Air seal and insulation for existing 100-year-old exterior walls
Wall assembly is (outside to in) … cedar clapboard, tar paper, pine board sheathing, 2×4 wall, lathe and plaster. IR scan confirms no insulation in the wall cavity. The walls will not be opened.
BSC teaches me that control layer priority is water, air, vapor, thermal. Lightbulb for me … air control is more important than thermal (R value).
So what to do with these old walls which have been doing their thing for 100 years? Would blown-in cellulose screw them up? Retain moisture in the wall, exterior paint lifting, rot, etc?
我正在考虑几个策略。
- 房子的机会，改善了这些旧墙壁的空气控制层。
– Blown in / dense pack mineral wool. Yes I did mean mineral wool … evidently it can be blown-in (though rarely discussed). Won’t absorb water, lets vapor pass to dry into the interior.
What do you think?
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您在哪个城市和州，您是否碰巧了解您的气候区？气候较冷，你必须越小心，避免拧紧你的建筑物的湿热动力学（换句话说，热量和水分流量的方式） - 而在流动性和不舒服的情况下，这种组装具有野兽干燥潜力。绝缘和空气密封通过降低组件可用的热量和空气来降低干燥电位。补救措施的复杂性将取决于与地理位置和气候的建筑物的风险程度。
Hi Wooba Goobaa.
Dense pack cellulose is probably the most common type of insulation used to retrofit homes like yours. Not only does dense pack cellulose add R-value, it also has some air sealing value. Unless you have leaks from bad flashings, fo example and the walls are getting excessively wet, you shouldn't have issues with dense pack cellulose. Check out this article:How to Install Cellulose Insulation
Many green builders also prefer cellulose because it is one of the more environmentally friendly options.
AeroBarrier brings a new option to the table. I have not seen any AeroBarrier work done in any very old houses yet, but would be interested to hear how effective it is in tightening up a home like yours.
Zone 5 Eastern MA.
Yup been up and down all the cellulose advice and warnings.
I'm contacting a few AeroBarrier service providers to see what they have to say. I think the house first needs to be brought to a minimum ACH before they will attempt it. NS Build did a piece on an older brick home that was not able to be insulated, but they had some success with AeroBarrier.
Does anyone on GBA have experience with blown mineral wool into old walls? I see American Rockwool offers a granular form.
>"Does anyone on GBA have experience with blown mineral wool into old walls? I see American Rockwool offers a granular form."
MA high performance home architect/builder Steve Baczek uses it from time to time:
https://www.finehomebuilding.com/2018/09/14/blown-mineral-wool-insulation
http://www.stevenbaczekarchitect.com/info/
我很长时间的商业合作伙伴改造了他19世纪初的牛顿的古董，吹岩羊毛，但这是〜40年前。它在很好的情况下举起 - 在寻找空旷的海湾才能充满纤维素的空白（窗户上方的几个短湾）时，在最近的偷看中没有定居，但是不能肯定是什么产品或者它是r价值的。
A few of the exterior walls have been opened. Unsurprisingly, some surprises revealed.
所有外部螺柱托架安装了沉重的纸空气（？）屏障。这将阻碍任何尝试将其他墙壁螺栓腔吹入外墙螺栓腔中。还注意到它已经潮湿的证据（我们打开的所有螺柱海湾的典型）...倾斜我往矿物羊毛与纤维素。
@Dana。为什么你的朋友用吹纤维素回到他吹岩羊毛改造？
Why not just insulate from the outside?
Meaning blow in from the outside? Same issue ... half the stud cavity is not accessible.