An insulated garage will stay cooler in the summer and warmer in the winter. The first step is to be sure the attic is well ventilated. Check to see how many attic and roof vents you have. A good rule of thumb is a total of 1 sq. ft. (144 sq. in.) of vent opening per 300 sq. ft. of attic divided between the soffit and roof vents. For a typical 20 x 22-ft. garage, you’d need about six 4-in. x 12-in. soffit vents and two standard square roof vents. Make sure your ventilation is effective by installing vent chutes between the trusses. Vent chutes have a channel that prevents blown insulation from blocking the airflow from the soffit vents to the attic space. Plug the area under the vent with wood blocking or plastic and a chunk of fiberglass insulation to prevent wind from blowing up through the insulation or insulation from filling the soffit.
Leaky doors and windows let in uncomfortable drafts and increase heating and cooling costs. Check your garage service door to be sure it has good weather stripping and a threshold that seals tightly to the bottom of the door. In most cases, if your service door is missing a threshold and weather stripping, it’s more efficient to replace the door with a new, weather-tight version. You can buy an inexpensive prehung metal exterior door at home centers and lumberyards.
While some homeowners fully transform their garages, others simply want to install a new garage door. Luckily, replacing a garage door is a rather simple project, for a trained professional. The reason we say trained professional is due to the garage door spring. These springs are wound up very tight and one small mistake can turn into a serious injury. Therefore, play it safe and contact a garage pro whenever you’re installing or replacing your garage door.
Before you install the drywall, temporarily remove the brackets that support the garage door tracks and opener. This will make it easier to install the 4-mil poly and ceiling drywall and will result in a neater-looking job. Start by carefully measuring and recording the position of the tracks and opener. Measure from the nearest wall and from the floor. Then close the garage door, lock it closed and unplug the opener to disable it. Unscrew or unbolt the brackets that support the garage door tracks and remove them. Also remove the garage door opener brackets and support the opener on a ladder. It may be easier to entirely disconnect the opener and set it aside. Reinstall the garage door track brackets using a new section of angle iron on the ceiling. Attach each new ceiling angle iron with four 5/16-in. x 3-in. lag screws driven into the center of the ceiling joist or into wood blocking that’s screwed to the adjacent ceiling framing.
Heating & AC ($1000-$5000): Adding central heat and air into your garage can either be simple or difficult. If you have a robust heating and air conditioning system in place it is as simple as expanding your existing ducting. If the additional square footage is more than your system can handle you will need to add in a new unit. Luckily, a small garage usually is able to be fit into your existing system.
And you really need your investments protected, but you just don’t have the funds to build some of these other options. Well, don’t give up hope. This video shows you how to build a pretty decent structure that will do what you need it to do for basically no money. And honestly, if you have the materials on hand it could actually be built for free.