Cat IV Roof termination with plumbing stack flashing

[Mike Lamb]

Some instructions I have seen for roof vent terminations call for a flashing for PVC pipe. What would be the downside of using a lead plumbing stack flashing?

[Jim Katen]

None?

[Marc]

Squirrels love to bite into it.  I dunno why.

[Jim Katen]

Squirrels love sweet-tasting things. Lead salts are sweet. I suppose that the surface of lead that's exposed to the weather might produce some lead salts that the squirrels like. Combine that with lead's soft texture and it might explain why the squirrels love biting it. 

[Erby]

Seen a bunch of lead flashings chewed up by squirrels.  Though it seems to take longer than it takes for the rubber ones to dry rot.

 

[Jerry Simon]

On 10/29/2018 at 2:32 PM, Erby said:

Seen a bunch of lead flashings chewed up by squirrels.  Though it seems to take longer than it takes for the rubber ones to dry rot.

 

Not sure if I've ever seen rubber flashings for such; we use Neoprene boots around here, a synthetic polymer that weathers much better than rubber.

[Erby]

There's always that one dang grammar nazi hanging around, huh Jerry.

"Neoprene (also polychloroprene or pc-rubber) is a family of synthetic rubbers that are produced by polymerization of chloroprene. Neoprene exhibits good chemical stability and maintains flexibility over a wide temperature range."

My apologies for not being so specific as to include the word "synthetic' in front of rubber in my post.

😁 😁 😁

[Jerry Simon]

5 hours ago, Erby said:

There's always that one dang grammar nazi hanging around, huh Jerry.

"Neoprene (also polychloroprene or pc-rubber) is a family of synthetic rubbers that are produced by polymerization of chloroprene. Neoprene exhibits good chemical stability and maintains flexibility over a wide temperature range."

My apologies for not being so specific as to include the word "synthetic' in front of rubber in my post.

😁 😁 😁

Erby,

I've never seen Neoprene dry rot as you mentioned, so I figured in your neck of the woods they use rubber, not Neoprene.

Grammar Nazi?  Jeesh. . .

Edited November 2, 2018 by Jerry Simon

[Jim Katen]

I've seen them made from EPDM, neoprene, & silicone. 

In my area, the most common ones by far are made by Oatey. Those from the early '90s and earlier seemed to last forever, while those from the late '90s till about 2010 or so would deteriorate and crack at the drop of a hat. In the late 2010s or so, it looks like Oatey changed the formula - the "rubber" portion looks and feels different - it has a pebbled surface and is harder and less resilient. I've never seen one of these crack. Anyone else noticed this? 

[ejager]

10 hours ago, Jim Katen said:

I've seen them made from EPDM, neoprene, & silicone. 

In my area, the most common ones by far are made by Oatey. Those from the early '90s and earlier seemed to last forever, while those from the late '90s till about 2010 or so would deteriorate and crack at the drop of a hat. In the late 2010s or so, it looks like Oatey changed the formula - the "rubber" portion looks and feels different - it has a pebbled surface and is harder and less resilient. I've never seen one of these crack. Anyone else noticed this? 

I had one the other day; all the flashings were changed when they re-shingled about 5 years ago, so cannot sure where this boot sits in the formulation timeline, but it has that pebbled surface. The other boot on the same job was just fine.

[Jim Katen]

That's not the kind I'm seeing. They have a steel base and the pebbled rubber is shinier. 

[ejager]

Interesting how things vary from location to location.

The metal base kind went out of fashion for plumbing stacks a while ago here in favour of the all rubber, and that more frequently now its the newer thermo-plastic base with minimal rubber around the stack only (https://www.oatey.com/2375038/Product/Oatey-Thermoplastic-No-Calk-Roof-Flashings-Standard-Base_

 

Still see the metal base with rubber for electrical masts, sometimes more than we should. 😄

[Jim Katen]

I like the way they just sit on top of the shingles in the happy-go-lucky, carefree way. 

 

 

[DCBuildings]

Actually, if the original flashing was cracked, then sliding new flashing down on top of it like these pictures would generally fix the water intrusion in most cases, possibly getting years more life for the cost of the $5 boot. Toss in a little silicone between the boots and Bob's your uncle. You could even cut the flats off the 2nd boot, and just slide the bell down with caulk... if you don't like the happy-go-lucky appearance

[Marc]

7 hours ago, DCBuildings said:

Actually, if the original flashing was cracked, then sliding new flashing down on top of it like these pictures would generally fix the water intrusion in most cases, possibly getting years more life for the cost of the $5 boot. Toss in a little silicone between the boots and Bob's your uncle. You could even cut the flats off the 2nd boot, and just slide the bell down with caulk... if you don't like the happy-go-lucky appearance

Sort of like the flashing/counter-flashing concept, but I still wouldn't do it.  I like clean, straightforward construction.

[Bill Kibbel]

7 hours ago, DCBuildings said:

Actually, if the original flashing was cracked, then sliding new flashing down on top of it like these pictures would generally fix the water intrusion in most cases, possibly getting years more life for the cost of the $5 boot. Toss in a little silicone between the boots and Bob's your uncle. You could even cut the flats off the 2nd boot, and just slide the bell down with caulk... if you don't like the happy-go-lucky appearance

Repair collars, without the flange,  are available.