Tile sheds water; underlayment stops it
Tile is a shell that sheds most rain and shades the roof. Water still gets under it in wind-driven storms. The underlayment, a waterproof layer on the deck, is what keeps that water out of your home.
Years of attic temperatures well above the air temperature dry underlayment out until it cracks, especially on south- and west-facing slopes. Once it cracks, the next heavy storm reaches the deck.
Signs the underlayment is failing
- The roof is around 20 years old or more
- Leaks show up in different places after storms
- Ceiling stains with no obvious broken tile above them
- Brittle, torn or crumbling underlayment visible at eaves or under a lifted tile
- Daylight or water marks on the decking from the attic
Re-felt or replace?
If the tile is in good shape, a re-felt (also called a lift and relay) replaces the underlayment and battens and reinstalls the original tile, with broken pieces replaced. It costs less than a full replacement and keeps the look your HOA approved.
If many tiles are broken, the profile is discontinued, or you want a different material, a full replacement can make more sense. An inspection with photos will show which fits your roof.
Quick answers
How long does tile roof underlayment last in Las Vegas?
Typically 20 to 25 years. The tile itself often lasts 50 years or more, so most Las Vegas tile roofs need new underlayment well before the tile wears out.
What is a tile roof re-felt?
A re-felt, or lift and relay, replaces the underlayment under a tile roof while reusing the existing tile. The tile is lifted, new underlayment and battens go down, broken tiles are replaced and the tile is reinstalled.