Installing Roofing Felt!

Let's Do It!

 Getting a new roof is not a big job, well it's not a big job if you're not doing it. Whether you are completing your own roof job or hiring a contractor, theres a few things to know about roofing. If for no other reason than to know it is being completed correctly. The first step of Roofing is installing the underlayment. Most notably Felt. Felt underlayment acts as a water proof barrier between the roof decking and the outer roofing material.
It is the first layer applied in roofing when using asphalt or fiber glass shingles. It comes in a 30 inch wide roll, and 2 sizes 15lb and 30lbs. The 15 lb roll covers approx. 400 sq ft. and the 30 lb roll covers approx 200 sq ft. Always apply the Felt to clean, dry roof  sheathing if possible. Always work from the bottom to the top. This will allow any water to flow down the roof and not collect in wrong way facing overlays, and resulting in roof leaks.

Putting down The Underlayment:
1. Install any metal or vinyl drip edges before laying the roofing felt.
2. We like to use a two man process. Starting at the bottom of the roof, we unroll about 6 to 8 feet of the felt roll and align it to the drip cap or the bottom edge of the roof and using a hammer tacker and 1/4 inch staples, tack it down every 6 inches along the bottom edge, and the left or right edge which ever side you started from. Always keeping the lower edge of the paper aligned with the edge of the roof or drip edge.
3. When you have completed this step, then have your helper continue to roll it out across the roof keeping it square and smooth. Stretch the felt tight. Not allowing any wrinkles. Mean while you continue across the roof tacking as you go.  In the event some wrinkles are created you should slice the wrinkle using your box knife and staple it down. The cuts may need sealing with roofing cement.
4. Secure the middle area of the Felt using a "W" pattern and stapling every 6 inches.   
4. Use a utility knife to cut the left and right edges even with the roof.
5. Return to the side you started on. Overlap the layer of felt paper you just tacked down by 2 inches, square it up on the edge and bottom then tack down the edge and bottom as before and continue on across the roof as before.
6. Continue this process up the roof overlapping each horizontal section by 2 inches and overlapping any vertical edge ends, by 4 inches. Switch to the other side of the roof before completing the section across the ridge.
7. Work your way up to the ridge on that side the same as before.
8. If not installing roofing vents then lay the last piece of felt overlapping the highest piece of felting on either side.

Notes:
Valleys: For Roofs that have valleys cut the felt paper at an angle to fit the valley. Then cover the rise separately.

Try to stay off of the felt as much as possible, it wil tear from heavy shoe soles.