新的附属建筑，霉菌，爬网封装/通风计划
I’m building a 190sf art studio/office in Zone 5B (Central Oregon, drier/sunnier eastern side of Cascade range, sandy/volcanic ash soil, 24″ frost line, ground freezes here). It has a one-year-old vented crawl space that developed mold beneath the plywood subfloor and I-joists. It sat with no roof and no ground moisture barrier through last year’s snowy winter. Last Spring, I scrubbed the mold off with diluted bleach and spread 6mil poly over the ground, but did not attach the poly to the stem wall or seal up the vents.
一年后，它已关闭，空缺，无隔离，没有干墙，基础仍在发泄。霉菌已重新出现在爬行空间中，并且在上面的地板螺柱上看到了一些，内部OSB墙壁护套以及Tji afters的上方有些。我认为我的水分问题是由于地面，茎壁本身以及四个粉底通风孔造成的。没有雨水泄漏，因为我仍然可以看到所有框架。爬网空间当前平均为35°，RH为65％。外面是45°和30％RH。水分表读取15-18％。
Interior plans:
墙壁 - R21面对FG Batts。
大教堂天花板 - R30未透明的FG Batts带空气建造的2英寸通风通道（具有鸟块通风孔和全山脊通风口）。
Floor – Was to be fg batts in the joists but, if I’m on the right track, I should change that to XPS/EPS on the interior foundation stem wall and also cut and cobbled into the rim joist.
Drywall – Airtight method.
HVAC - 没有炉子/交流电或HRV/ERV的计划。
As this isn’t a house, I’m less concerned with R-value efficiency/human comfort as I am with affordably solving the moisture issues. Ideally I’ll be able to leave this building unattended, without constant conditioning, only heating with a space heater as needed when in-use. Rarely hot enough here to warrant AC, and it has plenty of operable windows. To exhaust oil painting art studio odors when I can’t open a window, I’ve planned a wall bath fan that exhausts directly out the 2×6 exterior wall (70 cfm, 0.1″ static pressure, DC motor rated for continuous use).
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1) Seeing as this is not a dwelling, is it still recommended to encapsulate/condition the crawl space?
2) For crawl space ventilation without HVAC, would the sensible choice be a floor-mounted air register along with an exhaust fan positioned over one existing foundation vent? Would it have to run constantly even when the building is not in-use? Is this necessary?
3) Will the crawl space exhaust fan conflict with the painting odor bath exhaust fan?
4）基础内部泡沫需要的厚度如何？R15？轮辋托梁中的R-Value，还是在靠近墙壁/R20的情况下撞到？
5）在大教堂的天花板中，在干墙和未透明板之间添加蒸气屏障（例如膜）是否明智？
—
在过去的几个月中，研究了我的天真和错误之后（在当地建造者朋友的老式建议“需要呼吸”的老式建议）中。建立科学令人着迷，谢谢大家的出色资源。
谢谢！
Kevin
GBA Detail Library
由气候和房屋部分组织的一千个建筑细节的集合
答复
对于天花板上的泡沫，对于更高的空气，首选岩石或高清玻璃纤维。
R30仍低于IECC 2015的最低商业建筑（除非在屋顶甲板上方连续绝缘）。如果HD38又名“ R38C”（用于大教堂的天花板）适合您的after子，请使用它们。有2x12铣削的afters和HD38的通风距离还剩下一个英寸，这已经足够了。
只要天花板的石膏是相当紧密的，就不需要在气候中比标准的乳胶天花板油漆更紧密，即使只有代码钟的屋顶甲板排气。
Unless it's going to be covered with an ignition barrier, use Dow Thermax rather than polystryene for the stemwall insulation. Tape the cut bottom edge with foil tape, and lap the ground vapor retarder up the stemwall, between the foam & foundation.
R15 would be needed for code on the stemwall if it were residential, but it only needs to be half that to meet IECC for commercial buildings. See Table C402.1.3:
https://codes.iccsafe.org/public/document/IECC2015/chapter-4-ce-commercial-energy-efficiency
1.5“ Polyiso的运行率约为R10，这使得它具有边距，但是您需要2英寸的EPS才能在基础墙上达到IECC 2015代码最小值。
谢谢，达娜。我需要达到商业建筑法规要求吗？这是对农村住宅物业的附属建筑，足够小，不需要我县的许可证。我不清楚这种建筑物的代码要求。
如果我呆在天花板上的R30未果FG（已经购买），我会冒着水分/凝结问题的风险吗？还是建筑物不会那么高效？
屋顶已经装有OSB护套，15＃毛毡，屋檐的冰/水上盾，沥青木瓦。我有12英寸的tji r徒。我确实担心两个山墙末端的rafter bay孔，因为有2x4的look望台紧紧地伸向OSB，握住耙子。修剪或只是压缩那些2x4所在的巴特。在这一点上，我认为这是我唯一的选择。
I read conflicting info on the ignition barrier somewhere saying it wasn't needed in a crawl space if under 36", which is about where mine is. What are my options here if I can't source the Dow Thermax?
Kevin
An outbuilding isn't like a residence, and the internal moisture sources & quantities will vary by use. If you're growing commercial weed you'll have a different moisture profile and energy use than if it's usually-unoccupied office, etc.
您的“需要”取决于本地法规官员，这听起来好像在您的情况下相当有争议。由于R25的R值，屋顶甲板的水分风险不会发生太大变化，但是R型R值往往会更高（由于屋顶甲板较低的温度）。但是，如果没有内部水分来源，例如25个汗水的Bikram瑜伽学生，风险很低。
Batts不适合I-to-to-to-to-trafters，因为宽度是为1.5“框架设计的，而不是0.5” i-to-to-to-to-to-team织带的设计。您可能需要用棒刀进行相当多的切割和雕刻，以使其适应不错。
如果不是热轴，则面对箔片的polyiso仍然比聚苯乙烯慢，并且炭化而不是融化成水坑O'flamin'olymer。在本地代码中经常修改点火障碍的要求（通常要宽大处理 - 不确定代码或代码所说）。但是，除非有点火源，否则风险很小。
（编辑长度）再次感谢您的帮助。
在本地，我可以得到rmax Thermasheath-3。https://www.rmax.com/thermasheath-3/
这与陶氏热门相当吗？
Shouldn't the rim joist insulation be permeable enough to allow drying to the inside? (Do I need the ignition barrier there?)
Any feedback on my original exhaust fan questions above (2 and 3)? If code doesn't apply, is this still recommended?
Kevin,
To keep your crawl space dry, the first step is to pay close attention to exterior grading. Make sure that the soil around your building slopes away from the foundation on all four sides.
If you have any reason to believe that the roof water is contributing to crawl space moisture, install gutters at the eaves, along with conductor pipes to convey the roof water far from the foundation.
下一步是密封爬行空间通风孔，并在空气密封和隔热细节上做得很好，以创建条件的爬网空间。这是一篇文章的链接，告诉您该怎么做：Building an Unvented Crawl Space.
代码需要（a）热轴或（b）点火屏障，以保护爬行空间壁上的刚性泡沫。代码解释差异很大。在您的建筑物中，在您的农村地区，您可以选择忽略此要求。也就是说，如果您的家人有任何关注消防安全问题，请找到一些热力器或用1/2英寸的干墙保护泡沫。
代码还要求这种类型的爬网空间具有条件的空气或通风，但是如果我是您，我只会监视爬网空间，然后在安装任何风扇之前先查看其工作原理。在紧缩的是一种便携式除湿机中，您可能需要全部运行几个月才能使事情保持稳定。
祝你好运。