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Rob Granger Posted: Sep 16, 2007 12:22 AM	Crawl spaces I have two upcomming jobs to apply foam to the ceiling in crawl spaces where the floors are dirt and therefore dampness is prevalent. Should I run a propane heater to dry out the wood some and heat it up. For how long? Any other word of advice?
SprayFoamSupply.com Posted: Sep 16, 2007 07:05 AM	We have sprayed a number of crawl spaces and even though there is alot of moisture present it hasn't been a problem. As your foam supplier what the maximum allowable moisture content of the wood is and check it with a moisture meter, usually 18%. Crawl spaces are no fun and certainly no fun if it is 100+ degrees, so don't run the heater unless you have to. I hope that you are using closed cell foam only as you mention moisture! I have an interesting crawl coming up where the contractor wants us to spray the walls of the crawl and the dirt floor to create a conditioned space and eliminate the moisture. I don't see a problem with this and am looking forward to trying it. Anyone done this already? George
Posted: Sep 17, 2007 07:06 AM	george,,sprayed bunches of crawls the way you described,,they work fine... have a good week bro
mason Posted: Sep 17, 2007 09:52 AM	Yes, closed cell sprayfoam has been used for decades in crawl spaces. I have sprayed quite a few of them myself including my mom's house in Houston back in 1972. It is working fine today. Measure the moisture content of the wood as suggested 18% or less is the standard industry recommendation (similar to painting). As for making a conditioned space, if you are putting in registers to the interior of the house or ducts from the crawl space, you would require a thermal barrier over the foam. If there are pipes, electric lines or other utilities, an ignition barrier is required.
SprayFoamSupply.com Posted: Sep 17, 2007 11:01 PM	Thanks Dude! I am looking forward to trying this. It should be a piece of cake after today. Sprayed a crawl that we could barely fit in. The previous owner had the bright idea of blowing cellulose against the exterior walls. One guy had to go ahead with a small rake and pull it away while the second guy followed spraying. Should have been on that show, dirty jobs as it was by far the worst one yet. My sprayer crawled through a bees nest which was quite amuzing, for me at least! Geo Geo
Rob Granger Posted: Sep 18, 2007 12:26 PM	Mason, I just want to make sure I understand you correctly. If I spray a crawl excluding the dirt floor and it has no vents to the first floor I do need an ignition barrier on the foam?
mason Posted: Sep 18, 2007 12:38 PM	Check with your building official ahead of time. Some allow the use of bare foam if there are no pipes, conduit, vents, duct work, etc. The codes state that an ignition barrier is required for attics and crawl spaces where access is only for service of utilities. But, it doesn't mention what is required if there is no service of utilities. It is up to the individual code official to interpret this.
Rob Granger Posted: Sep 20, 2007 11:39 PM	Sprayfoam1, I thought CC was a vapor barrier so why do I need to put another one on top of CC. For those of us that are new what product/system are your talking about relating to a vapor barrier over top of CC foam in a crawl. I am spraying the underside of a sunroom tomorrow where it sits 4 feet off the ground with the bottom open to the air/weather. Do you recommend a vapor barrier.
mason Posted: Sep 21, 2007 10:31 AM	Sprayfoam1, I have to differ with you on this one. I lived in hot humid climates for many years from Houston to South Padre Island, Tex and have not observed any deterioration of the wood in these environments. For example,my mom's house has had closed cell foam installed to the underside of a tongue and groove wood deck in a crawl space application for more than 30 years with no deterioration.
Posted: Sep 22, 2007 06:16 AM	DID SOMEONE DELETE A POST HERE OR JUST WHAT ARE YES AND MASON REPLYING TO HERE? DOES THIS FORUM "FILTER" ITS POSTS? WTF? 'dude enquireing minds need to know..
mason Posted: Sep 22, 2007 09:25 AM	Foamdude, I appreciate the comments and assistance of my readers to assist on answering questions, but when the comments confuse or are wrong I reserve the right to delete those comments. Yes, I will delete a post from time to time if it contains incorrect information that confuses the issue or doesn't conform to the forum's guidelines. The deleted post provided contradictory and incorrect information on vapor barrier requirements for crawl spaces. My response was aimed at the person who wrote the post. In this case the post said that a vapor barrier was required when using closed cell SPF in humid crawl spaces. This is not correct and was confusing the person who originally asked the question. Both historical and research evidence demonstrates that a closed cell SPF will slow down the moisture vapor transfer rate even in a humid environment to the extent that condensation doesn't occur in the wood. If there were a constant vapor drive in one direction, another vapor barrier would be required. For example, a swimming pool or a cold storage project. But in a crawl space, the vapor drive will go both directions at various times of the day and season allowing any water vapor that has driven into the foam and wood to come out again without condensing. Hope this helps.
Rob Granger Posted: Sep 22, 2007 12:06 PM	Mason, Thanks for the clarification. You raised another question for me. I got a call from a customer today who wants a cold storage unit sprayed and my research has brought up the issue that an exterior vapor barrier is required. What type of barrier can I use to bring about the results I need. A professional job withno call back....
Posted: Sep 22, 2007 07:34 PM	mason... thanx for the explanation.. i personally do not like the forums that censor or filter or keylog or otherwise "alter" the public record.. i consider this forum a means to provoke and provide dialoge...and at times untruths,,,,misinformation,,,and at times obvious tripe are presented to the world for consideration... the beauty of the forum is the ability for the topic to be discussed,,,often with these misconceptions addressed with eloquence,,and at times with the direct venom they deserve....that is the beauty of the open forums... and if we change someones wrong opinion/impression/belief we have done exactly what the forum should be doing,,educating and informing.. thanx for your public reply... i value your opinions i thank you for your continued contribution to our trade.. 'dude ...saturday,,in the park...
mason Posted: Sep 24, 2007 10:29 AM	Foamdude, I understand your perspective but this forum is not open and as the title indicates "Ask Mason Knowles", I attempt to answer questions about sprayfoam and the industry. While I appreciate input from the readers, it is not intended to be a free exchange of ideas. There are other forums at SprayFoamMagazine.com that accomplish that purpose. I have a very unique and varied background in the sprayfoam industry and have been answering these type of questions for the SPFA for many years. If I don't know something, I will say it, the information I provide is documented from either personal experience, research or from others whose opinion I have come to trust. Think of this as the columns you read in the newspaper about finance, real estate or home improvements. Those are much more heavily edited than this column. For your information, I have deleted two posts out of 83 topics and more than 800 posts and have not edited any posts other than my own (for clarification) since starting the forum. I also leftthe original posts up for a couple of days with my specific reply before deleting it so that the readers would know what was happening.
mason Posted: Sep 24, 2007 10:36 AM	There are many types of spray-on vapor retarders that will do the job. The type used depends on what the performance requirements of the coating are. For example, if it is exposed to the outside, you would require an elastomeric UV resistant coating such as a low perm rated polyurethane or polyurea coating. If it is an inside application, a low cost asphalt mastic can be installed to the substrate, then spray the foam and cover it with a thermal barrier. Contact your foam supplier for their specific recommendations.
Posted: Sep 25, 2007 08:08 PM	Mason, If We are talking a pier house scenario,then No no vapor barrier needed. If this is a closed unvented crawlspace. Then you 100% better put a sealed vapor barrier on the floor to prevent vapor drive from the floor. I spray apply foam in Northeast PA and have been doing so since 75'.If you would like to see such an example of rotted joists or subfloor that has been sprayed in the past I can show you such proof.This info that I provided was not something that I read but rather something that I have seen. Maybe my climate is different. here we have high water tables,with constant moisture drive from the ground.
mason Posted: Sep 26, 2007 10:36 AM	Sprayfoam1, If there is a constant vapor drive in one direction,a vapor retarder is required over the foam but if the vapor drive goes in both directions, you would not require a vapor retarder. You mentioned a very important factor, unvented closed crawlspace with high water tables. You are correct that the crawls spaces I referenced were not sealed but had high water tables with constant ground moisture. I would agree with a vapor retarder on the floor or over the floor if the crawl space is sealed. Thank you for providing that exception and clarifying your original comment.
Rob Granger Posted: Oct 12, 2007 02:29 PM	Mason, Does the code discriminate?? In other words does a garage attic space require an ignition barrier??????
mason Posted: Oct 13, 2007 09:36 AM	It would depend, is the attic space accesible for service of utitlities? Then an ignition barrier would be required, but if there is no access, an ignition barrier would not be required.
Rob Granger Posted: Oct 13, 2007 09:58 AM	Mason, Most of the attics in my area are just for storage whether it be a house or a garage.. Does that change the barrier mandate for either??
mason Posted: Oct 13, 2007 03:59 PM	Yes, No, they still consider those attics to be for service of utilities (such as electrical and cable wires, pot lights, etc). Storage would also classify it for an ignition barrier. The main question to ask> Does it have a access and do folks go up there from time to time?
Gary Galloway Posted: Oct 21, 2007 05:02 PM	I see a lot of debate about ingnition barriers. It had been my understanding that an ingition barrier was only required between the foam and the living space. For example 1/2 inch sheetrock so this tread leaves me with more questions than answers. I know the foam jobs I have seen in my area do not have an ingition barrier in the attic and the central air/furance is in the attic as well as hot water heaters in some cases. Would a heavy alumium foil covering the foam be considered an exceptable ingition barrier ??? Also why would it be nessasary to have such a barrier with class 1 fire rated foam ??? Please try and clarify these issues a little. I am getting ready to go into the foam business and want to be certain I understand the requirements and the liabilities beforehand.
mason Posted: Oct 21, 2007 06:34 PM	The flame spread rating does not give a good indication of how a foam plastic (such as sprayfoam) will behave in a real fire situation. So, in order not to use an ignition barrier or thermal barrier as described in the codes, corner wall fire tests are performed to demonstrate how the foam will react. So, in attics, if a code accepted ignition barrier is not used, the contractor and supplier have a legal liability.
Gary Galloway Posted: Oct 22, 2007 09:17 PM	Thanks for the response. What this means is that my competitor has a very big problem and so do the local inspectors that let the foam be installed without an ignition barrier. Hopfully that will translate into more work for me !!!
mason Posted: Oct 23, 2007 07:53 AM	This was such a large problem involving foam fires in the 70s that the FTC issued a consent decree that all foam plastics were required to follow stating: Foam plastics could not be labeled or advertised as self extinguishing or fire retardent In 2001 Keller and Heckman reviewed the Consent Decree for relevancy in today's polyurethane foam market. The following is a copy of their report to the Alliance for the Polyurethane Industry. "date June 13, 2001 re 1974 FTC Combustibility Consent Decree In response to a member company's concerns regarding recent proposed code changes, API asked Richard Mann, of Keller and Heckman, to provide some guidance on the 1974 FTC Combustibility Consent Decree now that it has "sunset." Specifically, the member company raised concerns about efforts to minimize code requirements for thermal barriers used with polyurethane building materials. Although this Consent Order terminated in 1995, when the FTC adopted a rule automatically "sunsetting" such orders after twenty years, certain aspects of the Order continue to be important industry references as (1) a benchmark of the government's likely position with regard to claims that had been prohibited and (2) a likely indicator of allegedly minimum appropriate behavior for purposes of determining potential product liability. The attached document, authored by Richard Mann, discusses the "legacy" of the Combustibility Consent Order. We feel this summary will be a useful reminder to the industry, and of particular value to individuals who may not have experienced the Consent " " 1974 FTC COMBUSTIBILITY CONSENT ORDER: GONE BUT NOT FORGOTTEN In November of 1974, the Federal Trade Commission and the Society of the Plastics Industry, as well as several individual chemicals and plastics companies, entered into a Consent Agreement and Order that tightly circumscribed certain marketing and sales practices relating to the combustibility of cellular plastics products. This Agreement and its underlying Order terminated in 1995 when the FTC adopted a rule automatically "sunsetting" such orders after 20 years. However, certain aspects of the Order continue to be important industry references as (1) a benchmark of the government's likely position with regard to claims that had been prohibited and (2) a likely indicator of allegedly minimum appropriate behavior for purposes of determining potential product liability. THE FTC PROCEEDING The FTC initiated an investigation in 1972 in the wake of several fires involving cellular plastics products. At the time, there were allegations that marketers of these products were misusing the results of small-scale tests in promotional material, thereby exaggerating or misrepresenting the performance of cellular plastics in an actual fire. In particular, the FTC was concerned about the use of terms such as "non-burning," "non-combustible," and "self-extinguishing" in connection with these products, as well as the use of numerical flame spread ratings based on small-scale tests. The FTC alleged that these tests were not reliable or accurate for determining, evaluating, predicting, or describing the burning characteristics of plastics products under actual fire conditions. THE CONSENT ORDER The Consent Agreement ended a two-year investigation with no admission of wrongdoing on the part of SPI or the other respondents. However, as part of the Agreement, the parties agreed to be bound by an Order that required all respondents to -- • Cease and desist from using, publishing, or disseminating (or encouraging others to use, publish, or disseminate) descriptive terms such as "non-burning," "self-extinguishing," or "non-combustible" in connection with cellular foam plastics products unless they performed as described under actual fire conditions; • Refrain from referencing numerical flame spread ratings in connection with cellular foam plastics products based on small-scale flammability tests without a detailed disclaimer noting that the ratings are not predictive of the hazards presented by these products under actual fire conditions; • Implement a notice and reporting program on the terms and conditions of , and compliance with, the Order; • Establish and fund a research program on the safe and effective use of cellular foam plastics products. THE TERMINATION OF THE ORDER In August of 1995, the FTC adopted a rule whereby all existing and future administrative cease and desist orders automatically terminated after 20 years, assuming that the Commission had not gone to court to initiate an enforcement proceeding under the order while it had been in effect. The Combustibility Consent Order officially terminated at that point. However, for several reasons, it remains an important reference and guide for the cellular foam plastics industry in matters relating to the promotion and marketing of the fire performance of building and furniture materials. First, there is no reason to believe that the current FTC's position would be any different with respect to potentially misleading uses of small-scale tests as predictors of fire performance, as well as use of potentially misleading fire-safety terminology in connection with cellular foam plastics materials. The fact that the FTC cannot immediately march into court under the Consent Order does not mean that the agency cannot initiate an investigation and subsequent enforcement action to respond to conduct that it likely would deem to be in violation of the FTC Act. Second, the Consent Order is a matter of public record and serves as a continuing indication of what the government likely would consider unacceptable in terms of promotion of fire performance of cellular foam plastics materials. What is more, while it was in effect, the requirements of the Consent Order were repeatedly communicated throughout the plastics industry. It is likely that a products liability plaintiff would assert that the relevant restrictions on promotion of fire performance of cellular foam plastics materials are a minimum industry "standard" or practice for purposes of determining liability. Accordingly, while no longer formally in effect, the Combustibility Consent Order remains an important document that members of the cellular plastics industry would be wise to review and understand when issues relating to promotion of fire performance arise.: Hope this helps put the thermal barrier/ignition barrier issue into perspective.
Charles Whittle Posted: May 29, 2008 03:17 PM	I have a vented crawl space under a residence with a 2x6 tongue and grove floor. I get some movement in the floor that is causing problem with the filler between the boards. On occation the ground gets wet under the house and may take a month to dry. Shoud I use a open cell or closed cell foam? and why? Also is there anything else that I need to do before or after I spray the foam. The house is in the Gulf Coast area just north of Houston.
mason Posted: May 30, 2008 02:52 PM