from Kevin in Waunakee, WI:
#449
How can I make the ceilings in our 1970s built home with vaulted ceilings and 8" joists more energy efficient? eE burn wood so changing the whole roof to attic & adding insulation would not save enough to pay for itself.
One effective retrofit would be to install rigid foam board.
One effective retrofit would be to install rigid foam board (R-values range from 4 to 7 per inch) on the underside of the existing ceiling to increase the insulation (R-value). How many inches you could add would be limited by the amount of reduction in ceiling height you are willing to relinquish. You would also need to cover the rigid foam with a noncombustible (fire -rated) material such as sheetrock. An added benefit would be reduced air leakage through the existing ceiling penetrations. There are, of course, other details/considerations that would have to be dealt with when installing foam board to an existing ceiling plane. In some cases, rewiring of fixtures (lighting, ceiling fans, etc.) may be necessary to accommodate the additional insulation.
Because I have not seen the configuration of your (scissors trussed?) vaulted ceiling, it is difficult to comment on the possibility of adding more (blown-in) insulation to the existing insulation (from the attic side or through the roof). One way to determine this possibility would be to engage the services of a Home Performance with ENERGY STAR® consultant. They will conduct a thorough inspection of your home and identify opportunities to improve your energy efficiency and lower energy costs. You'll receive a written report of the findings and a list of recommended solutions. That way you can compare the potential savings, cost and Cash-Back Rewards associated with each of the recommendations.
Published Wednesday, September 02, 2009