Found this today on an inspection. I wanted to know if any of you guys have seen this before? The plumbing vent stacks and flashing boots were melted above the roof shingles. They were located within 10 feet of the chimney. The chimney had a large horizontal separation crack inside the attic under the roof decking, but there were no signs of heat damage to the vent stacks inside the attic, only at the exterior. This was a pre-listing inspection for my client, and they are the original owner. There is no history or evidence of any chimney fires. It gets hot here in Atlanta during the summer months, but not hot enough to melt PVC. The roof has been replaced within the last 11 months. Any ideas? (See attached photos) Thanks for any feedback.
The homeowner did not know. The roofing contractor did not mention anything to the home owner about the vent stacks and boots being damaged. It might of happened after the new roof was installed.
Thats an expensive jack to use on a comp roof what a waste of money. Its a lead jack typically used on tile roof waste vents. They cover the entire waste vent & are folded down inside the ABS water tight & ugly.
Picture #2 was about 7 feet from the chimney. Picture #3 was directly behind the chimney. There appeared to be more damage to the vent stack furthest from the chimney. The roof was recently replaced, so there were no signs of damaged roof shingles, no signs of excessive heat or damage at these areas underneath the roof decking inside the attic. I am wondering if there may have been enough heat coming from the separation crack inside the attic at the chimney to cook the underside of the roof decking and previous shingles to cause the plumbing vent stacks & boots to melt. The chimney has a metal flue pipe that ran through the brick chimney chase. Could there have been enough heat radiating from the metal chimney flue pipe to cause high enough temperatures to melt the PVC plumbing vent stacks & boots? It sounds far fetched, but I’m not sure what else could have caused enough heat to melt the PVC plumbing vent stacks.
The metal flue pipe should be a B-vent which only requires a one inch clearance.
I would have the owners replace both pvc vent stacks at roof by cutting them off in attic and attach new extensions and have tuckpointing repair at chimney to avoid any problems with potential buyers.
You may also recommnd a A Level II Inspection for fireplace to be on the safe side.
Yes. The furnace & water heater type B vent pipes were located at the backside of the roof. I verified that both melted PVC vent stacks were originating from the bathrooms below.
