Is this what dense-packed cellulose is supposed to look like?
托尼菲尔|发布了GBA Pro Help在
Hi all,
我对其他人的意见感兴趣。我支付了一个绝缘承包商来密集一个在我家中的一个不经过者在我家中的一个不经过2年前的拱形天花板。在过去的一个月左右，我开始体验一些非常糟糕的水分问题。房屋内的片状缝的几个接缝开始在天花板上展示，即使在太阳出局时，即使在太阳出来时也会滴落。
在过去的周末，我在外部拱门中钻了几个3“圆孔，检查了椽子蛀牙，令人震惊的是那里的纤维素绝缘。我附上了一份照片的副本，我通过将我的手机通过其中一个孔粘上。绝缘承包商表示，它看起来像那里的原因是没有非常多的纤维素，因为水分可能导致它随时间稳定。
Is this really what dense-packed cellulose would look like if it got wet and settled? Incidentally, this particular rafter cavity doesn’t appear to have any moisture problems.
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Not a great photo, but from what I see it just looks like an under-filled space, not dense pack that has settled.
来自的水分问题来自哪里？就我而言，陪审团是根据您的气候区和其他一些因素可靠地包装一个不经常装箱的屋顶。
实际上，我认为这更准确地说陪审团回来并裁定你不能可靠地密集和不经常的屋顶。这是一些阅读材料：http://www.buildingscience.com/documents/reports/rr-1001-moisture-safe-unvented-wood-roof-systems
感谢您分享研究大卫的分享。正如我记得的那样，安装人员没有尝试空气密封任何东西，这可能是问题的一部分。我知道外部剖腹产泄漏的事实是因为在安装纤维素期间绝缘在整个地方射出接缝。我还有一个卫生气管道，通过从未密封的天花板的一部分垂直，所以我想也可能是水分也可能进入那里。希望我知道我现在知道的空气密封！
Dense-packing a cathedralized ceiling in cooler climates still comes with some risks, but the risk is pretty low in US climate zones 1-3 where wintertime roof deck temps are higher, with lower adsorption of humidity from the interior air. The risk is highest on north pitches with OSB sheathing, since the average temp of the roof deck is then cooler (taking on and retaining more moisture, on average), and the material (OSB) is the most-susceptible to moisture damage & rot. For t & g or ship-lap roof decking the risk is quite a bit lower, with plywood somewhere in-between. Straube's WUFI simulations in RR-1001 show near-zero risk for the cellulose insulated assemblies with OSB roof decking in zone 3 & lower, but substantial risk in zone 4 & higher. But only (the most susceptible) OSB clad assemblies were simulated. The picture here shows (the least-susceptible) plank decking.
That doesn't look like dense pack. At 3+ lbs density pushing on it with a finger is like a firm to very firm mattress- it'll be quite springy and it takes signficant push to penetrate it with your whole finger. At <2.5lbs density you can just jam a finger in it with fairly minimal resistance.
Cellulose settling is a function of both density and seasonal humidity changes. If it's cycling a lot of moisture in/out of the material there will be mechanical creepage and it'll lose some loft over time, but for any given climate & moisture conditions there is a definable density above which it simply won't settle. (This was modeled and tested very carefully by a researcher at Aalborg University in Denmark named Torben Valdbjørn Rasmussen- some of his academic stuff on the subject are available online in English, if you really care about the details.) If this was truly dense-packed it would take several years or even decades to settle appreciably, unless it's getting massively soaked somehow. (Ice dams backing up, soaking the roof deck & cellulose, mayhaps? Roof leaks?)
如果纤维素不充分致密，内部侧面是气密的，则可能存在储存在屋顶甲板和纤维素中的大量季节性水分，但它必须完全饱和，仍然在晚期发生滴水七月。可能有一个小屋顶泄漏饱和纤维素的一些部分，但由于纤维素被重新分配，因此在房屋内部滴入没有。
这是非常有帮助的达娜。拱形天花板面向东北部。雨水可以通过屋顶护套和扶手板之间的接缝中的一个通过表面张力进入外部拱道。由于缝隙填充有纤维素，可能存在一定量的芯吸，但是线路上面的天花板升起了一个好的5'，距离拱门开始并赋予屋顶的间距，它似乎重力会赢得邪恶。您是否碰巧对填充外部缝隙填充物的优点/缺点？据推测，安装人员这样做是因为在阁楼中从上面填充椽子湾比打开拱门，并从下面填充海湾，并在墙板上安装阻挡。但是，我忍不住认为，我遇到的一些水分问题与泄漏的拱门有关。
Tony,
David and Dana have given you good feedback. Here are my reactions:
1. That is not a dense-pack job.
2.除非您还包括绝缘材料顶部和屋顶护套之间的通风通道，否则您永远不应该尝试密集大教堂天花板。用纤维素绝缘不经过辩护的大教堂天花板是违规的代码。
也就是说，Dana可能会纠正你有屋顶泄漏。如果您认为您的天花板泄漏空气，您有一系列您需要处理的问题。修复你的屋顶泄漏（如果你有一个）。当您决定如何将您的天花板隔离时，以绝缘工作的一部分解决您的天花板中的任何空气泄漏。
More information here:
How to Build an Insulated Cathedral Ceiling
How to Install Cellulose Insulation