bedroom suite with a luxury bath or a gourmet kitchen with a prep sink and full sink.

Step #2: Get professional consultation to determine what changes might have to be made to the garage structure, the home’s HVAC system, electrical and plumbing. This will help you determine if the desired project is possible and at what cost.

Step #3: Get written garage conversion cost estimates from local contractors. Select your contractor.

Step #4: Draw up garage conversion plans and associated documents such as a site plan showing the property and proposed changes.

Step #5: Determine or adjust your budget and choose a funding source, if you plan to get a loan.

Step #6: Apply for garage conversion permits. You’ll need one or more of the following permits – building, electrical, plumbing and mechanical.

Step #7: Once the project has been approved and the permits obtained, the contractor will get to work.

Cost Ranges

How much does a garage conversion cost? Project costs vary widely based on what you plan to do and where you live.

Maxable says, “Generally, you can expect a garage conversion to cost between $90,000-120,000…”

Budget Dumpster has a very different view, stating, “The average cost of a garage conversion is between $6,000 and $19,000.”

Someone didn’t do their homework – or maybe they are both right?

$10,000 and up: Projects with electrical but no plumbing or mechanical, such as converting the space to a family room or kid’s area, start at about $10,000.

$17,500 and up: Any project with a half-bath or full bathroom will start closer about here.

$25,000 and up: Adding HVAC along with plumbing and electrical will push the minimum cost closer to $25,000.

The upper end of the price range is determined by the quality and cost of the materials, windows, appliances and appointments chosen.

For example, you can convert the garage to a bedroom suite for $25,000 by choosing low-cost flooring, fixtures and decor. Suites outfitted with luxury items will double or triple the cost.

Total project costs of $100,000+ are not uncommon for high-end conversions in locations where cost studies, permitting and required architectural fees are high. Maxable’s numbers are for California where fees and regulations top the charts for cost.

Garage Conversion Start to Finish

The details of how to convert a garage are discussed in the steps below.

How to Use the Space

Here are the most common options, project basics and beginning prices for each.

Living Space – No Plumbing

This is a common option for small homes. People might feel they are “on top of each other,” and need more elbow room.

Popular options include a family/rec room, home theater, kid’s playroom or school room.

Here are basic options and requirements.

– The garage door can be left in place to maintain the same exterior appearance or it can be removed. The wall on the garage door side is framed.

The garage remodel will then proceed in this order:

– Windows are framed and installed.

– Wiring and junction boxes are installed in walls and the ceiling for lighting and outlets. If there aren’t circuits in the electrical panel to serve the room, a sub-panel will be added to serve the garage conversion.

– Insulation is added to walls, the ceiling and possibly the floor too.

– Drywall is installed.

– Finish lighting, electrical and flooring are installed.

– Paint, furnishings, etc. complete the space.

Pro Tip: Install an exterior door. This provides access directly to the room rather than through the house. This is an obvious requirement if the room will be rented out. But a door will be useful if the space is a guest room, in-law suite or used as a home office where clients are received.

Some homeowners consider an exterior door a security threat. If you feel that way, at least consider installing an egress window. It must have an opening of at least 5.7 square feet, large enough for a person to crawl out of, and meet other requirements.

One additional advantage of a door or egress window is that it allows the space to be used as a bedroom in the future. It gives you more versatility at little or no extra cost. Single-hung and double-hung windows that meet egress size requirements start at about 24” wide and 52” high to provide the minimum opening of 20” wide and 24” high.

Entry-level conversion: $10,000 – $15,000 Cost of garage conversion when no plumbing is included can be as low as $10,000 when cheap carpet or sheet vinyl is used, walls are painted and affordable lighting and furniture are purchased.

Midrange conversion: $15,000 – $25,000 is a more likely cost range when more and better materials are used. These could include quality laminate or luxury vinyl plank flooring, mid-grade vinyl windows from Jeld-Wen or Ply Gem and nicer decor, furniture and lighting. A basic-grade sliding glass doors fits within this budget too.

Upscale conversions: $25,000 – $50,000 is typical, though the sky is always the limit with a conversion. This range includes premium materials like tile or hardwood flooring, fine wood or fiberglass windows and doors and nice fixtures. A home theater with $7,500 to $15,000 worth of equipment might also fit into this budget.

Living Space + Half-bath (or Full bath)

This conversion is the same as above with the addition of a small amount of plumbing.

The cost of adding a half bath starts at about $3,500. Cost varies based on the complexity/expense of the plumbing required to tie the waste lines into the main sewer line of the home. When it involves cutting the foundation concrete, cost is on the high end.

Pro Tip: Consider installing a full bath instead. The cost will increase by as little as $2,500 over a half-bath. For the money, you’ll enjoy the versatility of a full bath plus the option of using the space as a bedroom suite in the future. And a full bath brings a better return on investment than a half-bath.

Entry-Level half or full bath: $3,500 – $6,000 when affordable materials like sheet vinyl flooring and a simple fiberglass tub/shower assembly or glass stall are used.

Midrange half or full bath: $5,000 – $15,000 for a bath with good-quality LVP or engineered hardwood flooring and some ceramic tile. Adding one luxury feature such as a jetted tub, steam shower, heated towel rail, radiant heat in the floors or premium countertops will push the project over $10,000.

Upscale half or full bath: $15,000 – $60,000 for a bathroom with full ceramic tiling and multiple luxury features plus quartz, granite or marble countertops.

Did you know? The more you spend on a bathroom, the lower the Cost to Value will be. That’s a term for return on investment used in the building industry. According to the well-respected annual survey done by Remodeling Magazine, a midrange bathroom remodel brings a 67.2% return. Pulling out all the stops on an upscale bathroom brings a return of 60.2%.

Kitchen and Eating/Dining Area

This conversion is most common in homes built in the 1960s and earlier when small kitchens were more common and many lacked dining space.

It is also popular with gourmet cooks and homeowners big on entertaining.

You’ll need the “whole works” including electrical wiring, water supply and waste plus, if you want gas appliances, gas line and connections. A vent and hood will be useful for discharging cooking odors too.

Major price factors for any kitchen are:

– How many cabinets you use and their quality

– Whether there is an island and whether it has plumbing and power

– The total square footage of countertops and the type you use

Entry-level kitchen: $12,000 – $24,000. This is a good choice for modest homes. The kitchen can be attractive and add loads of functionality to the home even if you use vinyl flooring, builder’s grade appliances, laminate countertops and cabinets “off the shelf” from Home Depot. The survey sited above says a kitchen in this cost range brings an 80.5% return.

Midrange kitchen: $24,000 to $50,000. In midrange garage conversions, you can use decent-quality materials throughout or splurge in a few places. A high-end gas range or quartz countertops can fit in this budget if you keep other costs under control.

Upscale kitchen: $50,000 – $100,000+. If you’ve shopped custom cabinets, countertops, fixtures, sinks, appliances, dining furniture and other materials, then you know that a price tag of $100,000 isn’t hard to reach. Cost to Value of garage to kitchen conversions in this range are 59% to 62%. That means if you spend $100,000 on a kitchen, your home’s potential market value will rise by $59,000 to $62,000.

Pro Tip: The kitchen must fit the rest of the house and neighborhood standards. Adding an $80,000 kitchen in a home that cost $125,000 is an investment that will return less than 50%. Don’t overdo it.

The opposite is just as true. If you do a cheap garage conversion in a very expensive home, it will hurt the home’s value. Either scenario will make the home harder to sell. This principle holds for any remodeling job.

Apartment with Kitchen and Full Bath

The number of multi-generational families living in the same home is growing.

Savvy homeowners are renting out apartments by the night or leasing them by the year.

For these reasons, a garage conversion to a full apartment is an investment.

It will involve everything covered so far plus a kitchen. There will be more interior framing to accommodate the bedroom, even if the rest of the floorplan is open.

Entry-level apartment: $21,000 – $35,000. This garage conversion includes affordable materials like those discussed above, low-cost fixtures and inexpensive appliances.

Midrange apartment: $35,000 – $60,000. This budget allows you to choose midrange components across the board or allocate money toward some premium features like nicer appliances as long as some lower-cost features like affordable carpet or vinyl are used.

Upscale apartment: $60,000 – $120,000+. A well-appointed apartment is a premium garage conversion. With a large budget, you’ll have more flexibility in how to allocate it. A mix of midrange and premium components will give you a starting budget in the $60,000s. Using the best of everything pushes it above $100,000.

What about heating and cooling?

If your home’s HVAC system is properly sized, it won’t have the capacity to serve an extra 400-500 square feet.

In most climates, you’ll want central heating and air conditioning. The simplest solution is a ductless mini-split heat pump system.

The installed cost of a system to serve that much space will be $3,000 to $5,500 in most situations. The major cost factor will be how many indoor units are required. In an open floorplan, you’ll need just one. In an apartment, two or three will be preferred.

Consult the Pros

An experienced general contractor will tell you what electrical, mechanical and plumbing changes are required for the garage conversion you have in mind.

They will also know whether projects like what you have planned are typically approved in your community.

Large remodeling firms have in-house design services that are very useful. Smaller contractors can refer you to local interior designers. Getting design advice isn’t required, of course, but skilled designers help their clients create conversions that maximize usefulness and enjoyment.

Most garage conversions do not include structural changes other than potentially adding windows and a door and framing in the garage door opening. In most communities, you won’t need the services of an architect or engineer to plan these features.  

Get Written Estimates & Choose your Contractor

This step is naturally combined with the one above. We’ve divided it for clarification.

If you’re following this plan, you’ll have talked with at least one garage conversion contractor. It’s time to talk to a few more and get written estimates from each.

You might have to pay for estimates. If contractors are busy where you live, they’ll probably charge $100 to $250, maybe more, for a garage conversion estimate. This covers the 2-5 hours they put into determining construction factors and costs. And it helps to weed out homeowners that aren’t serious about going forward, but just want to explore pricing.

Paying for estimates is a small cost for the advantage of hearing ideas and advice from several experienced professionals. A proverb proved correct over the centuries says, “Without counsel plans fail, but with many advisers they succeed.” Get input from multiple sources when gathering estimates. The wisdom of experienced contractors is invaluable.

By the way, most contractors put the cost toward the job, if they get the job.

Choose a contractor with a proven track record of:

– Quality workmanship

– Staying within budget

– Using the promised materials

– Cleaning up the job site daily

– Being responsive to customer concerns after the job is completed

– They should also be licensed, insured, and bonded.

Produce Drawings of the Garage Conversion

The building department will have to approve your project. Your application for a permit will include at least 2 drawings in most communities.

A site plan: This drawing is also called a plot plan. It shows the “big picture” of your property’s footprint. It has the outline of your home and garage, driveway, adjoining streets and other major features such as a sidewalk or permanent shed.

The cost of a site plan starts at about $100 when purchased from a site like ours that specializes in them. You can get essentially the same drawing from an architect for multiple times the cost.

A floorplan: This drawing shows how space within the garage will be allocated. Depending on how “picky” your local building department is, the floorplan will have to show the position of new walls and doors, wall thicknesses, insulation R-value, utilities, and other details.

A cross section or elevation (not required in some communities): This is the view from the side, as if viewing the garage conversion without walls. It shows wall and door heights, window locations and similar details.

Many building code departments accept hand-drawn floorplans and cross sections as long as they are accurate and clear. If not, the contractor should be able to supply these drawings using software designed for the purpose.

This garage conversion information package given to homeowners in Beaverton, OR shows examples of these drawings.

Finalize your Budget and the Plan

The information above should give you a very good ballpark idea of your costs.

But now that you’ve received written garage conversion cost estimates, you’ll have the information needed to tweak the plan to fit your budget.

– When estimates are lower than expected, you can upgrade the plan and stay on budget or keep the same plan and save money.

– When estimates come in higher than expected, you’ll have to use cheaper materials or re-allocate funds to bring cost estimates in line with their budget.

This process is best done in consultation with the home remodeling contractor. The finalized plan the contractor writes up should include details about construction materials, finish materials like flooring and countertops, lighting/kitchen/bathroom fixtures and more. The more detail, the less potential for conflicts as the work progresses.

Both you and the contractor should sign the final agreement about the scope and details of the garage conversion.

Apply and Receive Approval & Permits

Your contractor will assist you in the application process. Most will also apply for permits.

Here is the Garage Conversion Carport Enclosure application for Austin, TX. It’s a good representation of an application and includes a checklist of the documents and drawings required.

You’ll encounter a list of fees. Here are typical ranges:

Application fee: $30 – $100

Project plan review: $100 – $400+

Project revision fee if changes are made once the project is approved: $50 – $200

Consultation fee (if needed): $100 – $200 per hour

Once the application is approved, you’ll have permit costs:

Building permit: $75 – $600. Many communities charge permit fees based on the square footage of the project.

Electrical permit: $50 – $450 based on the city and scope of the project.

Mechanical permit for heating and air conditioning work: $75 – $600

Plumbing permit for water supply and waste/sewer and/or gas lines and connections: $50 – $500

Is Building Up an Alternative?

Definitely, but a costly one. Many homeowners tear the roof off the garage and build above it. The advantage is keeping the indoor parking that a garage provides.

The downside is cost. Expect these costs in addition to what you see above:

Demolition permit: $100 – $350

Dumpster rental: $500 – $1,000

Demolition labor: $800 – $1,500 or $2 to $3 per square foot of roofing

Framing, siding, windows and roofing for the second level: $14,000 – $20,000

At this point, you’ve got framed but empty space at a cost of about $15,500 to $23,000. See the costs above to determine the price of completing it as desired.

Timeline – How Long Does a Garage Conversion Take?

The planning phase often takes longer than the construction phase. Here are common timeframes for each.

6-12 Months: Start thinking through how to use the space at least 6 months in advance of construction. You don’t want to rush this decision. Research options. Browse galleries online of completed conversions. Start thinking about materials. Ask friends for contractor suggestions.

3-6 Months: It can take up to 6 months to get approval for projects when the building industry is hot. Applications get stacked up. Inspectors are backed up. Not providing the correct information and having to resubmit it can put your application at the bottom of the stack. Building permits in most areas are good for 180 days. Get an early start on the process. Even if you receive the building permit months before construction starts, the permit can be renewed or extended easily and for a small fee.

Contractors: You should start interviewing contractors during this period. The best contractors often have project start dates 2-4 months out.

Materials: This is also the time to order any made-to-order items. These include custom cabinets, countertops and windows. Most of these items require 3-6 weeks of lead time, possibly longer. Of course, if you’re not as choosy or have a lower budget the items can be bought off the shelf without having to order them ahead of time.

The construction phase will vary from a few weeks to a month or more based on the scope of the project. A good contractor will have subcontractors like flooring installers and painters lined up in the right sequence to reduce downtime delays. But they can still happen. For example, the electrician needs the wall cavities open for their part of the project. If they get a week behind on another job, it pushes everything back. You can’t install drywall before electrical. You can’t (or shouldn’t) install flooring before drywall, and so on.

Living space w/o plumbing: 1-3 weeks. When all materials are available, the crew is large and experienced and subcontractors have availability, the work can be completed in a week, though 2-3 weeks is more common. With delays, it could be 4-6 weeks.

Living space with a half or full bath: 2-5 weeks with the same time factors as above. Delays can mean 6-8 weeks.

Kitchen: 4-6 weeks. When electrical, plumbing and mechanical subcontractors all have work to do, the scheduling becomes more difficult and slows the project. Unfortunately, 10 weeks on a kitchen project isn’t uncommon.

Full apartment: 6-10 weeks. The complexity of scheduling and the time-cost of delays is magnified when “everything” has to be done. Depending on how versatile the contractor’s crew is, as many as 5 or 6 subcontractors will be used when converting a garage to a full apartment. That produces scheduling challenges and increases the risk of delays. 

Note: Here’s how we can help: 24hplans has a team of highly-trained, professional architects and drafters who can prepare any kind of site plan in the shortest amount of time possible, so that you can easily obtain that building permit and get on with your project. Use the promotion code: 24hplans-20off to get a 20% discount off any package. — Please note this is a limited time offer, exclusive to the readers of our blog. This offer is not being advertised anywhere else.