Moisture issue with improperly dense packed ceiling?
有没有人知道在未经辩护的拱形天花板中发生的水分问题的可能性是什么，其中纤维素绝缘不与屋顶护套接触？房屋位于寒冷的气候（纽约），在铆接天花板下部的纤维素绝缘和屋顶护套之间的空气空间之间有1到3英寸之间的任何位置（如通过钻孔的检查孔所观察到在外部拱腹中），而天花板的较高部分中的纤维素似乎完全填充椽腔。只是想知道它有多大或不太可能在具有不充分纤维素密度的区域形成凝结的可能性或不太可能。有什么想法吗？
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答复
The notion that "condensation will form" is technically inaccurate- both the wood and the cellulose will adsorb the water directly, and liquid water would only become evident after they become saturated.
你在纽约哪儿？得到了一个邮政编码？纽约国家涵盖了相当多的气候区和气候事项。
屋顶甲板材料类型（OSB？船圈镀膜？）和饰面屋顶型/颜色。
Dense packed cellulose is not sufficiently air-impermeable even at 4lbs density to keep wintertime moisture from migrating to the roof decking and would constitute a code violation. But whether it's a real problem that needs to be addressed immediately kinda depends.
Cellulose can handle quite a bit of moisture by itself without losing function, and by buffering that moisture it is protective of the roof deck. But high seasonal moisture cycling is also what causes cellulose to settle, which may be why you're able to find sections where it no longer fills the cavity. At a specified moisture cycling level it's possible to define a density at which it won't settle, but in a roof assembly in US climate zone 6 that density is probably higher than most blowing machines can execute. Most installers run it to 3.5-4lbs and call it a day, which may work fine even for a decade in an unvented roof, but probably not a century.
IIF我们可以确定它不在紧急列表中，长期解决方案是在屋顶甲板的外侧添加IRC - 规范的刚性泡沫，为您的美国气候区进行重新屋顶，以及顶部当发生时，通过从外部钻出纤维素。
http://publicecodes.cyberregs.com/icod/irc/2012/icod_irc_2012_8_sec006.htm
但是告诉我们更多关于屋顶装配 - 纤维素，内部饰面（包括涂料）的类型有多大厚度，气密是内饰，任何蒸汽延迟器/障碍等。
Bill,
This type of insulation doesn't meet code. If you want to insulate a cathedral ceiling with cellulose, the code requires a ventilation channel between the top of the insulation and the sheathing, from the soffit to the ridge. You need a baffle to create this channel.
无论您是否会获得潮湿问题，这误差取决于许多因素，包括（a）您的上限是否密封，以及（b）您房屋的相对湿度水平。（较低的RH比高RH更好。）
嗨Dana。我在气候区5.屋顶装饰似乎是1x6舌和沟槽，用建筑沥青瓦片（Foxhollow灰色）。椽子是2x8，在纤维素下面有相当多的旧BATT玻璃纤维绝缘。内部是全部1/2英寸的Speetrock，两层本杰明莫尔·富豪经典（100％丙烯酸）施用于墙壁和天花板大约三年前。房间里的木牌壁炉有拱形天花板，家里（建于1957年），所有新的节能窗和门都相对空气。拱形天花板的底部终止于2'外部拱门中，并且从外墙护套之间有很多空气泄漏到拱门中。顶板。拱门本身也在屋顶护套和面板的顶部边缘之间漏水。我还能告诉你什么？
Hi Bill. That's an interesting point. Would you happen to know whether or not the insulation contractor that installed the cellulose could be held liable for the error? This was a retrofit installation and a building permit was never obtained.
The air leakage on the interior side is moving the lions share of moisture into the space, and probably what is causing the cellulose to moisture-cycle to the point of settling, despite being nominally dense-packed.
内部丙烯酸涂料足够蒸汽可渗透，以免产生水分疏水阀，但是型号蒸气滞（两者都很好）。如果有任何方法可以更好地空气密封内部，它将降低问题的风险入门。
Plank sheathing is a lot more tolerant of this situation than OSB, which would more than likely would have already turned into a mold-farm. If you can, snake a flexible inspection camera into your peep holes and assess whether mold/mildew is getting started on the decking and report back. If it still looks pretty good, you may have years before any real problems get going.
灰色建筑带状疱疹，您可以获得高于每日高温（即使在冬季的屋顶温度）的体积，这也是有点保护的，因为它将水分送入易感木材。最容易受影响的间距将是阴影和朝下的部分，从而越来越少的太阳能增益，因此如果您还没有，那将是评估的更关键的部分。即使在这种非代码类型的安装中，南方的球场也可以非常强大。
FWIW: National Fiber (a regional cellulose insulation manufacturer in MA) swears by and will warranty dense-packed cathedral ceilings if installed by one of their approved contractors, even in US climate zone 6, (but I still wouldn't do it.) If you're on the warm edge of zone 5 the risks are much lower than on the cool edge of zone 6.