wind and r-value
rjspotter
| Posted in Energy Efficiency and Durability on
I live in a place with significant wind, Cheyenne Wyoming. The wind, pretty consistently, comes from the west northwest. I’m doing a remodel on the northwest corner of the house. I have a brick facade but I’m redoing the insulation inside. Does it make any sense to do higher R-value in the walls facing the prevailing winds?
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Replies
The wind increasing the need for good air sealing more than it increases the required R-value. But if there's a good way to bump up the r-value every where, that's good too.
+1 for air sealing as a priority in a high-wind location!
What wind does is stip away the static air film on the exterior, which costs you maybe R1 or so. Aside from that, wind doesn't do anything to make your insulation R value any different than it would normally be. What wind DOES do is push higher air pressure against all the surfaces, which will make any air leaks leak even MORE air -- that's why air sealing is more important here!
Insulation does always help though with overall heat loss. I would try to get some continous insulation into your assembly if possible (the brick facade complicates things here), which will help to cut down on thermal bridging of the studs.
Bill
pjspotter,
Wind will increase the heat loss of a home - and improved air-sealing will help with that - but wind-washing of the insulation doesn't significantly decrease the R value of insulation in walls, so you don't need to add more in the ones facing the wind.
See tables 8 and 9 in this link: https://www.rdh.com/wp-content/uploads/2017/10/Van-Straaten-Windwashing.pdf