Flue vent pipe cut down

[Beeek]

At new construction closing I had a leaky roof vented flue for my gas furnace. The flue leaked outside the piping onto the upstairs feeding duct work and down to the basement. The leak was determined to be inside the walls and another flue was vented out the side of house. leaving the old flue just sitting there. With this and capping the original flue at the top, no more leak.

To make lemonade out of lemons, I cut the "useless" flue up to make a cable riser for video/network wires that they left out of the house (no way w/o it to reach the attic). Like the hack I truely am, I removed the portion in the attic b/c I found moisture in the top portion when I cut into, and also I didn't want the boot to support the dead weight. The cut I made was about 1 ft from the boot/flash. The boot appears to be rubber like and goes up 9 or 10 inches and looks itself like a pipe from the outside of the house, with the PVC 2" flue top just poking out of it with the cap installed.

My question is, is it alright to allow it to stay like this, one foot of 2" pvc in the boot with a cap on the PVC? Should I have left the other 7-8 feet of 3" pvc dangling from it and just put two clamp hangers on each side?

When I move the pvc around in the boot I can see some light cracking through on the pipe, is this normal? The rubber like boot doesn't appear to seal as well as some manufactures would lead you to believe. It was raining when I was there and I could not detect a bad leak. I could try to put two pipe hanger clamps on the 1 foot piece, but I am affraid of off centering it and causing those cracks the light was shinning through to show up.

Me and my bright ideas.

Thanks in advance,
Beeek

[shinstr]

Your best bet is to remove the penetration entirely, repair the decking, felt and shingle.

If you still need a cable penetration, these are best placed through a wall or soffit and not through the roof.

Some genius did come up with a satellite mounting kit that looks and sets in the roof like a static or "pancake" vent...pretty cool..wish i'd thought of it. I'd be enjoying my retirement about now....20 years early.

[Beeek]

Thanks. Actually I am only using the bottom part of the flue for the cables. From basement to attic. The conduit stops now about 1 foot above the isulation in my attic. I removed the 8 feet of pipe going up to my roof, and just have a 1.5 foot piece of pvc sticking out of the roof flash/boot. (Above boot = cap, inside about 1 foot of pipe)

So I am guessing, like you said still the best bet would be to have the deck repaired. But in the mean time, any danger in leaving the 1.5 foot piece of pvc capped inside the boot?

Regards,
Beeek

[shinstr]

As long as its a tight fit so that it is sealed good.....no problem.
You could seal the pipe to the top of the boot on the roof side to be sure.