NW-Bound
Give me a museum and I'll fill it. (Picasso) Give me a forum ...
- Joined
- Jul 3, 2008
- Messages
- 35,712
Yes, that's what I thought when I bought the house.It seems like those roofs should last forever in Az. Just what causes them to fail?
My house was built in 1986, about the same time as many houses here in this neighborhood. In walking through the area, we have seen so many houses with roof leaks being worked on.
My tiles are not clay but made of concrete, with a glazing on top to give it the red color. Too lazy to go out to take pictures, I found on the Web a house with exactly the same tiles I have. These tiles are tough enough that one can walk on them without breaking. Of course if a guy weights 300lbs, that's another matter, but I have not seen such a heavy roofer, have you?
These tiles of course should last forever. I believe it is poor workmanship that allows water to get underneath the tiles, eventually ruining the felt layer and entering the house. In the picture above, you can see that water hitting the walls of the upper story will run down the walls and get underneath the tiles if the flashing is poorly installed. In my case, another bad spot was around the skylight, where flashing is used to divert water around the dome. Any time there is such a break in the roof surface, it is a potential spot for water to get underneath the tiles. I also have a leak in a shallow valley, where valley flashing is the intended channel for the water to flow down on. Some leaves have accumulated there over the years, unknown to me, and caused a dam backing up the water, and made it spilled over to the surrounding felt.
With the "wavy" tiles like mine, strong winds can drive rain water under the top rows of the tiles, meaning the rows immediately below the roof crest.
There is also the kind of flat tiles, like the picture below. These lay flat against the roof, leave minimal gaps, and are easier to seal with flashing. However, these do not have a hollow airspace underneath and conduct more heat into the roof, I was told.
In my case, the concrete tiles are lifted up, the underneath felt layer is replaced and the tiles reinstalled. Most of the cost is for labor, and the material cost is not bad.
The real clay tiles that are installed with mortar are another story. See picture below. These would have to be broken up, and the entire roof reinstalled with new tiles. I have seen houses in my neighborhood like that. Ouch!