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Q.Is it okay to glue OSB or plywood sheathing to the wall framing before fastening the sheathing with nails? It seems that this would be a simple and cost-effective way to add strength to a wall assembly while reducing air infiltration.

A.Bryan Readling, PE, senior engineer at the APA/Engineered Wood Association, responds: That's probably a bad idea. Although glue may indeed make a framed and sheathed wall stronger, the APA provides design values only for nails, due to the high variability of field-applied adhesive performance. You'd still need to follow the same fastening schedules, so the glue would be redundant.

Also, the load-deformation characteristics of nails are often much different than they are for adhesives: The glue connection would have to fail before the nails ever saw any load. Adhesive connections tend to fail more dramatically than nails, which give more warning. Nails are also superior in cyclic seismic loading, since more deformation means more energy absorbed through damping, similar to how shock absorbers work with the springs on your vehicle.

In addition, plywood and OSB already provide good resistance to air infiltration when used with an adequate housewrap, and they won't be improved much with extra glue.

Finally, note that the APA's Engineered Wood Construction Guide (Form E30, available free online at www.apawood.org), states: "To minimize the potential for panel buckling, gluing of wall sheathing to framing is not recommended, except when recommended by the adhesive manufacturer for wall sheathing that already has been permanently protected by siding."