Energy and Comfort

Energy and Comfort: Working with your Design Professional for a Comfortable and Efficient Space

© Rob Gomez Photography

Thermal comfort is in your home is achieved by more than just adjusting the temperature on the thermostat. Shade Trees and Deep overhangs can contribute to your comfort in a warm, sunny climate. What other considerations should you keep in mind when designing for energy and comfort?

Recall from high school Physics class that heat is transferred in three ways: Radiant, Convection and Conduction. You can address radiant heat with shading and overhangs and with a well-designed roof. When replacing your roof, carefully consider the placement of a radiant barrier. Radiant barriers are now required by code for attics under new non-metal roofs and attics without insulation in the rafters. A radiant barrier acts like a foil tent on your peach pie, keeping the crust from burning in the oven. In this case, a radiant barrier in your roof helps to keep the heat of the sun out of your attic. Keep in mind that there are two important factors to consider for the radiant barrier to work correctly. First, it must have air flow around it. Installing insulation right up against the foil side of the barrier will completely negate its effectiveness. At least one inch of air gap will allow the barrier to reflect the heat away from the home. Second, the foil face must be kept clean. A dirty face no longer reflects heat. As counter intuitive as it may seem, the foil face in your roof’s radiant barrier should be shiny side down, otherwise you won’t see any benefit.

© Rob Gomez Photography

You can reduce heat gain via conduction by making sure your roof and wall insulation values meet or exceed code. When remodeling your home, improving attic insulation is the easiest way to achieve this. Talk to your HVAC engineer and/or Contractor for the best way to improve attic insulation, as the type and installation location of the insulation will need to coordinate your HVAC system and attic ventilation methods.

When considering your HVAC system, it’s important to know that your comfort in a room is determined not only by the temperature of the air around you but also by air movement (convection), humidity, and the temperature of the objects around you which can radiate or absorb heat. For example, I love tile floors because the cool surface helps to keep my house comfortable in the hot summer months by cooling my feet. Likewise, poorly sealed and insulated windows leak humid air in the summer and allow cold drafts in the winter. Replacing old windows with double pane and low-e glass can greatly improve the thermal comfort in your home by reducing the amount of humid, unfiltered and unconditioned air that is allowed to enter.

Keeping household humidity in check will often have a great impact on your comfort and therefore your electricity bill. In Central Texas, a significant portion of our air conditioners’ running time is due to excess humidity in the air rather than uncomfortable ambient temperatures. Consider adding a dehumidifier to your AC system. These will stretch out the range of comfortable temperatures before your fans or AC need to kick on.

Before you start construction, your design professional should be able to provide you with a RESCheck, which verifies that your new design meets energy code requirements for wall and window insulation values. A pre-construction meeting with your contractor and their team will make sure the whole team is on board with your plans for a more sustainable remodel.