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Is your mechanical closet inside or outside the heated space of your house? Many mechanical rooms are half-in, half-out and present a major source of heat loss. There should be a continuous, insulated and airtight barrier between all heated and unheated spaces.

Check the walls of the closet for insulation. Look for fresh air grills that may be connected to the crawl space or attic. If the closet is outside the heated space, ensure the water pipe, water tank and ductwork are insulated.

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Hot water

Washer & dryer

  • Switch to an energy-efficient clothes washer, many of which are front-loading. Front-loading machines save water and energy, are easier on your clothes, use less detergent, and allow your clothes to dry faster. Look for the ENERGY STAR label. New ENERGY STAR dryers spin clothes instead of relying on the dryer to heat the water out. CEE Tier 2 and Tier 3 provide additional performance advantages.
  • Vent dryers to the outside. Choose a metal duct, preferably with a smooth interior, and use the shortest, most direct route possible to vent it to the outdoors. Secure the vent with metal tape only and/or mastic only; screws will snag lint and accelerate build up. For the same reason, remove any metal screen at the vent termination. Check to see there is a damper that closes to prevent cold air infiltration and insect entry when the dryer is not in use.
  • Check the inside of the duct twice a year (or as needed) for accumulated lint and to ensure that it has not come loose in the wall cavity, attic or crawl space. Lint build-up presents a fire hazard and could result in overheating and a shortened lifespan of the dryer. Failed vents also add moisture indoors or in crawl spaces and could foster mold growth. Gas heated dryers would also add carbon monoxide and other dangerous combustion gases into the home.
  • Use hot or warm water only for greasy clothes and diapers. Detergents now work effectively with cold water for both wash and rinse cycles. Stick with liquid—instead of powder—detergents, which may cake up in colder water.
  • Seek alternatives to having a dryer vent with an indoor bypass, allowing dryer air into the house to capture the dryer heat. Such a system is dangerous because it adds moisture, fabric softener, and (in the case of gas dryers) combustion products to indoor air.

Heating & cooling

  • Install the furnace or boiler in a central, well-insulated mechanical closet to save energy by reducing delivery distance and heat loss.
  • Locate your heating and cooling system inside conditioned space to take advantage of indoor temperatures; however if the furnace burns oil, gas or propane, it may be prudent to keep the heating system outside the conditioned space. This will further prevent spillage of exhaust gases into indoor air.
  • View more Eco-Cool Remodel energy resources



Utility room flooring

Additional resources

Heating and electrical systems

Energy savings

Washing machines and dryers


Related information

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