How To Figure Roof Shingles

Calculate the size of your roof and estimate how many bundles of asphalt shingles rolls of felt and squares of roofing material are needed for a new roof.

How to figure roof shingles.

A square of shingles is the number of shingles needed to cover 100 sq feet of roof area. To accurately calculate the area of your roof you must first determine its slope or pitch. The rise is the distance from the top of a stud wall to the peak of the roof. Place the end hook of the tape on the corner and run it all the way to the opposite corner of the house.

Dimensions measured from the ground. Roof pitches are described in terms of rise and run. However shingles are packaged in a way that they are light enough for the average person to carry around. You will then have to get the measurement of the rake of the roof.

Measure your roof accurately use a measuring tape preferably 50 or 100 feet long and get exact ground dimensions of your house. You will need to express this size in terms of square feet. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. Keep in mind that the average size of a roof is 1 700 square feet so your total will likely be 10 higher or lower than this figure.

Measure both the width gable side and the length eave gutter side. It is often compared to slope but is not exactly the same. Measure the length and width of each portion of the roof multiply length by width for each plane and then add the planes together for the total square footage. If the existing shingles are standard 3 tab shingles you can get this measurement by taking note of the number of tabs along the eaves and ridges then determine the length in feet.

A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally. As a rule of thumb there are 3 bundles to a square assuming that you are using three tab strip shingles. Add the price per square of materials to get an estimated material cost. To do this you need to note that one tab will be equal to 1 foot.

How roof pitch is calculated to accurately calculate the area of your roof you must first determine its slope or pitch. The run is the distance from the outside edge of a perimeter stud wall to the center of the house. Roof pitch is the measurement of a roof s vertical rise divided by its horizontal run.