You can make a reasonably accurate estimate of your roof’s square footage without climbing up a ladder. Learning how to measure a roof from the ground will save you time. It’s certainly safer too. The roof size estimate will help you plan the expense of replacing a roof. You can price the shingles and other materials and prepare a budget for the job. If you’re house shopping and see a property with a bad roof, this process provides a quick way to calculate future material costs. The information could help you understand the expected repair costs if you want to make an offer.
Techniques for How to Measure a Roof From the Ground
For rectangular roof sections:
- On standard gable roofs with rectangular sections, you can count the shingles and calculate the size. This works because 3-tab shingles are about 12 inches wide by 6 inches high.
- Working left to right, count how many shingles that you see in a row.
- The number of shingles represents the section’s width in feet.
- Write down the width number.
- Count the rows of shingles upward from the gutter to the peak.
- Divide the row number by 2 to arrive at the height of the section in feet.
- Write down the height number.
- Multiple width by height to calculate square footage for the section.
- Repeat the shingle count method for every section of roof.
- Add all square footages for each section to get the total square footage covered by shingles.
For triangular roof sections, like dormers:
- Count the shingles across the widest part of the triangular section.
- Write down that number for the width in feet.
- Count rows of shingles from the gutter or lowest point to the roof peak.
- Write down that number for the height in feet.
- Multiple width by height.
- The resulting figure will overestimate square footage but provide a close idea of how many shingles will be needed.
For hip roofs:
- Learning how to measure a roof from the ground requires a different approach for a hip roof.
- Get out your tape measure and measure the length and width of the house.
- Write down the dimensions.
- Multiple length by width.
- Multiple the resulting figure by 1.35.
- Use the result of that equation as the estimate for hip roof’s total square footage.