喷雾泡沫阁楼：在需要的屋檐上阻塞吗？
闭孔阁楼喷雾泡沫，气候4A，气球框架1924房屋，墙壁上的密集包装纤维素。当我试图在隔热材料之前准备阁楼时，我还试图对自己的一些细节进行自我教育，以便我能够在最终合同中阐明自己的偏好。通常，详细信息被遗漏并留给承包商。学习曲线陡峭的一部分是，如果您从未研究过木材框架或观察到房屋的框架近距离，那么很难形象地描绘出实际的布置方式。
我以为在去除现有的玻璃纤维绝缘材料之后，泡沫将一直延伸到包含的空间的边缘 - 超过顶板（两个双2x4，定义了房屋墙壁的边缘 - 进入我的边缘 -案例，一个相当浅的悬垂/拱形区域，在筋膜委员会结束。我的眼睛4-5英寸 - 我们有一个小的悬垂。
But from what I have learned on this site and others, blocking with various kinds of board is often applied–probably easier from the outside if it was open at the time–but that would also have to be covered from the inside with gypsum board or some other thermal barrier for fire protection. The two reasons this seems to be the case is a)the fascia board often has cracks in it from age or shrinkage, and if the foam is sprayed that far it will seep out the crack and possibly cause a huge mess that the contractor will have to clean up; b) the contractor doesn’t want to pay for the extra foam into the soffit area that is likely not necessary since it is outside the envelop of the building.
我们已经与之交谈的承包商 - 都不打算使用阻止。他们将删除大部分裸露的玻璃纤维（请参阅附件的照片），并可能打算将余额放在顶部板上以阻止。经验丰富的GC向我指出，绝缘材料永远不会被塞入这样的边缘，如果房屋没有那么开放，可能会导致由于水分积聚而导致腐烂。在我看来，一堆去除的玻璃纤维没有腐烂的迹象，只是几十年的冷和热的迹象。您可能看到的黑色是衬纸的碎片。
笔记the grey arrow in the diagram pointing to the same area as my photo shows.
所以我的问题是：
1-是使用旧绝缘材料作为阻塞吗？还是应该去除它以防止水分积聚等，然后将残留的灰尘抽空以使喷雾泡沫更大？
2散布的喷雾泡沫只能经过顶板的外边缘几英寸？
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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
David,
Your attic won't need ventilation once the spray foam is installed, because you are creating a conditioned attic. So you don't need ventilation baffles to allow air to flow from your soffit to your attic. This area can be foamed.
拱腹中的玻璃纤维绝缘是无害的，可以留在原地。它将很好地作为闭孔喷雾泡沫的备份。只需确保（1）您可以看到墙壁的顶板，以确保喷雾泡沫覆盖顶部板，（2）喷雾泡沫安装在足够厚的层中（例如，最小2至4英寸）在该区域的结构上足够强大，因此不用担心泡沫固化后泡沫会破裂。
- 马丁·霍拉迪（Martin Holladay）
Thanks Martin. Didn't mean to give the impression i was talking about ventilation baffles from soffit, just wondering what to do about any space between the end of the spray foam after the top plate and the soffit/fascia. Apparently leaving the insulation in between top plate--or just a little past--as blocking is ok. We decided to go R-38 which will be a little over 5 inches. We also are opting for the DC 315 coating for the thermal break instead of the sheetrock due to cost as well as thermal bridging as long as we can be assured that the DC 315 is approved for the assembly with the particular foam the contract will use. I had heard that that Demilec -made coating is an approved thermal barrier with Demilec spray foam but still trying to verify that's true with other foams as well.
承包商表示，他要么使用现有的绝缘材料作为挡住顶板的阻挡对通过裂缝可能发生的泡沫挤出责任负责。
我只是想对你说,顾问site how valuable this site is to homeowners especially when we are in the midst of researching and trying to make informed decisions--well worth the subscription price. GBA is really at the cutting edge of the emerging knowledge in this field, which seems to grow on a daily basis. Thanks for all the time you put in helping us out.