As cold weather begins to set in, many people retreat to their garage to escape the chill. As do vehicles, so drivers hope to avoid scraping off ice and snow in the morning. If there’s any space remaining, ongoing projects are moved in with hopes of finishing them soon or carrying them over until spring.

Closing up the doors and windows, many start using supplemental heat to make their garage, shop or shed even more hospitable. Propane tanks are filled. Pilot lights are ignited. Space heaters are plugged in.

Then, without much thought, thermostats are turned up to drive away the chill. Unless folks remember how to manage this extra use of energy, they may be shocked when their first winter utility bills arrive or the fuel tank out back is empty before expected.

Usually the garage, shop or shed is the least energy efficient space at a residence. A typical two-car garage measures 480 square feet, or about 20 percent of the size of the average U.S. home. It is often the least insulated and uses the least efficient heating systems. Yet, some are taken back in the middle of winter when keeping these areas at 50°F or higher increases their heating costs by 50% or more. Before taking up refuge in your garage this winter and cranking up the heat, consider a few of the following opportunities to keep your energy use from literally going through the roof.

Insulate the walls

While most people insulate their garage attics before heating them, many older homes (and even some newer ones) were not built with insulation in the walls of the garage. While most have outside siding, sheathing and a layer of particle board to keep elements out, these materials do little to retain heat.

Insulating can be as easy as tacking fiberglass insulation between exposed joists. If your garage walls are finished, insulation can be blown in through a small hole in the drywall or paneling.

Caulk between the walls and the concrete floor

Most garages were not built using compressible foam between the lower framing and concrete floor. Over time, the framing can swell, shrink and move, leaving gaps which will allow air from the outside to leak in. You can either use a foam sealant or a latex/silicone-based caulk to seal this often-overlooked area.

Seal the door between the house and garage

If your garage is attached to the house, the door leading into the home is often a major source of cold air leaking into the conditioned area. If your garage is detached, the passenger door may be letting much of your garage heat escape. Check to ensure weather-stripping is installed around the entire door frame, and that it’s intact, pliable and provides a snug seal. Also, ensure your threshold and door sweep are sealing at the bottom.

Insulate the garage door

Even if your garage has properly-insulated walls, you may have uninsulated garage door(s). This negates much of the benefit from insulated walls. A new, insulated door will cost several hundreds of dollars or more, but will provide a clean appearance. A lower cost solution is to purchase foam board insulation and install it on the inside panels of your existing doors. Remember, you must cut the foam board to a size a little smaller than your garage door’s panels so the insulation doesn’t smash together as the door rolls up and down.

Switch to LED lighting

Compared to traditional, incandescent lights, LEDs use only 10 percent of the electricity to produce identical illumination levels. Compared to fluorescent lighting, LEDs use 40 to 60 percent less energy for the same amount of light. More importantly, fluorescent lights produce less and less light as the temperature drops. Many fluorescent lights will not even operate below 10°F. In contrast, LEDs slightly increase their light output the colder it becomes.