What wrap or spray insulation would be recommended for use on aluminum beams that will penetrate a building?
L. Walker| Posted inEnergy Efficiency and Durabilityon
Exploring building a cantilevered balcony using aluminum beams in order to fit the beams between existing floors. Looking for a material to prevent heat loss and condensation without corroding the beams.
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Replies
L. Walker,
Just say no to cantilevered balconies!
Good luck on solving the thermal conundrum... it's not easy...
It may not be easy or worth the trouble...but there are "ways"
One example.....if you look at the last photos in this gallery
https://sites.google.com/site/trekhauspdx/home/building-progress/building-progress-3-august-2011
Martin as usual is spot-on. Cantilever penetrations of the building wall should be considered a no-no for several very good reasons - in any case aluminum would be a poor choice because of its high thermal conductivity and non-optimal structural performance.
The trekhaus balconies are a good alternative to a cantilever, but if you have no building projections to take advantage of you could have your balcony designed as a self-supporting unit using the balustrades on each side as suspension brackets. Either way you'd still have minor structural fixings through the WRB but these would be no more than for a typical deck, and easily managed.
In the middle of repairing a cantilever deck. never flashed well, and is not easy to flash period. After 20 years the garage door headers rotted completely away under this deck.
I used angled back posts on the last deck that the owners didn't want straight down posts.