April 15, 2010
When someone says “Green” or “Energy Star” there are a lot of things that most people think. Many are not sure exactly what it all means but most want to lower their energy cost/usage. When someone refers to insulation most think of the traditional insulation methods of batt insulation or blown in insulation for your attic.
Batt insulation can be effective when installed correctly with proper caulking. A typical 2×4 wall can achieve an R-13 or R-15. Most attics are blown in to achieve an R-38 or R-50.
The most common energy efficient methods today would be a sprayed in foam insulation. There are a few options for this, the first being a Closed Cell Foam. This adds rigidity to a wall and ensures all gaps and crevices of walls including around outlets etc. are completely sealed. Closed Cell Foam is typically installed 3″ thick in a 2×4 wall achieving an R value of R-18.6. Open cell is also a popular method due to cost savings and will achieve an R value of R-12.6. Even with slightly less R value than a batt it still adds significant energy efficiency due to the sealing of all gap a creating an air tight home.
Another popular method is to add an inch of closed cell foam and then installing the balance of the cavity with blown in fiberglass insulation. This option provides the air-tight seal at a more reasonable cost.
Spray foam’s ability to create an air-tight seal for your home is the most important factor in creating an energy-efficient, comfortable, and healthy home.
Contact Modern Homes, Inc. for any questions or to have our specialist review what may be best for you.
January 11, 2010
Single paint windows are one of the largest source for heat loss in a home. They have low insulating value, high air leakage and can be responsible for 25 to 50 percent of the energy use to heat or cool a home.
Almost any windows will improve over single pain and new energy efficient glass/window options can even significantly increase the insulating value of dual pain glass.
An easy way to determine window efficiency would be to choose a window with an “Energy Star” label. They do have a National Fenestration Rating Council (NFRC) energy performance label on all windows that will help you compare energy rating on windows. There is five factor used.
* U-factor measures how well a product prevents heat from escaping.
* Solar heat gain coefficient (SHGC) measures how well a product blocks heat caused by sunlight.
* Visible transmittance measures how much light comes through a product.
* Air leakage measures how much air will pass through cracks in the window assembly.
* Condensation resistance measures the ability to resist the formation of condensation on the interior surface.
The optimal combination of U-factor and SHGC depends on the climate zone as well as direction.location of your home. Products with the Energy Star label will include a map to help you determine the right window for your area.
There are a variation of different glass types that can be chosen. Low E Glass is typically the standard in efficiency glass. A Low-E coating is a microscopically thin, virtually invisible, metal or metallic oxide layer deposited directly on the surface of one or more of the panes of glass. There are also argon gas than can be filled in the window to help efficiency as well as Super Spacer® solid silicone foam spacer to help reduce heat transfer. There are also Laminated Glass and Sun coatings that are available dependent on the windows manufacturer.