Retrofitting an Attic
你好。长期读者,第一次发布!
We bought a 1993-built house in Fayetteville, AR (Zone 4a, also ~1500ft elevation if that matters). It has a very steep gable roof with two east-facing dormers that serve as the windows of the master bedroom upstairs.
作为检查的一部分,我们发现:
1) Roof is not ridge vented, but there are a couple gable vents and I believe soffit vents. There does not seem to be any condensation issues from what we can tell.
2) Bathrooms are venting INTO the attic.
3)两个HVAC单元之一是阁楼。它是房屋原始的,我们选择更换它。目前燃气炉。
4) Original blow-in insulation isn’t great, and could also stand replacing.
在这里潜伏了很长一段时间之后,我的一般偏好是将阁楼带入房屋的信封并购买电力供电的HVAC系统(也许是热泵?)来代替当前的HVAC系统。我渴望摆脱整个房屋使用天然气,并看到这是一个千载难逢的机会,可以使用阁楼中的HVAC系统来做到这一点。
除非采用更好的方法,否则我们将在屋顶上打孔。
Last, and most pressing, concern here is insulation/encapsulation. It’s hard to suss out the appropriate recommendation about this as I read through older to newer articles here. I know sometimes roof line plays a role. What would make sense with the gable roof with the two dormers?
I initially got quotes for spray foam, but after reading some more, I have a bit of concern about the safety it, as I have small children (2yo & 5yo). Perhaps unfounded, but I’m not opposed to this if there is little risk and it is our only option.
谢谢,
- 肯尼
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答复
我假设您无法将HVAC设备从阁楼中移出,如果可能的话,这将是理想的选择。有很多理由避免在阁楼上安装任何HVAC设备。如果您想避免天然气,请确保使用某种形式的热泵。对于大多数气体,对于总能源消耗或燃料,电阻并不是对天然气的改善。
If you keep the attic vented, a ridge vent is more efficient than gable vents, but gable vents can work. If you put on a new roof at some point, I would absolutely install a ridge vent at that time, and be sure to use a proper ridge vent and not one of the "shingle over a piece of foam" type "vents".
如果喷雾泡沫是由主管安装程序安装的,则非常安全。人们通常会遇到缺乏经验的安装程序的问题,这些安装程序在喷涂时会弄乱混合物,这可能会导致不当治愈的喷雾泡沫,而这是“无权固化的”部分,诸如持久气味之类的问题来自。喷雾泡沫可能是封装阁楼的最常见方法,但这并不总是唯一的方法。
You mention you have a "steep" attic. How steep is "steep"? Could you possible frame out a small mechanical room in there? If you could, you could seal up that room and leave the rest of the attic vented (taking care to keep the ductwork inside the building envelope as much as possible). If you go this route, you could use rigid foam and batts for insulation, avoiding the use of spray foam.
Bill
Thanks for the advice. I am exploring the idea of getting a room built, yes. We've just had issue getting access, so I'm not entirely sure how much space is up there. I might put a pause on all this until I can really examine things.
绝缘屋顶护套的外部是否是更好的方法(考虑到我们在未来5 - 10年内可能需要更换屋顶)?我读过这是一个很好的方法,但不知道那里要考虑什么。我想找到一个合格的安装程序可能是其中最重要的部分。
如果可能的话,请考虑撤消很久以前有人将HVAC放入阁楼上的非常糟糕的选择。想想迷你拆分和壁头。
If that seems impossible consider that gable wall plus the roof sheeting may have double the surface area of the attic floor. This surface area will likely loose more than twice as much energy as a well-insulated attic floor simply because almost no one will spend the money to put up R60 spray foam over that vast area given its high cost. Almost anyone can spread R60 on the attic floor with the free blower Home Depo will provide.
有条件的阁楼只是对当前情况的边缘改善,因为它的表面积较大,而R值较低,如果管道紧绷并且旧的绝缘材料较厚,则可能会向后倒退。
摆脱燃气表及其20美元左右的月费可能是一个好主意,但主要与您的本地费率计划有关。通常,如果天然气是来自管道网络的城市气体,它的成本如此之低摆脱它并不具有财务或舒适性,但是倾倒丙烷几乎没有任何脑袋。
我敢肯定,大多数喷雾泡沫安装都很好,但是事实是每隔几个月就会有一个可怜的灵魂发布一个恐怖的故事,我们从未听说过纤维素绝缘的问题。
Walta
+1
Oh wow I never thought of it that way. Amazing advice.
Also, for me, getting rid of gas is a health/sustainability measure. I would like to one day be fully self-powered with solar and other renewables. Not as concerned about that $20/mo either, but a token reward for achieving that goal, I suppose :)
如果您有2x4桁架,在地板上喷R60仍然有意义吗?我试图弄清楚如何修复阁楼 - 天花板上的盒子和4英寸绝缘的盒子没有空中密封,楼上所有的管道都在那里。我觉得如果我将其提高到最低限度(塞勒姆俄勒冈州,所以我认为R-38)很难再去那里进行维护,检查屋顶或从阁楼上做任何形式的改进。
Alex I do not think they can spray R60 and follow the manufactures instructions because it would be too thick even if it was possible no one that does math would do it because the foam is so expensive no one could live long enough to get a return on that investment.
“超级硬”是某些人无法修剪自己的手指指甲和其他100英里泥泞的障碍赛的观点,这一天很有趣。在充满绝缘的阁楼上工作是可能的,但不愉快。
Walta
我同意一种普遍的意识,即空气密封和绝缘是要走的路,而将HVAC移入信封内。但是,我想更好地了解主卧室窗户配置,以对此有具体的建议。
至于沐浴风扇的通风口,它们可以从山墙末端或屋顶上走出。如果山墙端不远,山墙的末端会更容易。