How To Protect Your Garage From Extreme Temperatures

Install a unit heater in the garage. Insulation and weatherstripping effectively guard your garage from extreme winter weather; but if you’d like to be extraordinarily toasty, you can add a unit heater. (On the other hand, if you have only mild winters, then rather than insulation or weatherstripping, an electric unit heater is probably all you’ll need, since you’ll want heat only once in awhile.) This is a great way to heat your garage with nominal cost and space requirements. Gas-fired units are generally cheaper to operate overall, but they’re more difficult to install since they require exhaust venting and a gas supply. An electric model, is easier to install, but more expensive to operate. A good electric choice is the mini-split heat pump, which provides remarkably efficient heating and cooling for your garage with only a 3" hole through an exterior wall.

Hot Weather Protection

In the summer months, the main goal is to increase the airflow in your garage. The following measures are worth considering:

Wall insulation keeps out summer heat economically. Use wallboard or other paneling to encapsulate the material. You’ll prevent teenagers, toddlers, and pets from tearing things out.

Leave the garage door slightly open, about a foot from the ground, and add a fan.

Attach an adjustable rollaway awning onto the sunny side of the garage. You’ll be creating shade to cool things off.

Insulate the garage ceiling. If you use paper-backed batt insulation, ceiling wallboard isn’t required. Install the insulation using staples, paper side down, or keep the insulation in place with netting. You can also use staples to fasten the netting. Experts advise that you do both.

Plant a tree nearby. A hardwood or deciduous tree is an affordable and aesthetic way to cool your garage in summer. (It will even keep the garage warm in winter.) Plant the tree between the garage and the position the sun takes during the hottest part of the day. The tree’s leaves will provide welcome shade. (In winter, the bare branches will let sunlight through to provide warmth.)

Install a stationary vent on the roof. This is an inexpensive way to make an exit point for hot air trapped in the garage attic. Or, if you can spend more, install a mechanical exhaust system, in which fans will draw cooler air from the garage into the attic. This will cool the attic and also the space below.

Insulate the garage overhead door. For a metal garage door, add a layer of rigid insulation 2" thick, attached to the inside of each panel using contact cement. Or, an insulated sectional overhead door is an ideal alternative.