Moisture entry into top of garage wall

Just finished inspecting a 2007 home with attached garage. Past moisture intrusion was noted on interior side of garage walls, and exterior vinyl siding showed staining from the siding drain holes starting high up the wall (first two images). Roof was in excellent shape and I doubt that it ever leaked. Shingles extended over gutter so I don’t think the water came from the roof.

Drywall on garage interior walls showed dry staining starting at the ceiling and wicked down the untaped seams (third image). One corner had mould growth which was dry.

Anyone have a theory on where this water was coming from? I know it’s not essential for me to determine the source of the water, but it would help the client out. I like to put things like “possibly from this or that, evaluation required” in reports.






Pretty obvious to me… no downspout extension for upper downspout… but I’m not being paid to diagnose any situation, so don’t quote me on that!

Well, I can’t see how that discharge would find its way across the roof, past the gutter, and into the wall below. But I always recommend adding a downspout extension to carry water over a roof surface to the gutter below.



I see staining that looks like that below ventilated soffits, moisture is coming from the attic, result of a failed vapor barrier and attic condensation, that would also explain the stained dry wall inside. However, the location of that downspout over the leak spot and that those soffits do not appear to be ventilated, Mr. Jonas’ conclusion can’t be ruled out. Does ice damming happen in your location?

Hi Erik, thanks for the reply. Your area (Edmonton) is my area, so yes ice damming happens, but as you know it doesn’t happen on a 2007 house like this one. No evidence of ice damming on the gutter or shingles, but your deficient vapour barrier could possibly be it.

My wife’s a realtor and I think she’s worked with you on an inspection or two! Of course I can’t ever work the same deal as her, conflict of interest and all. She said you were one of the good ones!