How to Estimate the Cost to Replace Roof Decking & Shingles

Replacing all the decking and shingles on a roof can appear to be a rather daunting task. The most nerve wracking part of the project for many is creating an estimate of the project costs. Getting a solid estimate can easily be done by breaking down the various components of the project and pricing them separately.

Instructions

1. Calculate the total square footage of the roof. Divide the square footage by 100 to determine the number of squares that the roof has.

2. Figure the amount of the roof decking by taking the total square footage of the roof and divide by 32 to get the number of sheets of plywood needed. Multiply that number by the cost of the plywood to arrive at an estimated cost for materials.

3. Calculate labor to replace the roof decking by estimating how long it will take to remove the old decking and install the new one. Multiply the man hours it will take by the average wage of the workers performing the task.

4. Add the decking costs and labor costs together to get the total cost to replace the roof decking.

5. Divide the roof square footage by 100 to get the number of squares the roof has. Multiply this number by the per square price for the desired shingles to estimate the shingle pricing.

6. Multiply the number of squares by the per square rate of the shingle installers to calculate the installation price of the shingles. Add the cost of the shingles to this amount to figure the total cost to replace the shingles.

7. Add the total costs to replace the decking and the total costs to replace the shingles together to get the grand total to estimate the cost to replace roof decking and shingles.

Tips & Warnings

• Standard 4 x 8 sheets of plywood have 32 square feet.