Attic Air Ventilation Requirements

It is important that air movement occurs and is not impeded by any framing members of the.

Attic air ventilation requirements.

To lower attic temperatures and to remove excess moisture. Allows cool dry air to enter the attic. This article will cover why you need ventilation the most common type of ventilation the building code requirements and common ventilation related issues. Vents are rated by their net free area or the amount of space for air to flow in or out.

So how much of that air circulating through your attic you really need you can find online calculators to give you the explanation in numbers and i ll try to add a few words to it. In of vent opening per 150 sq. Attic ventilation serves two main functions. Prior to installing the ridge vent a 1 inch wide strip of roof decking is cut out along both sides of the ridgeline to allow for air movement through the vent.

Attic ventilation requirements air circulation. The following product options will allow you to achieve an intake nfva of 528 square inches. This means that if you have a 1500 sq attic then you would need at least 10 sf of ventilation. Attic ventilation is an important part of keeping your building healthy.

Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation evenly split between intake and exhaust for every 300 square feet of attic floor space. A ridge vent is a ventilation strip that is placed along the ridgeline of the home. You can calculate attic ventilation requirements by determining the square footage of your attic floor its width times its length and compare that to the total required net free area nfa. If not measure the size yourself.

Attic fans are intended to cool hot attics by drawing in cooler outside air from attic vents soffit and gable and pushing hot air to the outside. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. The open area of a vent is sometimes listed on the roof air vent as nfva net free vent area. Lowering the temperature in the attic can help reduce air.

Choose one of the following products to meet the recommended intake nfva of 528 square inches. Then aim for about 1 sq. Current regulations state that the minimum attic ventilation requirements are 150 1. The building code lets you reduce that by half under some conditions but more roof ventilation is usually better.