Insulating HSS Column in 2×6 Wall
Hey team,
We are in Zone 6 and our structural engineer is requiring 5 x 9 x 1/2″ HSS columns for a moment frame in one of our 2×6 walls and I was wondering how you recommend approaching insulation and/or issues of thermal bridging in this circumstance.
Thanks
Brad
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Replies
To get similar strength in the Y axis (the direction that usually matters most in a moment frame) you would need to go up to a 16x4x1/2" if you want a thinner assembly using tube steel. You could also ask your engineer if there is another shape such as a W-section that would work in a thinner space.
If you're in CZ6 you should have continuous insulation on the exterior anyway; a 2x6 wall alone is pretty skimpy by today's standards.
Thanks, Michael. We were considering going to a 2x8 wall so we could sandwich the column in rigid within the cavity, and then we are planning for Comfortboard on outside.
Brad, the Comfortboard is a thermal break, though more insulation is always better. You don't need to have insulation on the interior side of the steel if you have insulation on the exterior side. In fact it's best to keep all insulation toward the outside of the steel, to avoid condensation inside the column.
Thanks again Michael, this makes sense and I appreciate your input.