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How do we know that 3 to 4 inches of closed cell is enough? Post New Topic | Post Reply

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Caleb DeFord Posted: Mar 24, 2011 01:43 PM	How do we know that 3 to 4 inches of closed cell is enough? 3 to 4 inches of closed cell foam in an attic is widely proclaimed among the industry as the maximum amount needed for an attic in the typical house. Why? How do we KNOW that's true? I know we have the heat loss equation that shows us we have 90% efficiency at 2 inches of closed cell, and field examples show that 3-4 inches will keep condensation from occurring, but do we have any examples of 3-4 inches of foam performing more efficiently than 15 inches of blown cellulose in an attic?
jimcoler I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs. I've expanded my knowledge into t Posted: Mar 24, 2011 10:12 PM	Obviously, you must not own an IR camera and have an attic to go up into with cellulose in it. If you did, you would see the heat loss areas show up clearly. With 6" of foam consistently sprayed, it should not show much heat loss or much of a difference!
Daniel X Posted: Mar 24, 2011 10:50 PM	Why not spray enough foam to create a vapor barrier and really decent air seal and put a few feet of loose fill on top?
Dean Nash Posted: Mar 25, 2011 08:19 AM	We've been conditioned by Big Fiber & Big Cellulose to accept that more is better so you're question is one they are happy to hear. The danger here is to allow yourself to become fiber-fodder by comparing the products equally. That is what they want us to do IMO. By providing, and therefore condoning the goal of Big Fiber/Big Cellulose, a quantity of insulation solely based on the R-Value,,,(a lil foamdude plagiarism) we effectively address only the conductive value of that product and diminish our products ability to address the other methods of heat transfer. The confusion here is relatively simple: the building code attempts to generalize and with conductive insulations they are able to do so however with Foam, they NEED to address multiple factors that have been supplemental and separate from conductive insulation traditionally. Foam's ability to address 5of6 or all 6 methods of heat transfer demand it and by ignoring those variables, the applicator can potentially cause more harm than good. As mentioned by dl & Cooler, the facts & technical gizmos can and do easily prove that foam outperforms fiber BUT we mustn't generalize or make blanket statements. Our stewardship & market share expansion efforts will not succeed using this approach. So, to answer your question as tactfully as possible- There are countless studies that prove the merits of our respective products however, the Industry has not fully discovered, determined, been completely educated, nor do we have the ability to convey to code enforcement and the public; a uniform insulation standard that allows for climate zone inconsistencies, let alone structure specific inconsistencies. A testament to the value & need of an SPFA or other organization, perhaps. Price the job & let the needs of THAT job determine your application. Joe
maurice richter Posted: Mar 25, 2011 06:27 PM	JAG3 (or anyone willing to jump in) I realize that it would be tiresome to post the entire answer, but could you point to the information you are referencing? In HVAC classes, they tell us there are 3 types of heat tranfer. NOT TRYING TO DISAGREE! Really, I want to learn! If us homeowners could learn even some of what you pro's know, then maybe your job would be easier? It seems a lot of what you pro's are spending time on is educating your customers!
quentin Posted: Mar 25, 2011 06:49 PM	I have actually been trying to find good studies by government testing and equations to show it performs better to beat out the other types. The problem is fibercrap and paper have the money so they get the studies while those in our industry haven't really funded the studies from INDEPENDENT testing groups to be able to convince many. Most people will look at a study and if it is only produced by the people with a vested interest then they have a problem believing it does work so much better. I have tried to get the SPFA to push for this with no luck and it is just one of the reasons I dropped being a memeber of them. When we have to fight the other products and then I keep being hammered by the ABAA requirements that are insane and expensive so that only a few companies can meet them, then why be a member of an organization which really does nothing for us? Until something like this can be taken care of, we are all going to be in the same boat with the regulations and convincing many skeptical clients it is worth the extra investment to use foam instead. We do KNOW it works better for basic reasons like that R 0.5 coffee cup we can show people, freezers in everyone's homes and how well that camp cooler works with them all being foam but it is the public we need to get to understand with some actual help from the manufactures of supplies, materials and equipment needing to get off their rears to help get the studies done instead of just raising prices on us and demanding we sell it to help them make money too.
Posted: Mar 26, 2011 01:23 PM	q: mason offered you the studies: they say what they say,,,foam is foam,,physics is physics,,,an effective air barrier matters... fighting other products???welcome to the world of sales,,as long as theres cheap you will be sellin against other products,,,deal with it,, and if you feel you are being hammered by any organizations specifcations,,, you have tunnel vision,,,consider,,you shouldnt be bidding that scope of work in the first place,,,and no,,i am not an abaa member,,, you beal you want studies showing performance so we can get specification preference,,,well the abaa has and is doing just that...working with the aia to develop a protocol for the air barrier assembly utilizing spf,,and by golly they aint gonna have hillbillys like me slingin it on the walls with my heated hose froth pak super duper refillable wonder rig,,,no,,,they have developed a critera to follow so that the installer can show they have met some "standard" known to the industry,,,so that the install,,and more importantly,,the products manufacture process goes as it should....guarenteeing performance,,,which is what the architect,,owner,,and general contractor was lookin for,,, hey,,,take the courses,, they aint that hard,, pay the dues,,, belong to something,,,lol... and its tax deductable..rofl,,, if ya think about it q,,,they are doing exactly what you want,,getting spf spec'd,,no questions asked,,,cept maybe who puts it in,,,(but have you seen some of the work out there lately..lol)
quentin Posted: Mar 26, 2011 06:06 PM	I know what you are saying dude. I looked at the studies from Mason and have been workign with those. The big trick is that all the studies so far have been by non-independent groups or companies instead of something like Oakridge Labs. Of course selling foam is not hard except when the codes are based on the performance of fiber and other crap. People really gasp if you quote them an R-49 of closed cell on an attic! LOL This is why I am pushing to get it so we have an alternative to the golden R value joke since it does not take real world physics in to account and only conductive resistance. Also there are no real air barrier requirements in the code beyond the joke vapor barrier that craft faced fiberglass can pass. You are right on science being the key and I also will happily join an organization that works for me as well as me working for them. It is a shame though that we have several that compete for those of us in our industry and none of them are willing to look at the others and allow you to be certified by one and it qualifying for the others or just one certification that all agree on. Instead they all want to get their piece of the pie on our money and if we want to get all those little pieces of paper, we will have pay through the nose and it increases our prices that we have to pass to the consumer. So my gripe is really that there are just too many competing groups, requirements and codes that demand our attention but none of them are really any good for us and some are even bad for the consumer too. We have the science, we have the technology and the people want us to build them that better structure for less than the million dollars to rebuild and astronaut! LOL
Posted: Mar 27, 2011 05:56 AM	independant studies is exactly what you want,,, thats what these "houses" do,,,they are recognized for their expertiece in professional independant evaluations,,,much like the icc-es,,lol,,, .. it costs a boat load of money to run/adminestrate these organizations,,, your $1000 a year dont pay the electric bill,,, you cant always get what you want but if you try sometime you just might find you'll get what you need.... mick
quentin Posted: Mar 28, 2011 01:10 AM	Maybe I missed something in the studies so I will check again. Don't mind paying for the groups, just like to see something in return for that money.
Posted: Mar 28, 2011 05:21 AM	more than likely you wont find "what you want to find",,,it is what it is,,and it aint what it aint... and yeah baby,,thats what i want,,,government studies,,,pmpilsh consider: the sips folks offer and deliver increased performance by filling the wall cavities with foam,,,they use even thicker panels for the roof/ceiling panels,,,physics is physics.... if you read thru the perty trade rags with their low or no energy use homes what is the common denominator???they all have thick walls full of foam or some other insulation media and even thicker than normal roof/ceiling assemblies,,usually full of foam... you have to decide at the design phase what you want,,,,a cheap insulation package (cause it can be delivered),,,or a high performance insulation package,,, (q:if you were abaa you would/could see lots in return for your $$,,,lol,,and again,,no,,im not)
Dean Nash Posted: Mar 28, 2011 09:12 AM	Methods of heat transfer: 1) Conduction 2) Convection 3) Radiation 4) Air Infiltration 5) Air intrusion 6) Moisture As an "insulating system", a weakness in any (1) of the above diminishes, or worse relative to moisture, the performance of the other (5). Increasing the respective value of one as is the case with increasing R-value doesn't necessarily mean that the overall performance will be better. An "insulating system" needs to address all (6) methods in order to successfully combat a geographic regions climate zone & IMO one should always allow for those rare but deadly, climatic events. Using the minimum accepted value may not be enough and by that I mean: one cannot just increase R-Value alone & receive a better "insulating system". Hope that helps Joe IME
quentin Posted: Mar 28, 2011 04:24 PM	Thanks guys! Looked in to the ABAA a couple of years back and decided to look again now. Being a small company it is hard to drop a few grand unless there is a good return on it but it seems the costs from them has come down. May have to drop the cash there since they at least open up a bunch of work for us. Maybe the SPFA should look at merging with them or something so there is a tangable benifit for the contractors unlike what I see from the SPFA at the moment.
Caleb DeFord Posted: Mar 28, 2011 05:26 PM	Thanks for the input crew. I'm still wondering though, if we don't have any tests to back up our claim that 3-4 inches is enough in an attic, then what is our claim based on? Who came up with the 3-4 inch rule anyway? On what did that nameless person base his recommendations? foamdude, are you saying that you don't think 3-4 inches of ccfoam in an attic is enough? If not, why? Quintin, could you send me those tests Mason gave you? I would be extremely interested.
Caleb DeFord Posted: Mar 28, 2011 05:36 PM	maurice-r, for more info on the 6 principles of heat transfer that Joe referenced go to:
Posted: Mar 28, 2011 06:03 PM	pends,,,on alot of things,,, broad generalizations get peeps undies in a bunch,,,so,,, what climate zone are you suggesting this application??? and when you say attic,,,just where do you mean,,,flat lid app..or cathedral type app?? what are your "space constraints",,,are you limited in depth influencing your application decision,,,or do you have more depth available to you to obtain additional rvalue in the attic assembly??? are you limiting your appliction due to depth constraints or cost contstraints,,, i have many 3-4" cc apps here in zone 5,,for example in the converted screened porch with the 2x4 truss assembly,,,yep...3.5" on the heel and as quick as we can get her out deeper we do,,but,,there are no ice dams hangin on these rooms,,,none,,(you've got to knock knock knock,,,on wood),, if not why?? i prefer to sell increased performance,,you spend more money,,you see less in your month utility bill,,,simple as that,,, and,,(more importantly if your a foamer) if you draw a line,,,and it is the edge of a cliff,,,i want my builders,,and me,,a giant step back from the edge of that cliff,,,not even a big step will do,,giant step,,,and over the years the giant step has provide great security,,,we have no failures,,,our houses work as designed,,,the customers are happy,,the builders are happy and keep callin,,,im happy and keep workin,,,my homes are happy and keep workin,,, .... so now they pay me for 5,,,i give em ~6,,, or in a 2x6 i charge em for 4 and shoot em to ~5,, they luv me man,,,hold on the phones ringin,,,
SprayFoamSupply.com Posted: Mar 28, 2011 11:11 PM	Have you read Roger Morrison's article, "Determining Insulation Thickness"? Link at left. George
Posted: Mar 29, 2011 08:17 AM	who me?? and does it have big words???
Caleb DeFord Posted: Mar 29, 2011 10:18 AM	Thanks for the article, George. The article makes good sense, but it seems like it contradicts the last page of David South's "R Fairy Tale" example of the potato storage facility where 2" of foam still allowed condensation to form. I don't know, maybe the RH in potato storage buildings was much higher than the example Roger gave about the building with the tropical fish aquariums. I wish Roger would have been able to insulate the roof of that fish place with an inch and a half of foam and demonstrated that it wouldn't condensate. Seems to me that all we can do is make recommendations based on logic, experience and manufacturer recommendations and stand behind our work if it fails. hhmmmm....I think I know why the dude tries to stay away from the edge of the cliff.
angus mcdougald Posted: Mar 29, 2011 06:34 PM	Not to be a bs nerd (building science), but I really think that methods 4-6 of heat transfer are really versions of 1-3......
Caleb DeFord Posted: Mar 29, 2011 06:55 PM	Not really. Read Roger Morrison's article posted at left.
Posted: Mar 29, 2011 07:22 PM	NERD!!!
quentin Posted: Mar 29, 2011 09:38 PM	NERD!!! Now, today we got a gift at my house that is a great example though. Food packed in dry ice can be shipped and most of the ice is stil intact with the outside of the container with the ice directly on it not being cold. So with 1-2 inch thick foam they can ship stuff STANDARD shipping instead of overnight or etc and still not have any worries. We have gotten some items like this in the middle of the hottest summmers too and same results. So in the end this tells us that they obviously know something since they are not using other types of products and if we did the same with most any other product you would see a problem with the thermal transfer. The foam blocks the air, moisture and rest all on its own without any need for other things tossed in to protect it or help it work. When you add in all the things that would be required of other products to perform like this, the costs would likely be higher than for foam.
Posted: Mar 30, 2011 07:51 AM	q: risk justify their costs,,,, now there's that there cliff out there,,, and to your builders that cliff is risk,, you you represent a GIANT step away from that cliff,,, risk=money,,,and all the associated headaches hassles and other badness,,, ,,,part of a team,,,a system approach to building,,,set,,down,,hut,,,
Dean Nash Posted: Mar 30, 2011 07:51 AM	You bring up another good point Quentin- The refrigeration industry has been using foam for what, 40 years or more. Cold storage tanks that require temperatures below -20 degrees(F) are spec'd with 4" of CC topped off with a protective polyurea coating and do a superb job at maintaining that temperature. Discounting the technology learned & the efficiency of modern refrigerator and freezer manufacturers and their use of CC foam seems a little on the futile side IMO. Another news flash that disappeared quickly from the public eye was the BASF sulfuric acid barge that capsized on the Rhine River about two or three months ago. Can't find much news on it these days but from what I've been able to find, it didn't spill a drop and the blurb I saw on one of the news channels stated that it was "reinforced" with CC foam. Seems the last industry to embrace the merits of our product is ours. Sad!
angus mcdougald Posted: Mar 30, 2011 08:56 PM	Maurice is correct with the three. In nj we use aha software that does not correctly model the true insulation value of foam.... many times we have to add 5 inches to hit the numbers... not sure about treat, but if some people want to lobby energy modeling software to fix the software, I am in... If you use other software, do you find this same prob? any names of other software?
quentin Posted: Apr 01, 2011 02:28 AM	Here they demand a rescheck or comcheck which is a DOE product but it also does not model foam properly. It goes strictly on R values and doesn't even ask which material you use to insulate. Luckily most places around here the officials don't demand it but in my county they do. I had to decide to not even bother doing work in my own county since to give them what they want you have to have the wall values, floor values and windows and everything. Now with the super high sloped roofs in style here most people just go with blown in since they can reach that magic number cheap for the attic instead of even foam on the ceiling so I am being required to actually cover the work of myself, the other insulators, the framers, window installers and everyone else. If they change anything then it means my model is off and they want to hold ME responsible. Sorry but I am not going to be held responsible or liable for other contractor's work, much less when they allow EXPOSED fiberglass in plastic bags to pass against code. You are right on the risks dude, too bad some officals try to say I should take the risk of other contractors which is my biggest beef with the locals.
mason Posted: Apr 01, 2011 09:22 PM	Quentin, you should notice that one of the studies showing sprayfoam performing better in attics than fiberglass was conducted at Oakridge labs. Other studies have shown similar results in research conducted by the National Research Council of Canada and at Syracuse University. The key is to get the test procedures accepted by the ICC Evaluation Services so that manufacturers can use the results as a way to get acceptance for their products at R values less than the code tables. I think some more tests at the facilites named above will do the trick. But it will cost some to do it. For example, the attic test cost us around $50k By the way I was instrumental in getting the American Plastics Council to do a series of those tests at ATI back in 2002. The results were not released. All of the foam plastic groups participated. Though the results were not released except to the respective organizations, I know that sprayfoam outperformed the other products by a considerable margin.
Posted: Apr 02, 2011 06:58 AM	double-naught-top-secret-information,,, ,,,you want the truth,,, ,,,you cant handle the truth??? rofl i think
Scott Plantier Posted: Apr 09, 2011 11:05 PM	" The results were not released" Mason-I don't know why the results were kept mum and I guess since nobody else asked why that they already know! Do we need an FOIA request or are the fg people that powerful?