How Much To Overlap Roofing Tar Paper

Step 5 secure ends.

How much to overlap roofing tar paper.

If you have a vertical seam where one piece ends and another starts make the overlap at least 6 inches. There are pre printed lines on the tar paper that help show you where to end the overlap. Get help to lay the first sheet onto the roof. And even though it is thinner it is just as strong as felt and less resistant to ripping.

Usually 2 inches is plenty on a horizontal seam. For roof pitches of 5 12 to 7 12 use a factor of 1 3. The answer is the number of square feet of. There should be no wrinkles or other spots that could catch moisture and cause problems.

Overlap top of foundation. Be sure the tar paper lies in flat strips that are absolutely smooth. The vertical overlap should be at least 2 feet or 24 inches. All nails should be placed at least 12 inches away from the center of the valley.

Step 6 overlap next roll. Underlayment should cover the entire roof deck. Secure the outside edges with plastic capped roofing nails at 12 inch intervals. When unrolling the next adjacent roll allow for at least a two inch overlap.

If your roof pitch is 3 12 or 4 12 multiply by 1 25. This correction factor will take into account the greater area of the roof due to the pitch. Nail the two rolls in the overlap at 12 inch intervals. Afterward multiply them to calculate the area.

Some roofing felts are actually glued down. However the additional overlap may alter the spacing of the felt courses relative to the sheathing creating problematic conditions for fastening the felt to the sheathing. When transitioning into the valley underlayment should overlap the ice and water shield previously installed along the valley by 6 8 inches. Fit the first sheet.

As long as the wood on your roof is in good condition you can go ahead and put tar paper down. This will help give you a moisture barrier on the roof. Even if there s older tar paper in place you should simply rip it off and replace it. Multiply the total area determined in step one by a correction factor to account for the roof pitch.

Continue this for each surface of your roof. Felt underlayment can overlap more than 2 inches to provide an adequate barrier. For example if its length is 120 inches 10 ft and its width is 240 inches 20 ft the area is 28 800 square inches 200 sq ft. Roll the roof paper up and over the peak.

Repeat this until the entire roof is covered. The overlap of 3 8 should be followed consistently for a smooth look once the shingles are installed. Measure the width and height of each section separately. Overlapping up to 6 inches can provide a superior felt layer.

Make sure the rolls overlap by at least four inches and staple them into place on the wood. This paper is a new and in some aspects improved material for roofing underlayment.