Calculating Attic Volume

Measure the width of your attic in feet.

Calculating attic volume. Let owens corning roofing help you calculate exactly how much ventilation you will need for a healthy and balanced attic with our 4 step ventilation calculator. Calculate or enter the square footage of the attic or area to be vented. Attic square footage 2 square inches of exhaust and square inches of intake net free area nfa needed. Nfa is the unobstructed area through which air can pass through a vent usually measured in square inches.

Now let s figure out how much ventilation space we need. Whether you plan on improving the ventilation in your attic or adding energy saving insulation you will need to accurately determine its actual size. This calculator will help you estimate hip roof parameters including rafters and roof area person outline anton schedule 2011 08 29 17 53 20 one of users asked us to create calculator which will help him estimate hip roof parameters like rafter s lengths roof rise and roof area. Divide this number by two.

Then click on calculate. Make sure to measure in the center at the attic s highest point. Ok so now we know the square footage of the attic area to be ventilated. See how simple that was.

Input length width and desired r value of the area to be insulated. 1 500 square feet 300 5 square feet. Select if your roof is more flat of peaked. Next multiply the 4 square feet into cubic inches.

Enter the length and width of your attic or ceiling crawl space. Measure the height of your attic in feet. Then enter the height at the highest point. In our case the required 4 vents for the 1200 sq ft house multiply the 144 cubic inches by 4 576 cubic inches.

Remember the minimum area requirement when using a continuous system is a ratio of 1 300. Click the button to calculate the depth in inches and pounds of total insulation required for this job. In order to find the right calculator divide the attic floor space by 300 sq feet. Measure the length of your attic in feet.

This calculator is to be used as an estimating tool only. Square footage relates to the floor area only and does not factor in the height of the attic space. Ventilation manufacturers assign an nfa value to the non motorized vents they make. 1 cubic foot is 12 x 12 144 cubic inches.

How to calculate the cubic feet of an attic. Measure the length and width of the attic floor space to be ventilated.