sealing roof jack

[chetwynd]

Hi,

The project I'm working on is actually electrical, but the same question applies. I have a piece of galvanized 3/4" pipe going down into a roof jack on a garage. Right now it's sealed with some kind of tar or putty or something that looks like it's been there forever. I need to replace the piece of galvanized pipe, and will then have to reseal where the pipe goes down into the roofjack. What should I use? 20mil tape?

Talk to me fellas!

THANKS!

[master plumber mark]

jsut buy a tube of clear silicone

it works great

[hj]

Or a tube or can of roofing cement.

[Cass]

Thoes will do the job.

[modbit]

That will work or roofing bull.

[bluebinky]

Just in case you didn't already know, you should use rigid conduit instead of plumbing pipe for electrical.

Of course, that has nothing to do with sealing the roof penetration...

[hj]

The only real difference is that electical conduit has a straight thread, but I do NOT think electrical nipples are any different than plumbing ones.

[bluebinky]

Plumbing pipe isn't "approved" for electrical work. Not a big deal, other than an inspector might notice...

[kreemoweet]

Electrical conduit is deburred, both at the threaded ends and internally. That is most emphatically not the case with the plumbing nipples sold
most places, which could easily damage wiring pulled thru them. It is a big deal.