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Addition and retrofit Manual-J collaboration

welivehonestly | Posted in Mechanicals on

Hi all,

I am a professional engineer (electrical, not mechanical) taking a crack at doing my own Manual-J for our addition/retrofit project.

Anyone interested in doing this as a collaborative research project? I am using coolcalc.

The structure is a 1-bedroom, 1-bathroom bungalow-style cabin with a 10:12 pitch, and with its single bedroom in a 4:12-pitch dormer. There is currently an open loft opposite the bedroom overlooking the living room.

It is orientated toward the South with significant glazing on that elevation. The addition continues to the East with more of a South-biased glazing.

The addition will be T-studs with dense-packed insulation (cellulose or BIBs, haven’t decided yet) with 2″ of GPS foam on the exterior. The GPS will continue onto the new structure, which is 2×6 conventional framing with R-21 bats.

The original ceiling is all cathedral vaulted. It has 14″ I-joists with R-50 cellulose. The new structure will be energy heeled trusses with R-60 cellulose.

Roof will be light gray steel and siding will also be steel (with a rain screen).

We are near Two Harbors, MN, so Climate zone 7.

Anyone up for assisting?


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