Detached Garage? What You Need to Know About Heating an Exterior Space

November 23, 2021

Should you heat your detached garage — and if so, how can you keep this space warm without the ductwork or radiator lines that crisscross through the interior of your house? Most detached garages don't have access to a central HVAC system. But this doesn't mean this exterior area can't stay warm in the winter. Take a look at what you need to know about detached garages and your heating options.

Is It Really Necessary to Heat a Garage?

The answer to this question depends on several factors. According to the State Climatologist Office, the average fall temperature in Illinois is just over 54 degrees Fahrenheit and the winter temps fall to only 29 degrees. This means an unheated garage could stay at or under the freezing range for much of the fall and winter.

If you don't use your detached garage or store items that a cold climate won't affect (such as cotton clothing or soft children's toys), you may not need to heat the space. But if you keep your car in the garage, use it as an outside-of-the-house workshop, or store temperature-sensitive electronics, furniture, or anything made from wood or weather, this area needs some form of consistent heat. 

Why Isn't the Garage Part of the Home's Heating System?

From outdoor vehicle housing to work-from-home offices, garages have more than a few uses. Given the possibilities, why wouldn't this area come with a built-in heat source? The rest of your home has heating — but the detached garage isn't part of the system.

There are a few different types of common home heating systems. These include forced air furnaces, water-based/radiator boilers, and ductless heat pumps. Each type of home heating system requires some type of distribution method. A forced air furnace uses a series ducts to carry warm air through your home, pushing heat through vents in each room.

Unlike forced air systems, radiator/boiler heating uses hot water and steam. The hot water moves through pipes and into radiators (in each room). Like boiler/radiator systems, mini-split ductless heat pumps also won't require ductwork. But the indoor air handlers (which supply individual rooms or zones with heat) must connect to an outdoor unit.

The complex connections most residential heating systems require for delivery make it difficult to effectively heat an exterior or detached garage. While some garages have their own furnace or boiler, most don't connect to the ductwork or the radiator pipe lines in the main home structure.

This type of setup is costly, inconvenient, and would result in significant heat loss. The heat lost as the air or water traveled outside and then back inside (to the garage) again would drive down the system's efficiency and increase your utility bill.

Can You Heat a Garage?

Now you know why your home's HVAC system doesn't extend to the garage. But your detached garage needs heat to keep the car, your home office, items in storage, or anything else warm. What can you do to keep this space warm? 

It's possible to heat your garage separately from the rest of your home. This option is ideal for detached garages that can't or won't connect to the rest of the property's HVAC system. A qualified HVAC contractor can help you to choose a specialized natural gas or electric garage heater. 

This option won't require ductwork that extends from the rest of your home to the garage and doesn't rely on radiators. Instead, it's a self-contained system that a professional can mount on a wall or (in some garages) the ceiling area. These heaters are durable, low maintenance, and compact.

Do you need a heater to keep your detached garage warm in the Illinois fall or winter weather? Contact Service 1 Plumbing, Heating & A/C Inc. for more information.