Joe Van Sweden, owner of Ark Design Construction & Roofing which recently installed new roofing on the Palo Cedro Village Shopping Center, knows residents will be curious when his crews start working on the roof over Holiday Market again, so he asked us to explain what is going on. Van Sweden explained that when Ark Design roofers began the project to replace the old wood shake roof with new fire and wind resistant composition shingles, they were concerned about the abrupt shift in roof pitch between the main roof and the covered walkway in front of Holiday Market. The problem was accentuated by the use of 5/8-inch plywood on the main roof and 1.5-inch tongue and groove decking over the walkway. To mitigate for the uneven roof surface over the front wall of the store roofers installed a tapered Perlit filler strip to fill the gap. Despite their efforts and despite the fact the they were installing high quality Class A shingles according to the manufacturer’s specifications, the roof began to leak on both sides of the front wall during last month’s heavy rains. As soon as the weather allowed, crews from Ark and the shingle supplier were on the roof trying to figure out what had gone wrong. What they found was that because the shingles are designed to seal together to increase their wind resistance, (they are warrantied to withstand winds up to 130 mph) they can also trap water under certain circumstances. The trapped water got under the shingles and ran down the roof, collecting in the pitch change area where it eventually found a way through [probably via nail holes] and showed up as leaks. The shingle manufacturer, which Van Sweden does not wish to identify because the company is fully backing its warranty and paying for all repair costs, has come up with a solution to the problem. The Ark Design repair crew will remove a four-foot wide section of shingles on either side of the pitch change area and install a self-adhering, rubberized under layment that will seal the nail holes and send the water on down the roof, preventing it from pooling and seeping through. Van Sweden also said that the shopping center’s owner Gabrielson and Company had offered to pay for additional “feathering out” of the pitch change by installing a 24-inch wide filler strip instead of the 12-inch one already in place.