1985 vintage waterfront house - tearing out thermo-ply / #15 / 4"cedar lap and replacing windows. Typical contractor here is coming back with 5/8" CDX to build up the walls for wind code, then #30, and Hardiplank. I would love more of an air gap. Am I crazy? Hardi has to be nailed every 6 inches (making a furring strip rainscreen a problem) to pass wind inspection. I'm concerned about the top, inside edge of each lap grinding into the felt over the years, and the lack of a capillary break along that line. I'm considering adding a 2" wide strip of EPDM tape under the felt along these edgelines to cushion and create a hydrophobic barrier along that edge, and seal around nails. Also considering MTI 2" wide 1/8" thick "corrugated lath strips" along those nailing lines, for an actual air gap, and adding top and bottom venting. Maybe I should do both. Thoughts? |