大教堂天花板绝缘（有些局限）
Hello, This is my first post on GBA. I am currently employed at a building department, and am constantly trying to learn. Anyways, I just bought a house and one of the rooms has a vaulted ceiling with 4×7 (actual) beams and 1.25″ sheathing. it currently has about an inch of foam on top of the sheathing, which is not enough… thus my problem. I want to keep the beams visible, which means I have about 6 inches to play with. I cant put more foam on top because the roof elevation of the vaulted room currently matches the rest of the structure, which is trussed. so my thought is to put 2″ of rigid foam up against the interior side of the roof sheathing and then get the rest of my insulation with a fiberglass batt. and then remove the 1″ of foam on the exterior and replace it with furring strips as to allow a for a 1″ of airspace and a “dry to the outside assembly” is this a recipe for disaster? I am afraid of moisture reaching the bottom of the sheathing and condensing and not being able to dry with a 1.25″ thick piece of sheathing between it and the air space. but the system seems similar to the r-zip sheathing assemblies that are going up on walls.
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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
I see no problems adding a vent channel as you describe, as long as you don't have an extremely low-pitch roof that would limit that vent channel's effectiveness.
Rigid foam on the inside directly against the sheathing is "cut and cobble", which is usually not a good idea with a roof, but in your case the ventilation channel makes it much less risky. The issue is that the perimeter seal around the rigid foam panels can't be trusted in the long term, so you risk some moisture making it to the underside of the sheathing. I think you'll have enough drying potential with the vent channel provided that you don't have a very low-slope roof, you have proper in and out venting for each vent channel, and you don't have a fully adhered membrane or other vapor barrier type of coating on the upper side of the roof sheathing that is exposed to the vent channel.
墙壁与屋顶有所不同，并且有点不太关键。您可以在屋顶的更极端的“顶部与蓬松的蓬松”比率中看到这一点，而不是“壁外的刚性外部与蓬松的内部”隔热层的比率。
Bill
Hi AFriesen11! I am a brand new, first time builder who is trying to learn as much as I can about construction while building my own 8x10 tiny cabin here in Vermont. This is the first time I am posting to try and help another person - so please take my response in that context (inexperienced and learning).
分享您所在的气候区可能会有所帮助。如果您熟悉气候区，我只是在这里了解到它们：//m.etiketa4.com/article/all-about-climate-zones
根据我的理解，如果您想将泡沫放在护套的内侧，您很聪明地取出外部泡沫，因为您不想在护套的两侧泡沫，因为它会捕获水分（我肯定您已经知道已经知道根据您的计划）。听起来您想更换1英寸的外部泡沫，如果我的房屋头上的图像正确，那应该有助于防止热桥梁，并在横梁之间安装隔热材料（泡沫和玻璃纤维），并使用切割和鹅卵石安装在梁之间方法。我不足以对两个设置进行完整的墙壁分析，但可能值得一看，根据您的气候区域，泡沫的1英寸是否足以保持护套如果添加几英寸玻璃纤维在护套的内部 - 这可能会使您的整体设置更温暖，而不是除去外部泡沫（如果连续），并用切割和鹅卵石的碎片代替它，这些碎片会在设置中重新引入热桥。您可能想在玻璃纤维的两侧添加空气屏障，如果您保持外部泡沫不应为poly，但可以在室内护套和干墙上贴上胶带。您可以使用本文中的信息做出确定：//m.etiketa4.com/article/combining-exterior-rigid-foam-with-fluffy-gusnation
我希望这很有帮助 - 如果没有其他帮助，它可以帮助我思考IVE到目前为止在本网站上学到的知识！
埃文
我已经附上了PDF，以更加清晰。屋顶是4/12，位于俄勒冈州中部5气候区。我会在FACIA安装山脊通风口和某种通风孔。我所有的屋顶膜都在空间上方。我知道喷雾泡沫是最简单的选择，但是由于费用，我试图远离它。据我了解，外部绝缘层不会使我的护套从露点中脱颖而出，因此是一种风险，没有任何清晰的干燥途径。还有其他组件可以起作用吗？