How to Compute Ridge Cap Needed

The ridge cap covers the joint where sloped roof sections meet.

The ridge cap is the trim place along the roof's peak or ridgeline, where sloped areas of the roof meet at the top. The ridge cap covers over the joint created when these areas meet -- protecting the home from precipitation seeping through the exposed joint. Usually, the ridge cap matches the rest of the roofing material. Manufactured ridge caps are available, or you can cut a ridge cap from three-tab asphalt shingles. The ridge cap is installed last, after all the shingles are in place.

Things You'll Need

• Measuring tape
• Pencil
• Paper
• Calculator

Instructions

Manufactured Ridge Cap

1. Measure along the ridgeline on the roof with the tape measure, and record the measurement in feet and inches.

2. Add an extra 5 percent for waste. Use a calculator, if necessary.

3. Use the final total for purchasing the correct amount of manufactured ridge cap.

Hand-Cut Asphalt Ridge Cap

1. Measure along the ridgeline on the roof with the tape measure, and record the measurement in feet and inches.

2. Add an extra 5 percent for waste. Use a calculator, if necessary.

3. Multiply the number of feet by 12. Add the total to the number of inches, to convert the total ridgeline measurement into inches.

4. Divide the total inches of ridgeline by 5, to determine the number of ridge cap pieces needed.

5. Divide the number of ridge cap pieces needed by 3, to calculate the number of three-tab asphalt shingles needed.

References

• Roofhelp.com: Calculating Materials Asphalt Shingles