1/4 inch larch plywood.1/4'' thick spruce veneer ply.used 1.5 inch nails to secure the plywood to the ceiling joists first, after establishing a cut pattern, then used decking screws to attach the 1X 4 strapping, which hid the cut lines as each panel was cut and applied separately.
Do in Kitchen. 46.167" sq with 6" w trim
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