A roofing calculator is what the roofing industry to estimate how much a new roof is going to cost you. Even when using an online roofing calculator, though, you need to use your brain to make sure you have accurate roof measurements.

How to Measure Your Roof

Because most roofs are sloped, it is sometimes difficult to obtain accurate measurements to use for the roofing calculator. What you need to do to get accurate results is measure the pitch of your roof.

To do this, you will need a long ladder and a 3-foot long level tool and a measuring tape. About a foot up from the roof’s lowest edge, put one side of the levelling tool onto the roof’s side so that the levelling tool is the same angle as the ground. Measure how far it is from the level’s middle to the roof. To obtain the roof’s rise, divide the result by three (if you have a three foot level) or by two (if you have a two foot level).

Now go up to the attic. Place the small edge of the level alongside an angled beam. The level should be at an angle to the floor. Now measure how far it is from the middle of the level to the floor. Again, divide the result by either two or three. This will give you the roof’s run.

These calculations will give you the number of inches your roof tilts per flat foot. This is important information for the roofing calculator.

There are tools available which can do this for you, or you can hire a roofer to work it out.

What Next?

Next, divide the slope of the roof by twelve to work out the total square feet which will need roofing. Once you have that figure, and once you have decided which roofing material you want to use, you can estimate how much a new roof is going to cost. Alternatively you can put the numbers into an online roofing calculator, or hire somebody to work it out. They will use the same method described above to work out an estimate.