blown-in cellulose vs. blown-in fiberglass

[robhelms]

"bad science" "unfortunately meaningless" Wow, so from a copy of a copy of a picture off the internet you are going to make blanket statement of that nature? Seems like a rather biased response.

Okay, please then post some hard fact data that either disproves this information, or substantiates your stance. I find it interesting that you are so quick to dispell this data, but all you can use as fact is you think the Cellulose looks like marbles. Actually to me it looks like cellulose. Even with the picture blown up it is not that clear as to be able to tell it is some poor quality material. I have been using cellulose for 30 years, and i am aware that there are lesser and better grades of it. But even the best grade can contain some variation of quality. I can always pickout some small pieces of newspaper that still have print showing on them.

[robhelms]

Jack i never answered your questions. I would most likely go with Cellulose, although fiberglass is a viable solution as well. As far as installing it in a closed wall, fiberglass when blown at the proper speed, and air pressure and in the right machine can be processed to where it is very small and will fill nicely. However i still like the whole package for cellulose in blind of dense pack blow. I prefer the tube method, however many feel you can not pack without it, i do not beleive that either. Sure not with a small to mid sized electric machine. But with a larger PTO machine like a Unisul, or Meyers you have far more adjustments and settings to use to make it work. I have dense packed with a directional nozzle and even at time with just a hose and years later seen the drywall taken off and the material was a virtual BATT and just stay in place with out the drywall on one side.

Still a tube style blow is the "A" way to go!

[Energy Man]

[krendlguy]

Hey - great discussion but I think this is getting too technical for a lot of insulators. Seems like most everyone agrees that cellulose is the obvious choice for existing homes with empty walls where insulation is to be blown. When the rubber hits the road I want a product that performs great in a variety of circumstances, is easily installed and is cost effective.

[robhelms]

Also at other post with video:

We buy about two to three full truckloads of Greenfiber per month, we buy the borate stabilized and find it a very consistant and solid product. I have used other brands in the past and see very little difference in the products. The greenfiber bags i see out here at Home Depot are smaller and not the borate stabilized version I have not tried. Greenfiber is a Louisiana Pacific company and is the dominate supplier in the country. They make over 60% of all cellulose made in the US. That is the reason i suspect JM used their product in the testing. I am currently running down who did the testing and will post those results as soon as i have them.

[robhelms]

I did a little research and spoke to the gentleman who's name is on the testing. Jim Fitzgerald is the director of Building Diagnostics with The Conservation Services Group in Minneapolis MN. He has over 30 years experience in the field in implementing quality insulation and air leakage management practices. Jim invented Dense packing with his company many years ago. He sits on several boards of companies that study and develop the science of air movement and management in buildings. He teaches the use of infrared cameras and blower door systems, and well as teaches classes on dense pack. I tracked him down and had a very detailed conversation on the phone about his testing of Spider vs Cellulose.

He did not do JMs testing but he was asked to verify it before it went to the public. He expressed as energyman did the product that was used as well as the 3.0 density of the test. Both of these he said were a problem. What he did tell me is that he has done his analysis of the product and it holds up nicely to the test. His words to me is spider is the real deal. at a 2.2 lbs density it does match the best installation cellulose can give and does not fall short at all. His view on this is that while he remains a fan of cellulose the spider has compellling features. It take less air to blow, fills just as good, is less dusty, and really performs.

He is continuing to do detailed testing and is very positive on this product as a very viable solution to the densepack family.

Here are some of the references forMr. Fitzgerald

http://www.csgrp.com/press/press_releas ... gerald.pdf

http://www.affordablecomfort.org/images ... andout.pdf

http://oikos.com/esb/46/basement.html


In closing my whole purpose for this discussion is not to bash cellulose, or to promote fiberglass. But to be honest, as our industry is filled with personal propaganda, i have been guilty of it myself. We should be honest and forthright about the products available. Give the customer factual information. Be responsible and accountable. This is how we grow in the industry from being an afterthought trade to a viable and important part of the building science. For decades we have been that trade the is sandwiched between framing and drywall. What we do is important, and it should be treated that way. I hope nothing i have said, or the way it was presented offends anyone. I look forward to futher interesting conversation with you dedicated professionals. Rob