Vent the roof deck. If the attic space is going to be conditioned, either for living or mechanical purposes, or if a home design calls for a vaulted ceiling, provision R806.3 in the International Residential Code calls for the roof deck above the space to …

Oct 12, 2023 · A hip vent should be installed in the upper part of the hip, according to GAF. For roofs that run into walls, Cor-A-Vent developed the Roof-2-Wall vent that fits over a slot cut in the roof sheathing just below the roof-wall intersection. The rafter bays that normally would simply stop at the wall line now have a way of exhausting air.

Roof Vent Retrofit from the Outside In Reroofing is the perfect time to lift the hood and make short work ...

Then they nail it along the edge every 6 to 10 inches. When ridge vent installation is performed correctly, the vent increases the home’s energy efficiency and extends the life of the roof. The next step is to cap the ridge. The ridge cap used on this roof comes in 3-ft. shingles which are perforated to be broken into 12-in. squares.

A quick note on the depth of the vent baffles: The IRC calls for a minimum ventilation space of 1 in., though building scientists suggest leaving a 2-in. vent space for better airflow. Since the distance between the roof sheathing and top plate on this and most other low-pitch roofs is cramped, a deep vent channel reduces the space for insulation.

Back up roof vent boots with flashing, counterflashing, and proper shingling to prevent leaks. By Mike Guertin Issue 276 - July 2018 Synopsis: Mike Guertin describes his method for flashing roof vent boots, a main source of roof leaks.

Jan 6, 2016 · Ridge-vent NFVA ranges from 14 sq. in. to 18 sq. in. per lin. ft. (Check manufacturers’ instructions for the ratings of specific products.) If 46 ft. of ridge vent (often it does not extend to the ends) is installed and the product has an NFVA of 15 sq. in. per lin. ft., we can take 46 ft. and multiply it by 15 sq. in., which equals 690 sq ...

To reduce chances that vent gases will enter the home, stack tops must be at least 6 in. above the upslope side of the roof and at least 3 ft. above any part of a skylight or window that can be opened. A vent stack must be at least 12 in. horizontally from a …

Better vent baffles. Site-built vent baffles can be sturdier and more airtight, and can provide deeper vent channels, than manufactured baffles. Baffles of vapor-impermeable materials like foil-faced polyiso aren’t necessarily problematic if you pay attention to air-sealing, as more moisture moves through leakage than by diffusion.

Installing a prefabricated vent baffle (above) is certainly the fastest and perhaps the most cost-effective way to create a vent channel: Staple prefab baffles between rafters and use canned spray foam to air-seal baffle edges. Insulating under the roof is the conventional way to go and probably the most affordable if the roof is in good shape.