Heat rises, and during the summer this can create some significant issues for your attic. Even if your attic is only used for extra storage space, the temperature can rise to a whopping 150 degrees fahrenheit during hot summer days! Not only will this put extra strain on your air conditioning and probably lead to an expensive ac repair in your future, the additional heat in your attic can bake asphalt shingles on the roof and cause damage. Your attic can also retain moisture if it’s not ventilated well, causing the wood to warp, mold, or rot.
While there are numerous ways to cool down your attic during the hot months of the year, including additional air conditioning or electric ventilators and fans, you can easily create a passive ventilation system that will help circulate air on its own and provide an escape for the heat as it rises. By installing a system of ridge and soffit vents, which work to bring in cooler air and push out hotter air as it rises, you can keep your attic from reaching such high temperatures without having to pay a fortune each month on electric options. Be sure to follow any building regulations for your home, and consult a roofing professional if you don’t feel comfortable on your roof (especially if you have a fear of heights!).
DIY Attic Ventilation System Installation
The first step in addressing attic ventilation is to determine how much venting area you’ll need to divide between the ridge and soffit vents. Divide the square footage of your attic by 150 to determine your net free ventilating area (NFVA) in square feet; multiply by 144 if the vents you’re buying use square inches. At least 50% and up to 80% of the NFVA should be provided by the ridge vent.
Installing a Ridge Vent
- Begin by removing all cap shingles. Use a utility knife to cut through the shingles ¾ - 1 ¾ inches from the ridge, stopping 6 inches before the end wall on each side.
- Use a power saw to cut through the wood sheathing and create a slot opening at the ridge, but pay attention to your blade depth; you don’t want to cut through the roof trusses or (if there is one) the ridge board. Depth should be about ¾ - 1 inch.
- Insert the end plug into the first section of ridge vent. If you are using metal vents, connect the proper amount of sections with the provided connectors.
- Center and align the ridge vent flush with the end of the house. If you are using a metal ridge vent, align the vent over the slot in the roof. Then fasten the vent with 2 inch roof nails. If you are using a shingle-over ridge vent, pre-fasten the first section before adding additional sections. Be sure to insert an end plug.
- For metal ridge vents, place straps over the joints and fasten with the roof nails. If shingle-over, cut the cap shingles and fasten into place with the roof nails.
Installing Soffit Vents
- Soffit vents are installed in the eaves of your home, so begin by removing any insulation that will get in the way of installation. Choose the placement of the soffit vents that will be free of obstruction and mark these places.
- Get the soffit vents you plan to use. Cut a space for each vent in the eave slightly smaller than the size of the vent using your power saw to ensure a snug fit. You can mark the perimeter of your cut using small drill holes to better guide your saw. The piece of roof should fall out of the open space you’ve created.
- Fit the vent into the space and fasten, using the provided screws. Finish by adding caulk to the edges to prevent drafts, and allow the caulk to dry for a day or two.
- If insulation will prevent airflow between the soffit and ridge vents, you may have to insert baffles. Then, replace the insulation in your attic and enjoy the cooler temperatures, even during the hotter days of summer!