DerbyDad03 wrote:
....
Bottom line - if the "fix" will cost you more than an original plan
that dealt with the venting issue in the first, the engineer should
bear that cost.

I don't necessarily agree--if the engineer was only contracted to design
the structure and wasn't provided the other information, his
responsibility started and stopped w/ providing adequate construction
details compliant w/ local codes.

He can not be expected to compensate for conditions/constraints unknown
to him owing to that information having not been provided to him or
beyond the scope of his requested effort -- which it sounds like was the
structural design of a beam of sufficient strength and construction
detail for same. It would not be at all unreasonable for him to expect
the HVAC/vent/electrical/etc. was in the purvey of someone else given
his design for the cathedral ceiling structure.

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