bobcamarda

Yesterday I was called to look at a house that had a Coca-Cola colored stain along one area of one exterior wall. The majority of the stain had already been cleaned off but I could see traces of what was there. Too bad I couldn’t see the original pattern of the stain or the actual substance before they cleaned it. The little that was left was hard to the touch - not gummy. The house is a 2-story colonial, 11 years old, siding is horizontally oriented and painted cedar clapboard, and it is located in Redding, Connecticut. The stained area is on the west side gable wall from not quite the top of the roof, extending to the ground and about 10 feet wide. There is a 12 or 15-inch roof overhang on this gabled side. The owner first noticed the stain back in December after a heavy rain. It has not appeared anyplace else or any other time. When I entered the attic I immediately noticed drip spots on the floor and rusted roofing nails. Further observation revealed an excess of mold on the roof and wall sheathing covering about 200 square feet. This is in the corner of the attic adjacent to the affected exterior wall. Sure enough, the master bath exhaust fan was exhausting into the attic space beneath the attic floor deck plywood directly below this area. I did not get onto the roof to check there for something that could be dripping SIDEWAYS off of it. There have been no new appearances of the staining since. How likely is it that the humidity in the attic is permeating the sidewall and creating something that is leaching out through the siding and dripping down the side of the house (assuming a typical wall structure there: plywood, building paper and siding)? Or, can anyone offer another possibility… Thanks for your input. Bob Camarda Cornerstone Building Inspection Fairfield, CT