Got a friend (no, really) anyway. He wants to swap out a pair of windows in his walkout with an 8-0 6-8 slider. Easy enough. The red herring is, not a lot in the way of headroom. Lucky for him, he’s got a friend who’s an engineer, who did the load calculations for him and decided that in order not to exceed the 6″ he’s got for the header, he needs steel. Specifically, tube steel, rectangular, 3/8 sidewalls. This is fine, the thing is 3″x6″. He calls me and says basically hey, this all sounds great on paper, but from your perspective, i.e. making it work – anything missing? I think insulation pretty quick. You’ve got this big hunk of steel on an exterior wall providing a wonderful thermal bridge. All I can come up with in my head at the moment is 1/2 extruded poly – and that’s not much. 2×4 wall, so short of demoing the interior of the whole wall to fur it out (which isn’t a lousy idea) . . . any other great thoughts?
“If you pick up a starving dog and make him prosperous, he will not bite you. This is the principal difference between a dog and a man.” – Mark Twain
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Could you build out that beam in such a way that the door and casing would look good running up into it? Maybe take the beam build up the entire length of the wall. Short of furring the wall..........?
Remodeling Contractor just outside the Glass City.
Quittin' Time
man I feel your pain or should I say cold. If you can't a void it I would put the steel to the inside and try some foil faced which has more r value and the steel will stay warmer so you don't get shadows from the cold being 1/2 from the DW. And if you can open the ceiling DW and move the header into the rim joist area and go back to MIcrolams. just something to consider. Mike
Are the ends capped? You could fill it with some material. The thermal bridging around through the top and bottom would still be significant.
How about 3/4 polyiso. This has an eventual R value of about 6.5, then cap it with 1/4" SR. This R value would exceed any window in the house.
Which brings me to my final point. You're talking about 4 square feet here. Taken proportional to the rest of the house this is small potatoes.
Jon Blakemore