How To Assess Your Potential for a Garage Conversion

convertgarageA garage conversion can be one of the quickest and most affordable ways to add living space to a home. The foundation, walls and roof are already in place. The wiring is often sufficient. And if the garage is attached to the house, the entry already exists.

In many houses, a well-planned garage conversion can create a new room or rooms that blend seamlessly with the existing house. The process should begin with a careful assessment of the garage and the problems and promises it holds.

Garage Door

The biggest question facing most garage conversions is what to do about the garage door. Once the door is removed, the resulting space needs to be filled in so that it both blends in with the rest of the house and provides a useful service to the new living space. Possible options include installing a patio door or framing a new wall that includes a large window.


A typical garage sits on an uninsulated concrete slab, which may be several inches below the floor level inside the house. The slab may well be sloped toward the garage door or a floor drain. With these circumstances, you will want to consider filling the bottom of the garage door opening with a curb that will keep water out of the converted space and protect wall framing from moisture. You will also need to decide if the floor should be leveled.

Heating and Cooling

If the garage is attached to the house, you may be able to extend the existing heating and cooling system into the new space. If that is not possible, look into an independent system (heat can be supplied by electric baseboards, gas space heaters or woodstoves, for example, while a room air conditioner can handle warm weather). Add insulation to walls, floor and ceiling before deciding how to heat and cool the space.


If you expect to substantially increase electrical usage in the converted space, consider adding at least one new 20-amp circuit. Wiring to a detached garage can be run through an underground conduit.


This can be the biggest headache of a garage conversion. Getting water supplied to the garage may be easy, but drainage could present major problems. Check with a plumber about your options. If you are lucky enough to have a laundry/utility room connecting the garage to the house, you might be able to turn it into a bathroom.

Loss of Storage and Parking

Much of what is currently stored in your garage could go into a new shed, the basement or attic, or be sold at a garage sale. To protect your vehicle from the elements, consider building a carport.

Blending In

Think hard about to make the exterior of the converted space look like it has always been a part of the house, rather than an afterthought. Try to match the siding, colors, window and door styles and the landscaping.


Checklist for a Carport to Garage Conversion

Carports are inexpensive to build, but they aren’t nearly as useful as garages, nor secure. If you would like to convert your carport into a fully enclosed and secure garage, here are some tips on what to look for and think about.

  • Check your local building code and HOA regulations. Find out if the project is allowed and what you may need to do to get a permit. For example, an attached garage will likely need a fire-rated wall on the house side.
  • Measure the slab. At a bare minimum, a garage should be 20-ft. deep, with a width of 10 ft. for one car and 18 ft., 6 in. for two cars. A more comfortable garage would add 2-4 ft. to each dimension.
  • Check the height. Will there be room for a header above the garage door opening? A standard garage door requires a rough opening 8 ft., 1 in. high, with a 2×8 or 2×12 header spanning the opening.
  • Carports are built with gable roofs and shed roofs. Try to imagine what the converted space will look like with the existing roof. A shed roof may look fine for your carport, but not particularly pleasing when it is enclosed.
  • If you plan to keep the existing roof, have a contractor, home inspector, or structural engineer examine it. If the roof is in poor condition, you might want to remove it and start your garage project from scratch.
  • Check the slab. Is it structurally sound? Is the footing wide and deep enough? Though the slab surface may seem fine, it may not necessarily meet current code requirements. Once you apply for a new building permit, you may be required to address that issue.
  • Determine in advance how electrical service will be delivered. And if you want to add plumbing for laundry or other purposes, talk to a plumber about your options before proceeding.

Planning for a New Garage

If you are having a new garage built, there’s a good chance that the builder will suggest 9-ft. wide by 7-ft. high doors (assuming you are planning one door for each vehicle in the garage). That’s a good size for most of us, but what if you happen to have a large truck, with large mirrors projecting from the sides or a snowplow on the front. Many such trucks have lost those mirrors trying to squeeze into a 9-ft. wide opening. In this case, you might want to give serious though to going with 10-ft. wide doors, and perhaps increasing the height to 8 ft.

Another big decision to make when planning a new garage is whether or not to have it attached to the house. Though attached garages are the norm these days, there are several benefits to a detached garage. Particularly if you are accommodating unusually large vehicles, a detached garage may provide more latitude in design.

How To Measure for Garage Doors

If you are replacing a garage door, the easiest way to determine the size you need is to measure the existing door. If you happen to have a doorless garage, you will need to carefully measure the width and height of the opening. You will also need to check the clearance above the opening to ensure that there is sufficient room for the garage tracks to be installed.

This is assuming that you plan to buy and install the garage door yourself. If you are going to let a professional handle the job, let him determine the exact size of door you need.

Changing the Size of a Garage Door Opening

From a structural standpoint, it is easy to reduce the size of the opening in a garage, thus creating the need for a smaller garage door. Unfortunately, few people have any need to do this. Instead, it is much more common for homeowners to need a larger garage opening, primarily because their larger vehicles just don’t fit well through the existing opening.

Enlarging a garage door opening is often nearly impossible without substantially increasing the size of the garage. The biggest obstacle is usually the headroom above the existing opening. The span above the opening is framed with a long header that will have to be raised (or more often rebuilt). If there isn’t enough room above the opening, this can’t be done without raising the roof of the garage. That’s a big, but doable, job. You also need to consider allowing room for the garage door opener.

You also need to account for the depth and width of the garage after the opening has been enlarged. Just because you can get your bigger vehicle through the doors does not mean you’ve improved the garage. In fact, you may now have too little room on the sides and in front of the parked vehicle to move, much less to use for storage.

How to prepare your Garage Floor for a Conversion

When converting a garage into living space, the first big job usually is removing the garage door. The next step is to fill in that big open space with some combination of walls, windows and doors.

Garage walls are either framed directly on the slab or on a 6- to 10-inch curb around the perimeter. If your walls sit on a curb, you need to extend that curb through the opening. The curb helps keep water out and it also protects the wood framing from moisture damage. You should be able to determine whether or not you have a curb by examining the sides of the garage opening after removing the jambs.

Here’s How:

  1. Before you begin, inspect the condition of the concrete slab in the garage. If it is badly damaged, make the the necessary repairs before proceeding. If you aren’t sure how to make that determination, seek the advice of a construction professional.
  2. The first step in extending a concrete curb is to insert some reinforcing bars (“rebar”) into the sides of the existing curb. This will help tie the new and old sections together. With a hammer drill, which you should be able to rent (if not borrow) and a 1/2-inch masonry bit, drill two holes about 6 inches deep into each curb. The holes should be centered, one on top of the other. Tap 12-inch pieces of rebar into each hole with a small sledgehammer or large hammer.
  3. Build a form for the concrete with two pieces of lumber cut to match the height of the curb. Use 2x lumber that is about 3 or 4 feet longer than the opening. Prop the boards in the opening, using concrete blocks or other heavy objects to hold them in place. For added security, you can temporarily bolt the boards to the existing curb or nail several small boards across the tops. You will be pouring concrete between these big boards and you want to make sure they don’t move when you do.
  4. Make sure that you have enough concrete on hand before you begin. Calculate the cubic feet you will need, then buy as many bags as necessary. Mix bags of ready-mix concrete with water in a wheelbarrow or large tub. Shovel concrete into the form. Add small amounts at a time and try to avoid hitting the boards. Once the form is filled, use a mortar trowel to smooth the tops.
  5. While the concrete is still wet, insert 1/2-inch anchor bolts in the center spaced no more than 6 feet apart and 12 inches from each end. Plan ahead so that you don’t set anchor bolts where wall studs will be located. Let the concrete cure for three or four days before removing the form boards.
  6. Most garage floors slope toward the door or a drain. You can level the floor if necessary using a self-leveling concrete or gypsum-concrete mixture. Check with your supplier or the manufacturer to make sure you choose a product suitable for the depth you require. If you are not extending the curb, check with a construction professional before trying to level the floor. Follow the manufacturer’s instructions carefully. These compounds seek their own level, so you only need to mix and pour them. Wait at least two days before walking on the surface and a week or more before installing any floor covering.

A Dozen Reasons Why You Need A New Garage Door

1. New garage doors can increase the value of your home.
An online survey says that 71% of homeowners who recently replaced their garage door believe it increased the value of their home. When nationwide real estate agents were shown “before” and “after” photos of houses upgraded with new, stylish garage doors, they increased the list price of the home anywhere from 1 to 4 percent. That means a $2,000+ investment in a garage door could increase the sale value of your home by as much as $7,000 if you’re selling a $175,000 home.

2. New garage doors can put money back in your pocket.
The Federal Government’s Energy Improvement and Extension Act of 2008 extends tax credits for energy efficient home improvements. This includes qualifying insulated garage doors. That means that adding a new garage door in 2009 can save you money by helping to lower home energy consumption and costs AN D it will help pay for itself this year through the tax credit incentive, worth up to $500.

3. New garage doors help you Lower The Door On Crime.
According to statistics compiled by metropolitan police departments, approximately 50 percent of all residential burglaries can be traced to an open or an unsecured garage door. How many times have you gone in your house after working in your yard or carrying groceries out of your car and left the garage door open? The garage door industry suggests that you Lower the Door on Crime in 2009 by making it a practice to always close and secure your garage door to protect the valuables in both your home and your garage.

If you’re looking for helpful security devices to remind you to close your door, you can purchase an open garage door indicator that can be affixed to your door. When a garage door is left open, a warning light will indicate “open door.” Homeowners can sleep easy, knowing their garage doors are closed and their families are safe.

4. New garage door openers have built-in safety features.
Photoelectric eyes – mounted about six inches above the floor – cast an invisible beam across the door opening and provide extra protection against entrapment. If a door is closing and a child or pet runs underneath the door, the beam breaks, causing the door to automatically reverse.

5. New garage doors can work even during power outages.
A popular accessory sold with new garage door openers is a battery back-up system that allows you to use your opener several times, even after the loss of power to your home. It’s a wonderful feature that prevents you from being trapped outside in a storm.

6. New garage doors are today’s front door.
A nationwide survey of consumers said that 71 percent of homeowners use their garage door openers to get into their homes every day, even more often than the front entry door. The key to the front door is now the garage door’s remote control and keypad. Yesterday’s latchkey kids are today’s keypad kids.

7. New garage doors can help you keep your house clean.
With a keyless entry pad mounted outside your garage door, why traipse dirt in through the front door when you can enter through the garage? You can leave muddy shoes or boots and drenched coats in the garage and keep your house cleaner.

8. New garage doors can be a fashion statement.
People are becoming more style conscious when replacing their garage door. On many American homes, the garage door claims a third of the façade, so it’s a snap to quickly makeover the look of your whole house. You can easily increase curb appeal when you choose from hundreds of different looks in elegant and stylish carriage house, contemporary or raised panel doors.

9. New garage doors can express your individuality.
Housing developments have their advantages, but individuality usually isn’t one of them. In homes that are more than five years old, chances are your door is a solid-colored, raised-panel door that looks like every other garage door. Choose a fashionable contemporary or carriage house garage door, and your house instantly stands out from the crowd.

10. New garage doors can protect your family from powerful winds.
Reinforced garage doors are now available to help your home stand up to brutal winds. Researchers studying the wind effects of devastating storms know that garage doors are often the entry point for severe damage. A new strong garage door is an integral part of maintaining the structural integrity of your home.

11. New garage doors can help accessorize your life.
Garage door opener accessories abound. Many new garage door openers switch on lights in your home as you’re pulling up the driveway. Some alert you if you left the garage door open. Some door openers are activated only by your fingerprint. You can even make a fashion statement with your garage door remote by customizing it to match your car’s interior.

12. New garage doors should be installed by a professional.
Don’t try to install the door yourself. It’s a complex and dangerous task. Garage door springs are under extreme pressure and, if not handled properly, can release with enough power to seriously harm or kill someone. Specific tools and training are needed; therefore, it’s highly recommended that you have a professional who can do the job in just a few hours and haul the old door away. The cost of installation is well worth it. Find a professional near you at’s “Your Local Garage Door Professionals” page.