We are about to have a new roof installed and have a question about venting our attic. We currently have a ridge vent and a power exhaust fan on the roof. Our roofing contractor says it is not good to have both and recommends eliminating the ridge vent. Do you agree with this advice, and if not, what do you recommend for attic ventilation? –Jerry
Attic ventilation for the majority of homes is marginally adequate, a fact that can be verified by entering most attics on a hot summer day. Lack of sufficient attic vents can increase heat gain in a home, driving up the cost of operating an air conditioner and shortening the useful life of composition roofing materials.
Industry studies of attic ventilation, published in the Journal of Light Construction, have shown that the best type of ventilation is soffit and ridge venting. This involves the natural process of convection, the tendency for heated air to rise. In this case, hot air in the attic rises through the ridge vents and is replaced by cooler outside air that is drawn into the eave vents. The warmer the attic air becomes, the more quickly it vents outward and is replaced.
In these same studies, it was found that power fans provide the least effective ventilation, no matter where the fans are placed. This is because of “dead zones” — areas of an attic where air movement is not affected by power fans.
Another effective means of convection venting involves the use of air turbines — those round spinning devices commonly seen on the roofs of commercial and manufacturing buildings. When these turbines are equipped with good roller bearings, they can outperform power vents.
Before buying my home, I hired a home inspector. He said something was wrong with the heating and air conditioning system and recommended review by an HVAC contractor. The seller had his home warranty company check the system and they left a receipt saying that it was in working condition. But shortly after moving in, the system stopped working. The warranty company came out again and said that the problem is not covered because it is a pre-existing condition. How can they say that when they found it to be OK just a few months ago? How can I get them to honor this claim? –Lorena
If the warranty company inspected the HVAC system and certified it as operative, then they cannot justifiably claim that the current problem is pre-existing. Hopefully, you kept a copy of the receipt that declared the system to be functional. If they refuse to take responsibility for their previous finding, you should file a complaint with the state agency that regulates insurance companies. If the state regulatory agency is too slow or shows insufficient interest, you can file a suit in small claims court against the seller and the warranty company.
To write to Barry Stone, please visit him on the Web at www.housedetective.com.