How To Measure A Roof
Getting accurate roof measurements can be difficult but with this roofing calculator, you’ll be well prepared to take measurements of any roof. Whether you’re a contractor looking to train a new employee or a homeowner looking to do some renovations, you’ll find this guide helpful for any roofing project. Use the step-by-step guide below to accurately measure your roof and estimate roofing costs.
Satellite Roof Measurements: Features of a Roof Report
- Accurate Roof Pitch Measurements
- Roof Measurements including Area, Rakes, Ridges, Hips and Valleys, and every edge is separately measured and identified.
- CAD style drawings with colored lines identifying every type of roof edge
- Online access to your Roof Reports for your Employees, Subs and Suppliers with no software to install
- Multiple image providers for over 98% coverage of the USA & Canada
- Also supports file formats such as XML,RXF,DXF/DWG AND WRL
MEASURING THE PITCH
To calculate the area of your roof, first you’ll need to calculate the pitch of it:
- First, use your measuring tape to measure 12 inches on your large level and make a mark at the 12-inch line.
- Next, place your ladder against your house at the gable end.
- Climb to the top of your roof.
- After that, place your level against the gable trim and flat against the side of the house.
- Using your measuring tape, measure from the 12-inch mark on your level up to the bottom edge of your gable trim. This number is your rise.
- Each rise measurement is written as “# in 12” and this is your roof’s pitch. (For example, if your rise is 4 inches, your roof’s pitch is 4 in 12.)
CALCULATING THE AREA
If you want to get the exact area measurement for your roof, you can follow these steps:
- Once you have your roof’s pitch, divide the number by 12. (For example, if your roof’s pitch is 4 in 12, you would divide 4 by 12. This would yield 1/3.)
- Next, square your result. (If your number is 1/3, squared would yield 1/9.)
- After that, add 1 to your number. (1/9 + 1 = 10/9.)
- Next, figure out the square root of your new number. (The square root of 10/9 is 1.05.)
- Next, use your measuring tape to measure the length of your house. (Be sure to include overhangs.)
- After that, measure the width of your house. (Be sure to include overhangs.)
- Multiply your house length by your house width to get the area. (For example, 40 feet x 30 feet = 1,200 square feet.)
- Next, multiply the area by your roof’s pitch. (1,200 x 1.05 = 1,260 square feet.)
- To allow for hips, ridges, and waste, add 10% of your final number for a gable roof and 17% of your final number for a cottage roof. (Your total number would be either 1,386 or 1,474 square feet.)
Acreage Calculator – Measure the area of a plot of land
The easiest way to measure the acreage of a plot of land is to start by entering an address that is associated with the plot of land you need the area of. In rural areas where an address may not be available, you can enter the cross street or even the GPS coordinate of a point on the land. For GPS coordinates be sure to enter the latitude followed a comma then the longitude ex. (41.87811, -87.629798). In any case this will place a marker that you can use as a reference point to draw the area on the map. Once you are finished drawing the area calculator will display the area of the shape above the map.
How to use the google maps area calculator tool to measure a roof
Special precautions must be taken when measuring the area of a roof. The images that appear on google maps are often at a slight angle, which combined with the angle of a roof can cause errors. For this reason it is best to outline the roof at points which are all at the same elevation. On a simple house for instance you would only click on the corners of the roof and not on any points along the peak as that would cause an error. After measuring the area of the footprint you can estimate the actual roof area based on the angle of the roof. Similarly if you using the area calculator tool to measure a roof with multiple levels, you should do the individual section separately. The google maps area calculator is not 100% accurate. Do not rely on this tool as your only resource in making important decisions.