Air Intake To The Attic

According to the national roofing contractors association nrca a power vent with an airflow rate of 1 0 cubic foot per minute per square foot of attic space measured at the attic floor is generally considered to be equivalent to a 1 150 ventilation ratio.

Air intake to the attic.

Intake vents located at the lowest part of the roof under the eaves allow cool air to enter the attic. See figure 2. Hot air exhaust vents located at the peak of the roof allow hot air to escape. Nfa is the unobstructed area through which air can pass through a vent usually measured in square inches.

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. Fresh air intakes are a key component the hvac system utilizes to maintain a safe and comfortable indoor environment in your home. Unlike passive ventilation where air flow must travel from the lowest point in the attic to the highest powered ventilation uses air intake from all areas of the attic both high and low. This return air intake grille typically includes some type of filter to keep dust and debris out while allowing air to pass through.

We will also cover how fresh air intakes play a vital role in determining your. Attic square footage 2 square inches of exhaust and square inches of intake net free area nfa needed. When using any type of powered ventilation product for an attic application all passive attic vents will become sources for air intake. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents.

Warm air that escapes living space also carries moisture that will condense on rafters or roof sheathing. Proper attic ventilation consists of a balance between air intake at your eaves soffits or fascias and air exhaust at or near your roof ridge. The first and possibly most important thing is to make a commitment to yourself to change your hvac filters regularly. The indoor portion of your unit has an air conditioner return air intake usually located on the ceiling.

Ventilation manufacturers assign an nfa value to the non motorized vents they make. Similar to the static method adequate amounts of intake air into the attic space should be provided. The air passes through the filter of the unit and quickly passes over the supercooled coils inside. Grab a flashlight and inspect your attic during the winter.

Warm air that escapes rooms below gets trapped in the attic.