要发泄或不发泄，这就是问题

马修·阿曼|发布能源效率和耐用性上April 18, 2011 10:49am

O.K., I don’t want to be controversial, but in lieu of a recent high priced truss bid, I am thinking of constructing a roof with TJI rafters and am thinking of not venting it. The ceiling will of course be cathedral, the joist rafters will be 16″ tall, and I had planned on using plastic accuvent baffles continuos up the roof to create the venting channel, dense pack cellulose below. I do plan on a vapor barrier, ADA approach, or at least very fastidious air sealing…..Any thoughts, please share.

回答

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答复

道格·梅斯弗斯（Doug McEvers）|4月18日，2011年11:00 pm|＃1

马修，

我将通过将纤维板护套安装到顶部法兰的底部来创建通风口。如果您觉得密集的包装会产生很多压力，而是使用胶合板。我会发泄屋檐和山脊，每个after都有自己的通风孔空间。我已经使用了无数次的系统，结果很棒。塑料通风孔将被爆破的绝缘粉碎。
马修·阿曼|Apr 18, 2011 11:10pm|＃2

I am considering cavity fill, which will supposedly be a little less dense am may not crush accuvent baffles. When I handled the accuvents, I felt like the corrugations could resist 3.5 lbs/ cuft, but I could be wrong. Any experience or thoughts on the "cavity" fill?
安倍·德格兰（Abe Degnan）|Apr 18, 2011 11:21pm|＃3

您也可以使用1.5英寸或2英寸的泡沫代替纤维板或胶合板，因为它也可以抵抗密集的包装并添加到R值中。以前成功做到了。否则，请考虑使用内置通风口通道的层压绝缘/护套，将其放在I型咖啡师的顶部，也许您甚至可以减少I-to-to-to-to-to-to-to-topther深度，或者利用较厚的绝缘材料并获得完整的热休息。
http://www.degnandesignbuilders.com
马修·阿曼|2011年4月19日上午12:59|＃4

感谢您的回答，我还想知道塑料通风口通道在其与蒸气紧密的干墙（夹心纤维素）之间以及它与金属屋顶（三明治胶合板）之间形成双蒸气屏障。我真的应该担心这个吗？
Matthew Nolette - So Maine CZ 6A|2011年4月19日下午2:56|＃5

I think Doug and Abe nailed the vent channel built from the top-chord of the I-joist with foam.

我是唯一一个惊讶的是，I-to-to屋顶被认为是较便宜的替代品？考虑到强制性的结构脊，衣架，添加的柱子和基础，网络加强剂，rafter尾，劳动力，人工和更多人工，我认为桁架会取得前进的成本。我不能肯定地说，不看到设计，也许我们只是在谈论大教堂天花板区，而不是整个屋顶，但我感到惊讶。
马修·阿曼|2011年4月19日下午10:36|＃6

The pertinent rake walls and footings below are definite considerations, but with the I- joists, hangers (webs not required) and needed gluelams, I am still around $4,000 vs. $7,000 for the parallel chord trusses. Also, the 18" parallel chord trusses had much more deflection potential than even the smallest series I-joist @16", so I thought this was important to consider as well. I like the foam idea, but it is definitely cost prohibitive, even tough it is adding insulation. The rafter tails were going to implemented even with the trusses. My other option was to use scissor trusses, but that severely lowered both inside and outside pitches, this due to the fact that minimum allowed slope for blowing in cellulose is 2 in 12 pitch. I hear you though Matt, maybe I am choosing to ignore or am not thinking thoroughly through how much labor this process will end up taking. It is counterintuitive that trusses would be out priced by any cut roof, but it seems so in this case. I think the devil could be lurking in the details of the rake wall construction and the miscellaneous added details you mentioned Matt . I appreciate your Questioning of this, potentially saving my ass.......
Matthew Nolette - So Maine CZ 6A|2011年4月20日上午08:18|＃7

这就是社区的目的；这就是为什么我们发布。很高兴有帮助。
马修·阿曼|Apr 23, 2011 09:04pm|＃8

The devil is apparently lurking in the construction bank loan appraisal process, where green features are assigned no added value. This project is being held up by one person who represents a system that does not comprehend the tangible values of saving energy and conserving resources. Please share, I need some camaraderie right about now....
Keith Gustafson|Apr 25, 2011 07:27am|＃9

您正在使用哪种类型的银行？

Small local banks tend to have more flexibility than the monster banks. They may like having their sign in front of a green project
[编辑]和购买友好评估师的购物并非闻所未闻。我自己做.....
马修·阿曼|2011年4月25日上午10:26|＃10

Keith，客户选择的银行是当地的小型银行，据我了解，新的评估法律，银行无法选择评估师，该过程必须是随机轮换的。有人告诉我，我们不会得到更糟糕的评估师。我希望我们能通过吗？！？！？..............................
Keith Gustafson|2011年4月25日下午3:44|＃11

我认为他们曾经[远了20年]，几年前我遇到了一个不同的问题，并且能够做出不同的评估师。现在，评估师现在非常偏执。但是，我甚至会说，如果您找到了专门从事温室的评估师，或者至少有良好的工作知识，您可能可以将它们列入银行清单（再次，BOA会做的事情，BOA会做的事情]我的银行为我为律师所做的。这可能不再是可能的，但是我认为，如果您发现这样一个人（他们存在吗？）对话是值得的

另一个问题可能是银行打算出售贷款。如果银行打算将贷款保留在国内，则可能会影响他们愿意做的事情。我的银行将某些贷款保留在家中[15年固定和其他问题]，我认为大多数建筑贷款都会保留在国内。

[I looked up the new rules, and mostly it sounds similar to rules in place here in the People's Republic of Mass and it does not look like there would be anything preventing a buyer from selecting an appraiser, only the realtors and loan brokers are verboten]

At the end of the day a 3 BR 2BA house on 1 acre in zip xxxxx is going to be worth whatever the 3 comps the appraiser finds are.

我不认为任何评估师是交易中的“上帝”，但是您可以将您提议的房屋与该地区的其他补充进行比较，并弄清楚将其提升的最佳方法。IE 4 BR的价值超过三吨，也许阁楼成为卧室，或者那室室上淋浴，或者屏幕门廊的价值比甲板或...............
Robert Hronek|Apr 26, 2011 12:54am|＃12

Mathew and Keith

The problem may not be with the appraiser. Many MLS systems provide no information on energy efficiency. The appraisers job is to reflect value placed on real estate by the market. If there is a lack of data the appraiser will be unable to support value added. A lot of good appraisers have left the residential lending field leaving crappy appraisers willing t o work for peanut.

您需要做的是查看是否有任何专门研究能源效率的评估师。与评估研究所等评估组织联系。希望专门的评估师能知道贷方可以贷款。

You may also want to go to appraisersforum.com Post their seeking thier advice.