Calculating Attic Size

The formula above gives an approximate value of the cfm needed for an attic fan.

Calculating attic size.

Measure the length of your attic in feet. Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. Attic truss room size calculator a rooftop is part of a building envelope. 8 inches and you have an 8 in 12 pitch.

How to size attic exhaust vent fans for your home attic size. Attic fan size cfm 0 7 x sq ft area of the attic formula 1 the size of an attic fan is calculated in terms of cfm. The word denotes the framing or composition which helps that covering also. To determine the size of your attic multiply the width by the length of the attic floor in feet.

Next multiply the square feet of attic space by 0 7 to get the minimum number of cubic feet of air per. Measure the length and width of the attic floor space to be ventilated. We also need to allow for the floor system in our calculations. Click the button to calculate the depth in inches and pounds of total insulation required for this job.

It s the covering on the uppermost part of the building or shelter which gives protection from pets or animals and weather notably rain or snow but heat also sunlight and wind. If this distance measures 4 inches you have a 4 in 12 pitch. Pitch measurement method 2. Make sure to measure in the center at the attic s highest point.

Input length width and desired r value of the area to be insulated. I ll do this on the right side of the house which is a 12 12 pitch. Divide this number by two. How to calculate the cubic feet of an attic.

This calculator is to be used as an estimating tool only. Measure the width of your attic in feet. Click to see full size image. This attic ventilation calculator computes the size and number of solar powered attic fans to achieve the proper ventilation for your attic.

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. Next we need to calculate the 5 and 8 ceiling lines. So draw up a simple cross section showing the outside wall a rafter set at the correct pitch and a floor system.