Basement walls
We are renovating our basement. We have a house constructed in 1929, with a rubble foundation. I have seen things like this: http://www.abtfoam.com/prefur.htm which you can attach sheetrock to directly. Does it really need a perfectly flat wall to do this? can you install this sort of thing against an uneven rubble wall? What do you do?
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对于瓦砾 /田野 /砖基础，通常最好修饰砂浆，然后将2-3英寸的闭孔泡沫安装到空气密封，隔离和水分密封基础，然后在其前面建造一个常规的未绝缘螺柱。
A co-worker did his uneven not-too-flat CMU basement wall last year by installing a 1.5" deep steel furring /stud framing about 3" in front of the foundation as a depth guide and installing 3" of HFO blown closed cell before installing the wallboard. Some rubble foundations are flat enough to use that approach, but very few fieldstone walls are.
当您不想使用喷雾泡沫时，解决方案是什么（刚性还可以），并且您也不想用框架墙壁浪费不必要的空间？（但是只希望它看起来更好）
Don't use EPS with a big cavity between it and the foundation- the potential fire spread issues are pretty severe.
Start with a serious round of mortar repair, and maybe even a sacrificial parge of lime mortar if there is a lot of efflorscence. Set an exterior-grade steel studwall as close to the foundation as possible, with a 0.75-1.5" continuous layer fire-rated polyiso on basement side, seams taped. Build your 2x4 fiber insulated wall tight to the polyiso, with a 1" layer of EPS under the bottom plate that is also under the cut edge of the polyiso to prevent potential moisture wicking. Ideally the R-value of the polyiso would be at least the amount sufficient for dew point control in your climate zone on a fully above-grade 2x4 wall.
The joist cavities above the steel studwall & gap will need an air sealed fire stop, and the joist bays need to be insulated as far inward toward the basement fully over the 2x4 top plate.
Thanks, When you say mortar repair, what do you mean?
Also we are in Zone 4A. We will be doing some exterior insulation on some of these walls..
>"When you say mortar repair, what do you mean?"
Rubble foundations are usually built with mortar between the chunks, not dry stacked. Over 90 years some of that mortar has likely fallen out or been degrade by efforescence, etc. Replacing any missing or compromised mortar should be done now, while it's still inspectable and do-able before boxing it off ne'er to be seen again until somebody guts the basement walls.
Right ok, otherwise known as repointing. That’s what I thought.