Here’s how to lay a no-squeak subfloor. Apply a generous bead of panel adhesive to the tops of your floor joists. Lay sheets of 3/4-inch tongue-in-groove plywood, staggering the joints as you go. Use a sledgehammer against a two-by-four to drive the plywood together tightly. Secure each sheet in place with galvanized eight-penny flooring nails.
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