My main strategy as a home inspector is to keep an open mind because even the most obvious good things about a house can throw for a loop.
This home had a new architectural shingle roof, so I was expecting the attic to look great. First glance showed new, OSB sheathing, which meant the roof replacement was "complete", meaning both shingles and sheathing was replaced. However, there was Chaetomimum mold, so it had to be a ventilation issue, right? A new roof wouldn't let anything through it! Yikes, but the darkened wood meant water penetration THROUGH THE BRAND NEW ROOF! What happened? Bad underlayment? The new underlayment has a self-sealing membrane--not supposed to let anything past it. The answer has to come after the roof is removed.
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