You can also contact your local municipality to check on building code in your area.
Roof ventilation requirements.
The majority of the requirements related to attic ventilation have not changed much from the previous editions.
Feet of attic space divided 50 50 between the inlets and outlets.
Roof vents choose one of the following products to meet the recommended exhaust nfva of 528 square inches.
Measure the length and width of the attic floor space to be ventilated.
Foot of ventilation for every 150 sq.
Attic ventilation requirements how many attic vents your roof needs industry standard for proper attic ventilation recommends for no vapor retarder type of attic insulation no paper plastic or aluminum layer between the attic floor and insulation layer 1 sq.
R806 1 ventilation required enclosed attics and enclosed rafter spaces formed where ceilings are applied directly to the underside of roof rafters shall have cross ventilation for each separate space by ventilating openings protected against the entrance of rain or snow.
Ventilation of attic spaces is required by most building codes as well as by roofing material manufacturers and the national roofing contractors association nrca.
Most building codes require a ratio of 1 150 ventilation space to attic floor space.