Thermal bridging via a steel I-beam in an exterior wall
We have a masonry row house building with interior insulation (about R16) in New York city. The exterior of the building consists of 3 wythes of brick (about 12″ thick). We are now building a steel frame deck. 2 steel i-beams will be inserted into the outermost wythe to support the deck. Does this present any kind of thermal bridging?
Note, the i-beam does not penetration the two innermost layers of brick npenetor the interior insulation. It only penetrates 4 ” or one brick width in.
I ask this question because I don’t really understand if the cold steel up against the brick actually presents more of thermal threat than the ambient air temperature.
Thanks.
Daniel
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Replies
Daniel,
I don't think that the steel beam you describe will affect the thermal performance of the wall very much.
Of course, you need to make sure that an engineer has approved of the plan, and that the beam is adequately supported, and able to transfer the load to a solid footing.
It's also possible that the beam you describe will cause water entry problems, depending on how it is flashed. But I wouldn't worry too much about the wall's thermal performance.