How To Install Roofing Paper

Installing roofing paper, or felt, is an essential element to construct a waterproof roofing system. It also acts as a layer of insulation and water protection underneath roof shingles. Installation is not particularly tough when following these simple steps that will ensure a successful project.

What Is Roofing Paper or Felt?

The black rolls of roof paper or felt are made with asphalt and are normally available in rolls. The felt provides a layer of additional weather protection between the roofing finishing material (shingles, tiles) and the roof decking. The most common size width for rolls of roofing paper is 36 inches. It is commonly called 15lb paper. Many rolls are pre-striped allowing installers to keep a straight line when applying roll strips to the roof side by side. All drip edges along roof eaves, valley liners and flashing need to be installed before the roof paper layer is laid down. Only a drip edge along the roof rakes is installed after the paper.

Step 1 - Prep the Area

An assumption is made all materials are ordered based on the necessary measured requirements. Clean the decking as well as possible, making sure it is moisture free with no debris. Make sure all your roofing planks are secure with no nails protruding. Examine the entire decking area for any stray nails. A good tip is to run a flat head shovel along where the surface is. If the shovel stops, you’ve found a protruding nail. Either pound it in or remove it. Make sure there are no splinters protruding as well. You’ll need to remove these and sand the area a bit to ensure a smooth roof installation.

Step 2 - Roll it Out

Start at the bottom edge of the roof and roll the paper roll out toward the peak.

Step 3 - Overhang Paper

Allow for a ½ inch overhang of paper down each side of the roof when unrolling the paper. This overhang will ensure water will not enter underneath the paper getting trapped on top of the wood roof planks.

Step 4 - Over the Peak

Roll the roof paper up and over the peak.

Step 5 - Secure Ends

Secure the outside edges with plastic capped roofing nails at 12-inch intervals.

Step 6 - Overlap Next Roll

When unrolling the next adjacent roll, allow for at least a two-inch overlap. Nail the two rolls in the overlap at 12-inch intervals. Repeat this until the entire roof is covered.

Step 7 - Trim Excess

Use a utility knife to trim all excess paper on the last pass.

Remember to always overlap roof paper at valley, ridges, and hips by six inches. Cut a slit from the side of a paper roll to accommodate vent pipes. It's best to wear gloves and protective eyewear for safety purposes. Pay special attention to movements on top of any roof. This is a very dangerous place to be and caution is always necessary. Make sure all materials and tools sitting on top of the roof are secure.