Multiplier For 3 12 Roof

Simply locate a roof rafter board place the end of the level against the bottom edge and measure from the 12 inch mark vertically to the bottom edge of the rafter.

Multiplier for 3 12 roof.

Next multiply the footprint of the roof by the multiplier below for your roof pitch to find the overall roof area. The pitch of the roof is the rise over a 12 inch run. That gives you 5 590 square feet which is the actual area of the surface of the roof. A roof pitch multiplier also called a roof pitch factor is a number that is multiplied by the area covered by a sloped roof to produce the area of the actual surface of the roof for roof slopes expressed as x in 12 rise in run the roof pitch multiplier is determined by finding the square root of rise run 1.

The value arrived at 928 reflects the square feet of the roof. And for a roof with a slope of 6 12 that number 1 118 is your roof slope multiplier. Roof pitch degree table. It affects walkability as well as drainage and roofs in areas of high rain.

We included a roof pitch chart below the 7 12 example image and the calculator below that. Roof pitch area multipliers. Roof pitch is a determining factor for cost of the roof as well as the roof area and the type of materials used. For example a 4 12 pitch roof that is 100 square feet.

Since pitch is the rise over a 12 inch run divide the run by 12 to get the multiplier in this case 120 12 10. The calculator above can handle much of this math. 800 multiplied by 1 16. We excluded roof multipliers for pitch below 3 and above 12 for the following reasons.

For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches. Image 1 12 to 12 12 roof pitch 7 12 pitch. 48 10 4 8. This will give you the rise over run or pitch.

Also the multiplier is so close to one that it does not really change the total size unless your roof is something like a 100 100. Multiply 20 and 40 which equals 800. If this isn t practical then perform the same measurement on the underside of the roof. Use our roof pitch calculator to find the pitch of your roof.

Divide the rise by the run the run is 12. For example if you measure 4 inches the pitch of your roof is 4 12. 100 1 054 105 4ft 2. Find the value of 7 12 from the roof slope multiplier table which is 1 16.

Outside of the u s a degree angle is typically used. Roof is 6 12 pitch and measures at 2 400 square feet so 2400 x 1 12 2 688 2 88 sqs added for pitch. If the home measures 20 x 40 and has a 7 12 roof then to calculate the slope of the roof follow these steps. Now divide the rise by the multiplier to get the pitch eg.

Get your roof size by using this roof pitch calculator. With pitch under 3 you can easily walk on the roof to get the exact measurements as that is usually a flat roof.