Calculating Attic Size

If this distance measures 4 inches you have a 4 in 12 pitch.

Calculating attic size.

Measure the length of your attic in feet. We also need to allow for the floor system in our calculations. The word denotes the framing or composition which helps that covering also. So draw up a simple cross section showing the outside wall a rafter set at the correct pitch and a floor system.

Make sure to measure in the center at the attic s highest point. Click the button to calculate the depth in inches and pounds of total insulation required for this job. Next we need to calculate the 5 and 8 ceiling lines. How to size attic exhaust vent fans for your home attic size.

Cfm cubic feet per minute is a measure of the amount of air the fan moves in a minute. 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. Measure the height of your attic in feet. Attic truss room size calculator a rooftop is part of a building envelope.

Input length width and desired r value of the area to be insulated. 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. 8 inches and you have an 8 in 12 pitch. 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. This calculator is to be used as an estimating tool only. Divide this number by two. Pitch measurement method 2.

To determine the size of your attic multiply the width by the length of the attic floor in feet. Measure the width of your attic in feet. Measure the length and width of the attic floor space to be ventilated. The formula above gives an approximate value of the cfm needed for an attic fan.

Click to see full size image. I ll do this on the right side of the house which is a 12 12 pitch. On a ladder beside the roof place the level a foot or so up the roof hold it level and measure from the 12 inch mark on the level s bottom straight down to the roof.