Feedback on Shallow Frost-Protected Slab Design
Hi All,
Here in far northern Maine, my options for getting pre-formed foam for a monolithic slab (warmform, legalett) are a bit limited (by cost of shipping, and well.. by cost in the first place.) In addition, none of the off the shelf products I’ve seen have seemed ideal for supporting a double stud wall. I was thinking about using standard ICF forms (nudura taper-top) glued down to dense foam as shown in the attached image. The inner 2×6 wall would be the load bearing wall, and I’ve included ties between the concrete that would be poured into the ICF and the floor slab which would be done in a second pour. These ties would help prevent any potential rotation of the concrete supporting the outer studs. The benefits I see are:
1. Nudura ICF forms are carried by the local supplier.
2.我可以专注于让外墙直/水平等，而没有压力/并发症，使一切都适合单一整体倒。
3.底板和混凝土外圈之间的热断裂
4. Outer framing of the double-stud wall is supported, without a thick plinth of foam that would extend beyond wall sheathing.
Thoughts?
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Typically structural slabs are an engineered product, so you could run this by the engineer you are going to need to hire.
通过ICF的内壁分开的混凝土会使我紧张，通过泡沫跨越泡沫的关系不会提供剪切或差动运动的大量抵抗力。
缺乏对剪切力的抵抗是有道理的，但另一方面，我看不到它会走得太远。一旦表土从我的财产的那部分刮掉，泡沫下的碎石就会直接坐在壁架上。
I got the idea from here:https://passivedesign.org/supergrund.
The difference is the slab (with thickened edge) would support the load bearing wall, while the "ring beam" would only support the non-load bearing outer framing and sheathing. Engineering for the thickened edge slab seems pretty well established, and this is for a single story home.
无论如何，如果人们可以在它甚至到达那一点之前，我可以节省工程师的成本:)
At first glance, I like it. Depending on jurisdiction, you may need an engineer sign-off, as Plumb Bob mentioned. I'm not all that worried about the loads on the ICF & ties, as they're only taking the dead load of the outer stud & siding. You may/will see some differential settlement between the primary house loads crushing the foam differently than the outer stud on its ICF/foam foundation. That could rack windows and other elements that penetrate the wall, so plan accordingly.
这是1还是2的故事建设？如果2，是由二楼平台框架或ICF基础携带的上/外双螺栓吗？
This would be a no-no in termite country, but let's hope that northern Maine doesn't see termites too soon.....
单个故事。我正在打算“郊外”窗户，里面有大型盒具窗台。窗户本身在外部框架上几乎完全是完全的，因此任何机架都会影响内外框架之间的胶合板盒。
With climate change, everything is marching north, but I think termites still have a long trek to get up here :)
检查处理基础的代码的IRC部分。您将在级增厚边缘上找到板坯（大多数完全过度设计）的指导。还要检查浅霜保护基础的部分;此详细信息不会满足水平翼绝缘的所需深度，但与您的建筑官员的对话可能会产生一个非问题。
Thanks, I'll definitely check the guidance for depth, thickness, and width of the wing insulation. I imagine I can lower it at least to butt up against the bottom layer of underslab insulation.
你有没有购物地泡沫？也许租一个u-haul并拿起它。
如果您包括ICF块，我认为使用更广泛的ICF形式在标准脚踏板上更简单，直接在ICF上携带。无需特殊工程。
For a single story you can probably skip the footings if you go with 10" or 12" core. Might have to increase the wall spacing a bit to make it work.