About Your Kitchen Exhaust Hood
Most kitchens I encounter on home inspections in San Diego and Temecula Valley have a range hood of one type or another installed. Some are integrated into a combination microwave/hood, and some are stand-alone exhaust hoods.
Types of Exhaust Hoods
Many exhaust hoods merely recirculate the air by pulling it through the filter and then just blowingit back into the room. I don’t know how this can possibly remove the odors and moisture created by the cooking process.
For the exhaust hood to be truly effective, it needs to exhaust this dirty air to the exterior of the home. If the hood is on an exterior wall, the exhaust duct can be installed to go through the sidewall. This makes for a very short run of ducting. If the hood is installed on and interior wall, then the duct can be installed to exhaust the dirty air through the roof. It can also be run through a soffit to the exterior wall. The route you take should be discussed with your HVAC contractor. He will give you multiple options and the cost involved for each option.
Use The Proper Duct Material
Most manufacturers recommend using a smooth rigid 6” duct for your exhaust. Flexible, or corrugated duct, is not approved for use by any manufacturer that I am aware of. The use of a flexible duct is just inviting a fire hazard from a build-up of grease and dirt.
When installing the duct the joints should be sealed with the appropriate foil tape. Cloth backed duct tape is not recommended for exhaust ducts and in attic spaces. The heat associated with these areas causes the duct tape to lose its adhesive capabilities.
Who Should Install Your Exhaust Hood?
The installation of an exhaust hood can be done by a handy homeowner with help from YouTube and other online resources, however, I recommend that you use a licensed professional so that you know it is done correctly.