How’s this for a wall assembly?
Drawing attached: 2×4 studs; 1″ x 2″ spacers—made from foam panels—glued to studs as required; plywood sheathing nailed to studs (1″ space provided by spacers); minimum 2″ closed-cell spray foam filling up the space between plywood and studs, and another 1″ of stud bays also. This would provide a thermal barrier; an air barrier; a vapor barrier; a lot of shear value and overall strength; if windows are nailed to the plywood it would provide a complete seal there also; it would provide a continuous seal around outside corners and at all rim joists. 2″ of closed cell foam = R-13; add another 2 1/2″ of dense packed cellulose for an R-22 assembly. If required a higher R value could be achieved by adding foam under siding or going to a 2 x 6 assembly.
Clearly some jigs would have to be made to speed up the assembly, but for the extra hassle it seems to solve a lot of problems and offer a lot of benefits. Am I crazy?
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