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andy buff Posted: Jan 15, 2008 09:12 PM	box sills Mason,box sills when foamed do they need to be covered?spraying 3' closed cell.......thanks skinny
mason Posted: Jan 16, 2008 08:01 AM	The building codes specifically exempt Class I closed cell SPF at density of 2 pcf in sill plates and headers applications. IRC Section 314.4.11 (2006); Foam plastic shall be permitted to be spray applied to a sill plate and header without the thermal barrier specified in Section 314.4 subject to all of the following: 1. The maximum thickness shall be 3.25 inch 2. The density of the foam plastic shall be in the range of 1.5 to 2.0 pcf. 3. The foam plastic shall have a flame spread index of 25 or less and a smoke developed index of 250 or less when tested in accordance with ASTM E 84.
Posted: May 20, 2009 09:54 PM	but what about open cell foams? so are all these open cell applications in box sills and band joists not icc approved? and subsequently they all need to be covered with a thermal barrier??? and a smoke of less than 250 in a closed cell,,there are a couple,,but wtf????
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: May 20, 2009 10:40 PM	I think Mason meant to write smoke development of <450. To clarify this further the IRC 2009 changed the code reference numbers (316) and goes further with this and states in 316.5.11 section 2. The density of the foam plastic shall be in the range of 0.5 to 2.0 pounds per cubic foot. Section 3. states flame spread <25 and Smoke development < 450 according to ASTM E84 The real kicker of this issue is if there is a material which does not have to be called a plastic foam, they can be left exposed to the living spaces under IRC 2009 Section 302.9 with a Flame Spread of <200 and Smoke Development <450 according to ASTM E84 alone. Alternate testing referenced is UL 723 and NFPA 286. If this product is classified as an insulation, then it falls under R302.10 which states a FS<25; SD<450 according to ASTE84 or UL723. Now we go one step further and Section 302-11 Fire Blocking -R302.11.1.1 through R302.11.1.3 references Batts, Blankets of mineral or glass fiber, unfaced fiberglass and "Loose-fill insulation material". The requirement of these is listed in R302.11 Firestopping where is says "cut off all concealed draft openings (both vertical and horizontal) and to form an effective fie barrier between stories and between a top story and the roof space." There are no flame spread or smoke development guidelines specified or referenced. Section R302.12 Draftstopping also makes no reference to FS or SD. But when an architect or engineer proposes using foam in these applications, we get referred back to the insulation or foam plastic sections. SO how does fiberglass or mineral fiber cut off all concealed draft openings when it just filters air? Another area where foam gets the shaft and is over scrutinized compared to Filter glass and mineral fiber materials. I guess we don't have enough money yet to pay for the codes to be written in our favor. Jim Coler www.coler.com
Posted: May 21, 2009 06:31 AM	our officials use the 2006 book,,so open cell cant be used according to the book??? so if i use 3.8R/inch for an open cell foam and we gots 3.25 inches allowed,,, thats r12.35 in the box sill,,, energy star??not even close,,, wtf??? so open cell foam cant fill the box sill and be left exposed as long as it doesnt extend beyond the cavity into the rooms space???? lets see,,i got about 7" of space and we can only apply 3.25" of foam...brilliant!!! my recomendation to my builders,,,stuff em with an r19 filterglass batt,,it aint worth the extra money for an inadequate foam application,,,why bother,,, maybe while were trimming back the boxsills,,and can we do it cheap???,,,we could be building our drywall boxes for the can lights in the attic... round here we got drywallers slingin foam,,,lawncare peeps and cement dudes too!!!maybe that is the wave of the future,,,cover it before anyone sees it...out of sight out of friggin mind,,, this is assinine.... does any open cell foam suppliers have approval for exposed foam in box sills at a depth of greater than 3.25"???? reducing our dependence on oil,,yeah right,,, reducing our carbon foot print,,yeah right,,, leeds = energy performance,,,yeah right,,, heers = energy performance,,,yeah right,,,
mason Posted: May 21, 2009 07:21 AM	Foamdude, At the 2008 hearings (to write the 2009 ICC codes), a code change was proposed to allow open cell class 1 foam exposed in sill plate applications. I supported the code change but it did not pass. In a sill plate if the basement is part of a crawl space and not used for storage you can use an ignition barrier if not you would have to use a thermal barrier over the foam to be code compliant. Foam used in fire blocking has to be tested as part of the assembly to determine if it performs equal to code designated fire blocking materials. Yes, Jim that was an editorial mistake, Class 1 is 25 flame spread or less and 450 smoke developed or less,(typing too fast)
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: May 21, 2009 08:12 AM	Eve though most areas have not adopted the 2009 IRC, in many cases you can get your code official to sign off on the intended approval of the 1/2lb as it is in the IRC 2009 future code. This sounds like another case of ambiguous codes and oversight where the intent wasn't stated, but a product density was. When questioned, the ICC gave a response that 1/2lb foam was technically less fuel load because it was a lower density and therefore was acceptable to be left exposed in rim joists as long as it is FS<25 and SD<450 per ASTM E84. They stated the test was done on 2lb because it was considered more severe and the approval was intended for 0.5-2.0lb foams. It sounds like it's again who you ask at the ICC and whether their having a good day or bad day and whether you're their friend or foe. Jim Coler www.coler.com
mason Posted: May 21, 2009 01:15 PM	Jim, thanks for the update. I was curious as to why the code change was not accepted in the first round of hearings. However, according to my records the proposal (RB 79 allowing low density SPF in sill plates without an ignition or thermal barrier was approved. So it will be in the 2009 IRC code. From my understanding the tests conducted were identical to the ones used to determine the acceptability of closed cell Class 1 foam sill plates. Still as always get approval from your local code official as they may interpret the codes differently particularly if the 2006 code has a section that is specifically addressing one material and not another.
Posted: May 21, 2009 02:50 PM	to ask again,, will this approval still maintain the 3.25 depth max?????,,, seems this is a closed cell number allowing adequate r value at said depth,,, it is not adequate rvalue at said depth for open cell foams...it does not meet our local energy audit requirements for this area..... if i have a box sill that has about 7" of depth to the face of the box,,the wall face plane,,,why the heck cant it be filled with open cell foam????? uh,,it has less fs and less smoke than closed cell foams,,,, should i let the local code officials know that the newbees who "only do open cell" foam should not be allowed to shoot box sills as the required r value cant be met?????
mason Posted: May 21, 2009 07:35 PM	This what was submitted and approved; "R314.5.11 Sill plates and headers. Foam plastic shall be permitted to be spray applied to a sill plate and header without the thermal barrier specified in section R314.4 subject to all of the following: 1. The maximum thickness of the foam plastic shall be 3 1/4 inches 2. The density of the foam plastic shall be in the range of 0.5 to 2.0 pounds per cubic foot 3. The foam plastic shall have a flame spread index of 25 or less and an accompanying smoke developed index of 450 of less when tested in accordance with ASTM E 84. " You can submit a code change for thicker applications in the next code cycle or provide the code official with test data that demonstrates that thicker applications of open cell foam would have the same fire characteristics as the 3 1/4 inch application. ASk your supplier if they tested the foam at thickner applications.
Posted: Jun 05, 2009 06:41 AM	i submitted es report showing testing to 6" with less smoke and same flame,,, no go,,,it is 3.25" no more,,,live by the code,,die by the code.... SO YOU CANT GET THE NEEDED R VALUE IN THIS HIGH LOSS AREA,,YOU CANT APPLY OUT TO THE VERTICAL FACE OF THE WALL COVERING THE PLATE TO FOUNDATION INTERFACE WHERE THESE PLACES LEAK LIKE CRAZY UNDER PRESSURIZATION???? can we maybe have another study showing the effectiveness of foam roofs?????
mason Posted: Jun 05, 2009 08:06 AM	Foamdude, A code official may at his descretion accept fire tests specific to the application as an alternative to the prescriptive code. Too bad your code official did not recognize the fire testing. But many will, so keep the ES report available, it will come in handy with other code officials. You might try another run at him with the specific test again and show the section in the code on special approval. In the IRC it is Section 314.6 "Specific Approval: Foam plastic not meeting the requirements of Sections R 314.3 through R 314.5 shall be specifically approved on the basis of one of the4 following approved tests: NPFA 286 with the acceptance criteria of Section 315.4, FM 4880, UL 1040 or UL 1715, or fire tests related to actual end-use configurations. The specific approval shall be based on the actual end use configuration and shall be performed on the finished foam plastic assembly in the maximum thickness intended for use...." Your code official should know this section and be able to relate it to the ES report that shows the foam was tested and "approved" at 6 inches rather than 3.5 inches.