Air Intake To The Attic

Nfa is the unobstructed area through which air can pass through a vent usually measured in square inches.

Air intake to the attic.

Attic square footage 2 square inches of exhaust and square inches of intake net free area nfa needed. Grab a flashlight and inspect your attic during the winter. Similar to the static method adequate amounts of intake air into the attic space should be provided. Intake vents located at the lowest part of the roof under the eaves allow cool air to enter the attic.

The first and possibly most important thing is to make a commitment to yourself to change your hvac filters regularly. Having your hvac system in your attic isn t dire though you ll need to do some work to keep your air conditioner or furnace system running as efficiently as possible. Hot air exhaust vents located at the peak of the roof allow hot air to escape. Warm air that escapes rooms below gets trapped in the attic.

This return air intake grille typically includes some type of filter to keep dust and debris out while allowing air to pass through. 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. See figure 2. Fresh air intakes are a key component the hvac system utilizes to maintain a safe and comfortable indoor environment in your home.

Ventilation manufacturers assign an nfa value to the non motorized vents they make. We are going to discuss what a fresh air intake is and how a properly installed fresh air intake can increase your unit s efficiency performance and prolong the life of your furnace. We will also cover how fresh air intakes play a vital role in determining your. 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.

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 indoor portion of your unit has an air conditioner return air intake usually located on the ceiling. Attic ventilation works on the principle that heated air naturally rises primarily utilizing two types of vents. The air passes through the filter of the unit and quickly passes over the supercooled coils inside.

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.