Plumbing Vent Problem

Has anyone ran into this before and know what might have caused it? It looked like something blew out of this plumbing vent and stained the roof.

That is very likely.

I might add that this was a newly remodeled home. It almost looked like watered down paint.

Well, imagine a back-up with the drain pipe full of paint from washing brushes. Or, someone attempted to get some drain-o up there, lol.

I my area, once a year or so they pressure wash the sewers. Literally. The backup does reach up vents pretty high.

Yes this would make sense. Thank you for your replies! Just wanted to give some explanation to the client.

1 Like

I would also put some of this back on the seller. I would instruct the client to ask the seller for more information.

What may have happened, the owner or someone hired, poured bleach down the vent. Likely to combat drain odors. Best not to hypothesize in the report.
Roofing: Composition shingles. California Woven valleys. <4/12 slope.
Observation: Stained shingles. The stain runs downstream from the upper most DWV pipe stack to the gutters. Width ><10"-12" wide. Splash or spill mark staining was also observed to the right of the vent and on top of the galvanized steel wind turbine beside the spillage stains.
No apparent physical degradation to the composition shingles observed the day of the inspection.
Refer to the vender for disclosure.
Recommend: A licensed roofing contractor further evalaute and service the roof prior the onset of winter.
Act upon any recommendations therein.

*Note: Composition shingles are manufactured using two or more layers of asphalt that are fused together as compared to 3 tab shingles that use one strip. The added thickness makes Composition shingles more durable.


Yes great feedback guys! Thank you both for your input! Have a great day inspecting!

1 Like