Get In Over Your Head! Tips for an Energy-Efficient Attic

The key to saving energy in your attic lies in two areas: insulation and ventilation. Increase your attic’s efficiency and reduce your energy costs with these two easy steps.

When thinking about energy-efficiency in the home, your attic may be the last place you think of – but it can be the most significant source of energy loss in most houses.

The key to saving energy in your attic lies in two areas: insulation and ventilation. During the winter, poor attic insulation causes more heat loss in your home than any other place in your house. During warmer seasons, lack of ventilation in your attic can cause excess heat to collect, causing energy costs to sky-rocket as well as creating moisture to build up, which greatly decreases the life of your insulation.

Increase your attic’s efficiency and reduce your energy costs in two easy steps:

Step 1: Audit

  • Check for air leaks. Most insulation does not completely prevent air leakage so before insulation, locate the areas that are releasing air. This can easily be done on your own by inspecting areas where differing materials come together (door and window frames, air vents, siding, foundation etc.) If you have more time, you can depressurize your house by closing all doors and windows, and turning off your air system while turning on all exhaust fans that blow air outside. Once you have done this, light an incense stick and pass it over places susceptible to air leaks. Where ever the smoke is pulled, an air leak may be present.
  • Check the ceiling for water stains. If your ceiling has water stains, that could indicate roof leaks or moisture build-up from poor ventilation.
  • Measure your current insulation. The Department of Energy recommends you have at least 11 inches of fiber glass or rock wool, or 8 inches of cellulose. Loose-fill insulation is made from fiber glass, rock wool, or cellulose while batt insulation is only made from fiber glass or rock wool. Although most houses are insulated with one of these materials, greener alternatives are available and often more efficient (see below).

Step 2: Take Action


  • Choose your insulation. Try a greener alternative to foam insulations that are petroleum based and made from non-renewable resources. A more eco-friendly choice is denim insulation. Denim insulation is made from 85% post-industrial fiber.
  • Cover your exhaust fan.  The Department of Energy recommends using a box to seal around the duct where it opens into the attic in order to decrease heat-loss.
  • Caulk the leaks. Make sure the areas around chimneys and framing are caulked with a high-temperature sealant. For smaller areas near the ceiling, use long-life caulk while the larger areas require expanding foam or rigid foam board insulation.
  • Insulate the entry. If entry to your attic is inside your home, make sure the access door is also properly air sealed and insulated.
  • Check your soffit vents. In order to ensure adequate ventilation throughout your attic, make sure you don’t block any soffit vents (which are vents from your attic to outside, under the overhang of your roof) with insulation.
  • Install a radiant barrier. Radiant barriers are an additional form of insulation that work by reducing the amount of radiant heat your roof collects from the sun. Not only is the barrier easy to install, it has the potential to lower your cooling costs by 5% and 10%. Radiant barriers can be either laid over your insulation or placed on the underside of your roof and come in foil or spray form.