Most homeowners are merely throwing away money with their heating and air conditioning systems. A lot of heat transfers through the home’s thermal envelope. Secure the envelope with energy efficient insulation, doors and windows, and the home owner can expect to save big on energy bills. There is also the possibility in 2009 and 2010 to recoup much of the cost of weatherization through Energy tax credits at federal, and sometimes state and local levels.
The envelope of the house is designed to keep heat in during cold winter weather, and heat out during summer. The floor, walls, ceiling, roof, doors and windows provide the critical barrier to the transfer of heat.
The thermal envelope is the pocket of protection around the living area. It is designed to protect in much the way that outer wear protects the body from cold, ice and snow in the winter. Just as unprotected skin will freeze in a matter of minutes during cold winter months, so too a house with gaps in the protective barrier will leak energy and make the home both uncomfortable and costly in terms of energy bills.
Insulation is a major factor in home energy efficiency and in protecting the living area from loss of energy. Most contractors will only put in as much insulation as is required by local building codes and rarely does this meet current federal guidelines for energy efficiency.
Insulation is evaluated by R value, a method of determining the heat transfer resistance of the insulation. What is now recommended, and required in order to obtain energy tax credits for adding insulation during a home improvement, is to have ceiling R values at between R-30 and R-60, wall insulation at R-25 to R-49 and floor insulation at R-13 to R-30. Check out the Energy Star insulation value chart for more details.
Upgrade the insulation R value in your home and experience a dramatic improvement in comfort and savings. Energy cheap online flomax Star estimates are up to a 20% reduction in heating and cooling costs when insulation is upgraded.
Another major cause of energy loss is the windows and doors. It is estimated that the windows account for as much as a 25% loss of energy. The framing around doors is another major spot for energy loss. Doors should be flush to the frames and include seal pads on the inside of the doorstops.
As of June 1, 2009 the rules for claiming the federal energy tax credits changed when it comes to windows put into service after that date. Instead of just meeting Energy Star standards windows, doors and skylights must now have a U-factor (the measure of how well heat loss is prevented) of less than .30. The Solar Heat Gain Coefficient (SHGC–the measure of how well heat from sunlight is blocked) must also be less than .30. These are the standards of the International Energy Code Council (IECC) as well.
So upgrading the thermal envelope around the home can save energy, thus reducing the use of non-renewable fuels. It has the benefit of saving the homeowner $100 or more per month on energy bills. It offers the possibility of giving the homeowner up to $1500 back in energy tax credits. Last, but not least, the family will stay warmer in winter and cooler in the summer with a more even temperature throughout.






