Thoughts on PERSIST construction in Chattanooga, zone 4a
我正在使用持久技术设计我的房屋，并希望对适合我气候区域的绝缘比率进行输入。我在4A气候区的查塔努加（Chattanooga），有3587个供暖天数和1544个冷却度天数。
Practically speaking, we have 3 months of trying to stay warm, and 8 months of desperately trying to stay cool.
我的计划是一个1200平方英尺的2层，扁平的房屋，带有简单的足迹，面向被动加热，窗户相应地放置。
我将OSB护套包裹在冰和水上保护区（包括屋顶）中，分层为3英寸的EPS以进行耗尽（R-15），然后是毛茸茸和金属壁板。2×4的墙壁将用1×6 T＆G板覆盖（没有干墙，没有腔体绝缘，这似乎是疯狂的）。
该基础是在混凝土茎壁上抬高的浮动板，所有板都隔热了2英寸硼酸盐处理的EP，并在泥石丘上进行了严重的细节。
The problem I’m having is an effective “case study” in my region with which to compare this to, and of the many questions I’m having, the issue of whether to insulate the cavities at all (given the R-values and lack of thermal bridging of the wall assembly I’ve described above), and whether my interior finish needs to be replaced with airtight drywall.
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由气候和房屋部分组织的一千个建筑细节的集合
答复
Myles,
You don't need airtight drywall, because the Ice & Water Shield is your air barrier.
三英寸的EP不会给您R-15；它将给您大约R-12。（也许您打算写XPS？）
Your proposed R-values are too low to meet minimum code requirements. In Climate Zone 4, the prescriptive requirements of the 2009 IRC call for a minimum of R-38 insulation in your ceiling. If you plan to use EPS, you will need about 10 inches of EPS on your roof.
马丁 - 谢谢，是的，那将是R-12的薄天花板！我计划将其加厚。
我的计划是使用EPS，并且我的逻辑或缺乏，是基于我阅读的有关其他泡沫的长期R值的文章，以及在偏远墙，SIPS，SIPS，SIPS，SIPS中使用的EP的照片和被动房屋。我愿意接受建议 - 箔纸面对的polyiso是亚军，
I'm still wondering how thick to outsulate before considering filling the cavities. For example, I would have a 50/50 inside/outside ratio with R-13 between the studs and 3" R-12 foam outside. The Alaskan formula for this ratio seems to be 1/3 inside, 2/3 outside, if any cavity insulation at all.
Since the PERSIST technique seems to be one of the most exportable wall assemblies (mentioned in your article) in terms of climate, my question is what ratios/ thicknesses would work safely in the sweaty South? If I use 4 inch EPS foam outside, I'm insulating at nearly the same levels as parts of Alaska, at least according to some of the REMOTE diagrams. I'm missing something here (besides an engineering degree!).
If you are considering a fully wrapped construction in zone 4, why consider inside insulation at all ?
我和recommen会很舒服ding you to use ~ 4" of EPS on exeterior walls
最多要达到平坦屋顶所需的一切（堆叠EPS，不要忘记在最后一层使用致密品种）
What is your coldest night temp during winter time? ( let's say coldest average for a few days , not a single peak )
I just completed insulating a "re-do" of a small 14X16' roof exit on my house, using mostl reclaimed 5" EPS . Plywood with peel-stick screwed on 2X4 framing onto which i installed from 6.5" to 10" of EPS ( 2 walls accessible on the roof received 2 layers of 5" of the EPS and the 2 exterior walls 1x5" + 1.5" of R4 EPS with glued on tyvek )
Will be using probably 2 stack of 5"EPS on the roof + 0.5" recover boards of iso before the EPDM .
As you have more heating than cooling EPS is probably a great choice, if you have a good cheap supply in your region.
If your temps are not extreme, you could use some thin FG bats inside stud bays maybe ?
取决于您的露点演算。
我可能会在胶合板表面内使用一些回收的1英寸EP，周围有一些条带。
4" EPS exterior is nothing overkill, unless you plan on using more insulation at the interior.
我的感受完全是将每股收益增厚到4英寸，而不是在这篇文章结尾处列出的犹豫。可用且负担得起，并接受了表演守卫的处理。这是我的最后一条防御方法，以多管齐下的方法使昆虫脱离结构。除了白蚁（我们处在福尔摩山白蚁的北向北行军的边缘）之外），我与飞行的蚂蚁，木匠蜜蜂，黄蜂，蟑螂，洞穴板球和黑寡妇进行战斗 - 其中一些是侵扰的，因此昆虫的管理是壳的驱动因素。保持建筑物的干燥显然可以防止吸引他们的条件因此，在关键的，极其难以接近的位置，冰和水盾是廉价的保险。但是，如果没有泡沫板，我会担心使用它。因此，整个持久套餐，全部或没有 - 但没有用于调整它的数据到这个区域。
冬季夜间的温度在三十多岁，浸入单位数字4到6周，这取决于（今年是冷的），但这里的主要努力是防止潮湿的热量。肩部季节似乎正在消失。
Detailing at the stemwall/ mudsill junction is making it difficult to push exterior foamboard thicknesses past 3 inches, which I'm having a hard time resolving. Getting full plate bearing over the stemwall, providing a ledge for the slab edge, insulating and termite-proofing the slab edge, working a termite shield in there, providing an opening for the rainscreen while denying access to insects, and water/air proofing the whole shooting match is daunting and no diagram online has completely solved it. In addition, without unnecessarily insulating the exterior of my stemwall to the same thickness of the structure above, I'm out of plane and have an aesthetic issue. Thank goodness for Sketchup- I've made a lot of models of this area, but still, no dice.