Vapor-permeable air sealing for cripple walls
In a 1930 stucco home in earthquake country, some seismic strengthening measures will go in in this winter, including plywood shear walls to cover some cripple walls in a 3-foot crawlspace. First I want to air seal the cripple walls that will be behind the plywood. The air seal must be vapor permeable. I’m leaning toward use of either kraft paper or a smart vapor retarder. I’m inclinded to lay the air seal against the outer wall, then bolts/holddowns, then mineral wool batts in the cavities, and then the plywood. The cavities might be inaccessible for decades.
哪种蒸气延迟？纸张（如牛皮纸或DB +）VS聚合物气相滞后（如Intello Plus或膜）？或者如果有人认为我应该抛弃连续密封和密封木头的想法而不是填缝或有限的泡沫珠(edit: or tape, see below)，也许他们可以说原因。
关于蒸汽迟钝的人烦恼我的一件事是关于“夏季”湿度的制造商备注。在我的气候区湿度是一年的回合问题。这些产品是否会在冬季日出时期为45度的90％的湿度来完成工作？
气候区3 c,粉刷外墙,斯图背后的纸cco from 1930 is fine but it’s paper, yes wind and sun both drive exterior moisture into walls in any season, yes there are interior sources of humidity in any season, no there is no capillary break in the footing. No inspector, contractor, or anyone else is going to be OK with impermeable anything in this location.(Edit: I mean not behind a shear wall. Foam’s great where appropriate. Also moisture is probably piggy backing on air leaks. Also there are flashing defects typical of the period. Despite almost a century of this the engineer seems to have found no need for remediating framing and it’s good to go for voluntary strengthening.)
GBA详细资料库
由气候和房屋部件组织的一千个建筑细节的集合
答复
为什么不胶合胶合板并用它作为空中障碍？
胶合板将有洞，用于白蚁检查，也许是其他检查。我自己通过类似的洞使用了一个胸腔，看看螺栓。我想到了这样做，就像你描述但制作膜一样可拆卸。似乎有点IFFY要做那样，它将希望在建造检查员身上不享用。
I also have a vague idea that sealing outside air out at the first opportunity to keep it out (interior side of the the house sheathing 1x6s) is better than letting it seep into the cripple wall cavity.
除了但不是不是密封护套之后，我也可能覆盖成品剪力墙，易于更换牛皮纸。至少现在我仍然认为这个问题是如何密封护套的内侧，而不是是否。
David,
Craft-paper is a terrible air-barrier - and isn't accepted as such under my code I know of.
Hi David.
这听起来像你实际上没有寻找蒸汽迟钝的迟钝，但只是一个空中障碍。那是对的吗？
If so, the first thing that comes to mind is a vapor open housewrap. They are typically known to be difficult to detail as an air barrier, but that is because of all the seams and fasteners. The materials themself do block air flow. You'd be able to use a continuous piece, will only need to determine how to seal the perimeter (probably an air sealing tape) and you won't need to punch a bunch of holes in it.
Brian - 是的，空中障碍，究竟。这只是我之前从未听说过汽室的材料，声音完全正确。我错误地猜到了蒸汽延迟器，因为它得到了渗透性。如果我没有Google的魔法搜索词，我就会错过很多东西。但是，在思想中，GBA已经写了那些房屋包装通常不是空中障碍。我没有解开。
Now I see that even Tyvek is considered vapor-open (I had no idea) and there are plenty of other choices. Also now I see Home Depot is advertising dirt-cheap asphalt-impregnated kraft D paper for precisely my application. Need to pick a reasonably economical one that can tolerate occasional damp at bottom (no capilary break, and at least for now no stucco flashing at grade though I keep hoping some skilled person needs a small job sometimes). Reduced environmental impact of the material itself is potentially a factor. I'm not expecting any need for bulk water to drain so that's not a factor.
至于详细信息，我的肠道是与每个木头关节的填缝或泡沫珠子或磁带相比的努力和少量相同，尽管我会发现，我不会想到关于房屋包装是否可以空气密封的问题，也许我仍然必须看看录像带。也许一些材料比其他材料更难细节。任何进一步的建议都欢迎。
你有大卫。Tyvek是最蒸气开放的建筑材料之一。作为一种材料，Tyvek和其他家庭包裹不允许空气通过它们。它是一个大型和复杂的墙壁上的安装，使其空气障碍差。思考损害空气密封性的所有接缝，过渡，紧固件和其他细节。在你的情况下，如果你可以安装一个长度并在边缘周围使用一些优质的空气密封胶带，而不是穿透材料，或细节很好地渗透，它应该效果很好，我想。