Closed-cell spray foam roofing?
I’m finally having the suspended concrete floor sprayed underneath with closed cell foam. It has been a fight to keep the space comfortably heated while the floor would remain around 40 degrees Fahrenheit.
发言给小公司的所有者向我提供这项服务，他说他在他必须密封它的生锈锡屋顶上使用了封闭的电池泡沫。他说他使用了某种类型的涂层来防止紫外线导致它恶化。他说他在外部做了其他屋顶，似乎工作得很好。我非常满意他在我的浮动板上所做的事情，但我不确定他在这些屋顶上做了正确的事情。我生活的大问题是找到真正确实知道他们在谈论的人的人。要诚实，这是一个专业人士的艰难地区，因为它是一个具有较低收入人群的农村地区。
Ive checked online and found that this is done on flat roofs. I have a flat roofed building that has the rubber membrane and is close to needing replaced. Is this something I should consider doing? I don’t think the fellow I mentioned uses anything special for his roof coatings so I would contact someone else for this service or buy the equipment and start doing it myself.
What do you guys think about this system, it’s pros, cons?
Thanks in advance. Barry
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Almost all 3lb density polyurethane foam roofing is blown with HFC blowing agents (soon to be banned under the Kigali amendment to the Montreal Protocol), that are extremely powerful green house gases. Three pound foam also has a very high polymer per R as an insulating material.
在加侧，它确实很好地密封，如果从紫外线保护持续很长时间，它就是移位其他，更临时的屋顶材料。它如何相对于其他屋顶在生命周期物质基础上工作取决于它的维护程度。在平顶屋顶使用石头镇流器，因为非常耐用的紫外线保护器在需要拆除雪载的地方不存在。
如果进入这条路线，使用在屋顶甲板上实现露点控制所需的最小金额，（如表R806.5在IRC中的冷凝控制中所概述的），具有开放式电池泡沫或纤维绝缘效果效果屋顶甲板的底部是“绿色”的方式。单一英寸的喷雾屋顶聚氨酯（~R7）使用多种聚合物为6英寸的开放式电池泡沫（R22）。与屋顶聚氨酯不同，开放式电池泡沫吹入H2O（水），非常低的冲击发泡剂。
https://up.codes/viewer/utah/irc-2015/chapter/8/roof-ceiling-construction#R806.5
I believe under the roof deck is 2x6 or possibly 2x8 rafters, wooden lath strips, plaster then a drop ceiling with insulation batts on top of it. I don't know if that would cause any moisture problems? I'm really just interested in the roof covering but figured if I could get any r value it would be a bonus. This rubber membrane roofing hasn't lasted very long at all. Ten years at tops. Without talking to a professional I'm not sure what's next, patching or replacement?
More information is needed to make this call. Your location/climate zone matters, as does the ventilation (if any) to the outdoors in the space between the drop ceiling batts and the roof deck.
Insulating on top of a vented roof doesn't usually add a lot of thermal performance.
I'm around 3000 feet elevation in the North Carolina mountains. I'm not sure what's zone that is. It gets cold here and we get snow but super rare for it to be heavy enough to need to remove it. I doubt it's ever been removed but I'm not 100% sure.
I'd guess if there's any ventilation it's unintentional as I've seen nothing protruding through the deck.
Barry,
Here are links to two articles with more information:
"Spraying Polyurethane Foam Over an Existing Roof"
"Roofing With Foam"