Rosie on the Home: Do you might want to ventilate your attic? | Get Out
Arizona homeowners often call us to ask how to deal with the intense heat that can reign in their attics during the summer. Should you install more isolation effort? Should they put a fan in the attic?
When it comes to insulation, if your house is relatively new and has R-38 insulation in your attic, you probably don’t need additional roof insulation or radiation barriers, for example.
We also recommend homeowners not to install electricity fans. This is because an attic fan – regardless of whether the fan is solar-powered or electrically operated – only creates a negative pressure in the attic. This will pull the conditioned air into your attic from below in the rest of the house. That means your air conditioner is working harder than ever to cool down on the first floor.
Use vents to let the wind do the job
What you’ll want to install – if you haven’t already – is a system of passive vents that can reduce the heat in the attic using the natural force of the wind. Recently built houses have this type of system.
These types of vents can be installed later if necessary. We recommend making inlet openings on the roof edge or in the soffits under the gutter. Make sure the attic insulation doesn’t cover the vents or soffit openings. Otherwise, fresh air will not be able to get into your attic.
In areas of high negative pressure, place the exhaust vents high on the roof at or near the ridge. These ridge vents can create a continuous flow of air through the attic. You can also use louvers, covered openings on the gables that allow air to escape from the attic.
While power fans are a bad idea, you can install turbine vents – sometimes called whirlybirds – that turn “wheels” mounted near the ridge or roof edges. These devices can extract heat from the roof when the small blades of the turbines rotate when the wind blows.
Having adequate passive ventilation in your attic will extend the life of your roof and may also put a little less strain on your air conditioning system.
Some innovative builders also install vents while building houses with flat roofs. You install vents outdoors to protect any insulation that may be over your ceiling.
Be sensible about your attic
Homeowners should keep in mind that regardless of the temperature of your attic – 140, 150, or 160 degrees – the attic temperature will only be in the middle of summer when you are close to having R-30 or R-38 insulation over your ceiling raised Your cooling costs by around 10 percent. That means it’s 5 percent of your total electricity bill. For the average home in Arizona, that’s about $ 15 a month, and that’s only during the super-hot summer months.
For more do-it-yourself tips, visit rosieonthehouse.com. Rosie Romero has been an Arizona home builder and remodeler for 29 years. She is the presenter of the syndicated Rosie on Saturday morning on the house radio program, which can be heard from 8 to 11 a.m. on KNST-AM (790) in Tucson and from 9 to 11 a.m. on KGVY-AM (1080) and – FM (100.7) in Green Valley. Call 888-767-4348.