Tightening up a 1949 mid-century modern
I just bought a really cool 1949 mid-century modern 2200 s.f. split-level home in the Chicago area (Zone 5) and will be doing a bit of work to it. The work to the exterior consists of all new siding - cement fiberboard and cedar siding set over the existing sheathing as a rain screen on 1x4 furring strips. I will be adding 1 1/4” extruded poly where the cement fiberboard is going, and for aesthetic reasons, adding 2” extruded poly where the cedar siding is going. I will cover the sheathing with the a WRB. New orientation specific Integrity Low E windows will be set as ‘outies’.
I haven’t been able to verify what the existing insulation is (I don’t close on the property until June 20) - I will check this right aware. I believe the walls are 2x4’s and I am betting there is 2” thick fiberglass insulation with either a kraft face covering or a petroleum coated kraft face of some sort. If that is the case, I think I would be creating a double vapor barrier. Should I use expanded poly instead of extruded? I have read through many of the GBA articles and haven’t seen this come up.
Because the house will be significantly tightened up, I will be doing a few things to the mechanical system. The home is an open split level plan, meaning the air flows easily from the 2nd floor to the main level and across to the lower level. The mechanical system is a gravity flow - the furnace is in the lower level in a room that is all angled wood louvers on one side, and basically all of the supply air flows down to the lower level. There are no supplies in the lower level. This was apparently not uncommon in the late ’40’s.
I am adding a new sealed combustion/direct vent water heater and at this time keeping the existing gas fired furnace but connecting the outside combustion air supply. I will add an Air Cycler system to bring in fresh air. The exhaust hood in the kitchen is variable to a maximum of 300 cfm. The bathroom exhausts are in the 60 to 110 cdm range. What I would like to do is interconnect the Air Cycler to the kitchen exhaust so the fresh air is being supplied into the home in a more balanced way when the exhaust hood kicks in.
Any input would be great.
Posted Thu, 05/01/2014 - 11:28
Edited Fri, 05/02/2014 - 06:53
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