Ways to cut panel product claims

OR MOST building products dealers, "callbacks" or "claims" are four letter words. Since the best way to avoid mentioning claims is to avoid getting them, the following outlines the most common panel problems. and how to get rid of them.

A familiar cause of panel claims goes way back to jobsite delivery. If lumber and plywood at a construction site are dumped in the mud, directly onto uneven ground, this may decrease the material's performance. Structural panels are tough, but they will perform better if they are given a little attention.

Story at a Glance

Methods that cut callbacks eliminate most problems with proper jobsite delivery reducecomplaints with application recommendations.

First, find a level area where the plywood can be dropped. Find three scrap 2x4s, and use those as stringers for your stack Put two ofthem about a foot from either end, and the third in the middle. This simple procedure will keep panels out of the mud and give them even support.

It may sound ridiculous to recommend covering panels when they could be soaked on the house before it is closed in. But before the panels are installed, it's important to keep them from collecting moisture unevenly. Cover them with a tarp; and if the tarp is made of polyethylene, leave panel sides and ends open to keep from creating a "greenhouse effect."

Perhaps you've had panel buckling complaints. As the sun sinks into the West, you gaze at a two or three month old house and instead of a smooth line silhouetted in the sky, the roof is waving at you! After removing the shingles, the builder discovers the panels have buckled between supports.

According to the American Plywood Association, improper panel spacing is the most common cause of buckling. Wood tends to absorb moisture and expand until it reaches an equilibrium with its surroundings. Panels butted too tightly together have little room to expand in their horizontal plane, and may buckle upwards or downwards.

Panel spacing recommendations were recently revised to relieve some of the confusion about spacing at edges and ends. Formerly, panels were to be spaced l/4 inch at edges and l/8 inch at panel ends. But after comparing field performance and construction practices, APA issued a new recommendation. Panels are to be spaced l/8" at all edges and ends. You can suggest that builders use a nail to spaca all the way around the panel. That recommendation is consistent for wall sheathing, roof sheathing, siding or subflooring.

One way you can help builder customers assure good roof appearance is to recommend allowing panels to condition to a higher moisture content before the roofing is installed. A few days with air of 80 to 900/o relative humidity circulating over the entire panel surface will sufliciently condition the panels. If this approach isn't practical, suggest that the builder try to delay installation of shingles after the sheathing has been applied. Panels should be protected from direct rain exposure by applying the roofing felt as soon as possible.

Another thing the dealer should make the builder aware of when shingle ridging is discovered is to check for proper attic ventilation. The most effective attic ventilation is provided by a combination of eave

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