开放细胞与纤维素
罗伯特·赫罗克（Robert Hronek）|Posted in一般的问题on
In retrofitting walls how does open cell and dense pack compare for air tightness?
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That's a pretty narrow basis for comparison.
Spray foam, if installed properly - the right mix, the right rate, the right substrate temperature - will always be somewhat more air-tight than any fibrous insulation. But dense-pack cellulose does a better job at reducing air movement than any other fibrous insulation because of its exceptionally high density. It has been third-party certified as a fire stop because of this and its fire-resistant quality.
For instance J CHESNUT (12/23/2010) reported here that "My CFM @ 50 Pasc was reduced from 2,925 to 1,625. I did some minor air sealing around the house but this is mostly due to dense packing the balloon framed walls with cellulose."
But cellulose offers so many additional advantages with none of the disadvantages of petrochemical foam, such as off-gassing, possible shrinkage or separation from shrinking framing, and fire and toxic smoke contribution.
Cellulose is highly fire-resistant, insect & rodent resistant, mold resistant, non-toxic to humans and pets, excellent sound dampener, 100% recycled, very low ecological footprint, recyclable and compostable, and has a higher R per inch than open cell.
Additionally, it's hygroscopic qualities allows it to buffer indoor relative humidity, absorb and release up to 30 times its weight in moisture, draws moisture away from wood framing and thus protecting it, and allows the house to breathe.
It's also less expensive, no one has to vacate the house or wear a hazmat suit during installation, and it makes renovations or mechanical system repairs much easier.
罗伯特，
The best data on this issue were collected by researcher Bruce Harley. I reported on his findings in the April 2005 issue ofEnergy Design Update.
Harley reviewed blower door test results from 906 recently build New England homes, and sorted the data by insulation type. The data clearly showed that homes insulated with cellulose (average air leakage, 0.31 ACHnat) were tighter than homes insulated with fiberglass batts (average air leakage, 0.38 ACHnat), and homes insulated with spray foam (0.26 ACHnat) were tighter than homes insulated with cellulose.
这是本文的一些摘录：
“最近，马萨诸塞州韦斯特伯勒的保护服务集团住宅能源服务技术总监布鲁斯·哈雷（Bruce Harley）能够在许多建筑物中研究气密性和绝缘类型之间的相关性。单户家庭和多户住宅）于2004年在马萨诸塞州和罗德岛州完成。所有房屋在完成后都经过了打击器门的测试。
"...Harley found that houses with walls insulated with spray polyurethane foam were significantly tighter than those houses with walls insulated with cellulose, and that houses with walls insulated with cellulose were significantly tighter than those insulated with fiberglass...
"Although the data clearly show a consistent correlation between insulation type and airtightness, the reasons for the correlation are unknown. It is possible that builders who choose cellulose or spray foam insulation — both of which have a reputation for resisting air flow — may be more meticulous in performing air sealing tasks than builders who choose fiberglass batts. Perhaps builders’ attention to detail in certain areas unrelated to insulation performance — for example, careful sealing between wall bottom plates and subfloors — partially explains the measured differences in airtightness. If this theory is true, the extra dedication to air sealing may be motivated by the builders’ desire to justify the added cost of spray foam or cellulose over fiberglass batts.
"However, the principle of Occam’s Razor favors a simpler explanation: that the measured differences in airtightness are due to differences in the material characteristics of the different insulations."
马丁
Thanks for the information, I assume I can find a link on that article. Do you know if there are any shrinkage issues with open cell foam. Regarding the off-gassing, I've seen a few complaints from homeowners who used open cell foam in existing homes but haven't seen much evidence in new homes. Do you have any information on this?
Allan
Allan,
我不认为EDU文章在网络上可用 - EDU的大多数问题不是 - 但我进行了搜索，您很幸运。它在这里发布：
http://www.aspenpublishers.com/pdf/ss07413629.pdf
我提到的文章从第10页开始。
All of the cases of spray-foam shrinkage that I have heard about arose because of problems with the chemicals being mixed, bad mixing ratios, or installation in cold conditions.
JLC发表了梅森·诺尔斯（Mason Knowles）关于喷雾泡沫问题的精彩文章，并发布在网络上。一探究竟：Troubleshooting Spray-Foam Insulation。
正确的是，大多数广为公开的喷雾泡沫示例超出了燃烧的投诉，来自被占领的现有房屋喷洒的泡沫。但是，这个问题仍在调查中，我认为现在就问题的程度得出坚定的结论还为时过早。
Allan,
Here is a link to the April 2005 issue of Energy Design Update containing Bruce Harley's article titled "Fiberglass-Insulated Homes Are the Leakiest" on pages 10-11.
http://www.aspenpublishers.com/pdf/ss07413629.pdf
Don
感谢马丁（和唐）。我今天要去奥兰多的NAHB表演，并计划向ICYNENE人们问一下其中一些问题。我知道，制造商将把一切都旋转起来，但我喜欢听到双方的声音。我将随身携带iPad，并计划向他们展示有关其产品（尤其是Robert's）的一些GBA论坛文章。
Allan
For "air tightness", ocSPF wins every time ... IF "perfectly" installed by a highly skilled installer, etc., etc. etc.
对于已知的致癌物，生物蓄积的诱变剂，多化学敏感性启动器/加重器，致命的氰化物消防 - 烟雾发育等等等等。
Not a contest I'm interested in "winning" in the spaces in which we spend the greatest majority of our lives just to save 0.05 ACHnat.
Andy,
很好。
马丁,
I think it's a bit disingenuous and misleading to claim a significant difference between 0.26 and 0.31 ACHnat. That's probably within the margin of error, and it compares averages which can be skewed by the extreme ends of the curves rather than medians. It also fails to compare houses that are entirely insulated with one insulation type, separating wall insulation from ceiling insulation. So it's not clear from the article how useful or accurate the conclusions are.
我最后的测试在0.10 ACHnat密实充填ADA的房子(0.15 with the air inlets open), and that's a significant reduction in air flow from any of the Harley average numbers.
I stand by my statement that spray foam will be somewhat more air tight than dense-pack.
罗伯特，
我介绍了我知道的最佳数据。
The data are in fact significant -- not only because of the differences in air leakage rates shown, but because of the consistency of the correlation. Bruce tried looking at various subsets of the measured houses and each subset showed the same consistent correlation.
So the results are significant from a statistical standpoint. The results demonstrate a correlation.
That said, you can, of course, build an extremely tight house that is insulated with cellulose.
Freudian slip?
Paraphrased from Wikipedia:
在统计数据中，如果不可能偶然发生这种情况，则结果称为统计学意义。如统计中所使用的那样，显着并不意味着重要或有意义，而是在日常演讲中所做的。结果可能具有统计学意义，但差异可能足够小，以至于完全不重要。许多研究人员敦促应始终伴随着效应大小的统计数据，这些统计量近似于大小，因此差异的实际重要性。
For lack of a nail, the shoe was lost. For lack of an "a," my meaning was changed.
Several months ago, I am not sure I have the name right, Mr.Susz posted a comment about his experiences with blower doors tests. He said he would post results of his tests but I never saw a follow up. His original comment led me to believe the cellulose was very close to achiving the same results.
我感兴趣的是改造现有的墙壁。改造提出的挑战与在敞开的墙壁上工作不同。安装泡沫虽然管与喷涂不同。因此，我希望Apple到Apple Reuslts。
罗伯特，
If you are planning to insulate existing walls, use cellulose.
罗伯特，
钻孔和填充安装剂的安装程序PAC纤维素的安装者会感觉到材料在管子上的压力所包装的感觉如何。
I wonder how a foam installer gauges how good of a job they are doing in progress? As you are likely aware you can't tell how well a job they did unless it is inspected afterward with a blower door/ infrared cam inspection.
Its a bit of a hit and miss operation. Not only is cellulose non-toxic with far less overall environmental impact it is probably more forgiving if the installers need to come back and fill missed spots if found.
Robert H,
If you're thinking about installing foam through a tube, then you're talking tripolymer or air-krete.
We are working on getting started in energy retrofits. Our idea is to install cellulose and not foam.
In talking with a local foam installer at a home show he talked about installing foam with a fill tube. I also ran across a home had retrofit wall foam, found it when I had a return air grill off.
the guy at the home show described it as open cell. If this is not open cell then how does it compare?
我知道该线程的最后一篇文章是5年前，但是由于我的问题与该主题有关，因此我不想启动新的帖子。
我最近得到了隔热报价，冰河开放式泡沫将比密集的纤维素（绿色纤维品牌）便宜。差异也不是无关紧要的，因为与冰河相比，差额要少$ 1,925。这让我感到惊讶。
I am still reluctant to go with the Icynene because of the concerns with potential voids in my 10" thick walls and potential smell. But with the price difference being that great - it sure it tempting.
Here were the final numbers
2400平方英尺10英寸厚的墙壁
Icynene = $3,975
Dense packed cellulose with netting = $5900
For my basement walls - I'm going with Icynene closed cell spray foam as it doesn't look like there is a better alternative.
吉米，
It looks like you forgot to include your question.
It's common to find open cell coming in cheaper than dense-packing in netting.
2400 square feet x 10" depth is 24,000 board-feet (2000 cubic feet). A price of 24,000 board-feet of open cell foam for $4000 comes under 17 cents per board foot, which is literally HALF what I've become accustomed to seeing. Could it be a misquote? It would have to be installed in two lifts, with a cooling off period long enough to allow the curing heat of the first pass to dissipate fully.
2000立方英尺的3.5磅纤维素为7000磅的材料。即使在批发时，它的材料成本也将超过2个，并且安装人工也比开放式泡沫高。那个密集的填充纤维素也具有可测量的热质量益处。
Icynene's water blown 2lb foam (MD-R-200 or MD-R-210) are greener alternatives to their MD-C-200 closed cell foam, which is blown with HFC245fa.
后被固体推理和数据说服and the proponents of dense pack (such as Dana) , I sought out to find a qualified installer of the product for my house. I did find him and we are using that product in my 2x6walls and attic. I am using some open cell in places where it behooves me and that would be in the corners, above the mud sill and above the upper plate on top of the accuvents, and in the joist bays between the first and second floors. In every stud bay, and between all 2x members like plates and jacks, we are installing elastomeric caulking to increase air tightness. I imagine the tightness will be magnificent with the dense pack and the air sealing measures. I don't think you can just blow in cellulose and be happy with the results if you did not focus some effort and time into air sealing methods. I think there is a place for some open cell foam in a building these days, but doing the entire building is overkill in my opinion.