Board-and-Batten Siding Over CMU Block Wall
I am located in Virginia in climate zone 4. Clients have asked me to put vertical board and batten cypress wood siding on the north side of a house built with hollow 8″ CMU blocks. The house currently has no wall insulation, so this seems like a good opportunity to get some insulation at least on that one side. Is there any moisture-related danger to putting rigid foam on the outside of a block wall?
I would want to use at least 2″ of foam and fasten it to the wall with horizontal 2×4 strapping. I realize that every fastener I put into the block wall to hold the strapping will be a major thermal bridge so I want to minimize fasteners but have enough to hold well. Any suggestions on a reasonable number of Tapcons or some other fastener to use?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part