Clay S Tile roof, no secondary flashing


#1

Hi,
Homeowner in Palm Springs CA with S-Tile (clay or concrete, not sure) roof, about 18 years old. Not much rain here.
There does not appear to be any secondary flashing above the underlayment on the roof deck where PVC plumbing vent stacks and sheet metal roof vents are installed. Everything seems to flashed only against the roof underlayment.
There is however have some type of mortar (very crumbly, now) built up around the vents to cover the holes / cuts in the tile and generally taper the vent toward the tile. I think the mortar is in place for visual appeal only. The mortar does not appear have any water shedding function.
So was secondary flashing around roof tiles not customary or required buy code 18 years ago?
Any comments on the mortar’s purpose around the vents?


#2

Post some pics but sounds like it would be a good idea to install some lead pipe colars.


#3

All of this was probably covered by the TRI installation manual (industry standard) 18 years ago. Even if it was not mentioned, doing so is a simple and well-known “best practices” installation technique. Using mortar as a primary flashing at a roof penetration / tile junction is just dumb; even for dry Palm Springs. Pipes stick up and are constantly vibrating in the breeze and wind. Mortar at the base of a pipe can’t take the vibration.

Flashing your pipes with mallebale lead will be your best bet at the primary flashing level.


#4

Thanks for the feedback. I added a picture to the original post that shows the mortared vent penetrations pretty clearly.
I think I’d want a roofer to pull about 4 or 5 tiles wide up from the bottom and properly re-flash the skylight and vents like in the attached diagram.

Yes?


#5

That is correct, go with lead or copper, NOT aluminum. 2# lead is more than ample, not sure where they came up with 2 1/2 # Might be a typo.