An understanding of shingle quantities is required to determine the cost to reroof a house. A square of shingles covers 100 square foot. There are three bundles of shingles in a square. Ridge row caps can be made by cutting one shingle into three equal parts. The ridge row caps are cut to allow for a six inch overlap and six inches of exposed shingles. A total of four nails are needed per shingle to secure it to the roof. Roofing felt is placed on the roof prior to shingling. Common roofing shingles weigh 107 Kilogram per square.

Draw a rough diagram of the roof to be shingled.

Measure the width and length of each area and write it down on the corresponding rough diagram.

Multiply the width by the length in each area to determine the square footage. Write the square footage down in the corresponding area.

Add the square footage amounts from each area. Divide the number by 100 to get the answer for how many squares are needed. Divide the square footage amount by either 200 or 400 to acquire the amount of roofing felt rolls necessary to complete the job. (Roofing felt is sold in either 200 or 400 square foot rolls.)

Add 10 per cent of the total squares of shingles needed for ridge caps, starter courses and waste.

Write down the total number of the squares of shingles required and rolls of roofing felt. Go to the local home improvement centre and select the type of shingles desired to complete the project. Multiply the cost of the shingles per square by the number needed. Do the same with the roofing felt rolls.

Choose between using a roofing nailer or hand nail to attach the shingles to the roof. Obtain pricing for roofing nails. Find out how much it costs to buy or rent a roofing nailer.

Add all the prices together to get the cost for reroofing a house.