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Bad Roof Design

Launch Slideshow

Bad Roof Design

How IR scanning traced a leak to a flashing

Bad Roof Design

How IR scanning traced a leak to a flashing

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    When we arrived, we found the usual assortment of buckets on the floor.

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    Though you may not be able to see it in the photograph, there was a slight bulge in the drywall ceiling but no other signs of moisture.

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    The moisture meter, however, read off the scale when placed on this spot.

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    An IR image showed a concentration of moisture. (Note also the dark square areas to the right of the moisture spot; these indicate voids in the cathedral ceiling's insulation.)

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    The root of the problem turned out to be poor roof design.

In this case, the homeowner had already replaced the roof three times, seeking to cure an ongoing leak. The roofing contractor was now insisting that replacing an upper section of the roofing would fix the leak, but the owner wanted to try our services first. When we arrived, we found the usual assortment of buckets on the floor (see slideshow). After talking to the owner about the problem, we turned on our camera and went to work. Though you may not be able to see it in the photograph, there was a slight bulge in the drywall ceiling but no other signs of moisture. The moisture meter, however, read off the scale when placed on this spot, and an IR image showed a concentration of moisture. (Note also the dark square areas to the right of the moisture spot; these indicate voids in the cathedral ceiling’s insulation.)

The root of the problem turned out to be poor roof design. In heavy rains, water from an upper roof cascaded onto the lower steep-slope roof, where it was directed back against the building and in around the poorly executed counterflashing on the wall, eventually finding its way into the living room ceiling. Our recommendation was to install a new wide cricket flashing, taller counterflashing, and gutters on the upper roof to redirect the bulk of the water.