DensElement - Thoughts? Feedback? Exp...

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Author Message Nathan Woods, CSI, CCCA, LEED AP Senior Member Username: nwoods Post Number: 743 Registered: 08-2005 Posted on Monday, July 02, 2018 - 05:39 pm:    Looking for industry experience related to the "DensElement" product from Georgia Pacific: https://denselement.com/Home.aspx Any thoughts on this? Dewayne Dean Senior Member Username: ddean Post Number: 158 Registered: 02-2016 Posted on Monday, July 02, 2018 - 06:18 pm:    The salesman who visited our office last month was convinced that this product would transform the industry as never before Steven Bruneel, AIA, CSI-CDT, LEED-AP, EDAC Senior Member Username: redseca2 Post Number: 650 Registered: 12-2006 Posted on Monday, July 02, 2018 - 07:05 pm:    We had this specified as one of several interrelated Bid Alternates for a design-build outpatient medical office building. This one didn't make the cut. Brian Payne, AIA Senior Member Username: brian_payne Post Number: 153 Registered: 01-2014 Posted on Monday, July 02, 2018 - 07:24 pm:    A couple of thoughts... It won’t cover all conditions on most projects. You’ll probably still need fluid/sheet somewhere. It’s a pain to specify. Sheathing section doesn’t talk about waterproofing and waterproofing doesn’t talk about sheathing. Equals are limited. Might be best to specify traditional and leave DensElement as Alternate with detailed description. I like the concept Steven Bruneel, AIA, CSI-CDT, LEED-AP, EDAC Senior Member Username: redseca2 Post Number: 651 Registered: 12-2006 Posted on Monday, July 02, 2018 - 08:31 pm:    Brian, I agree that Alternates are often the best way to go. As I mentioned in my previous post, for a design-build project we had several apple to oranges systems under consideration: Dens Element, per this discussion. A proprietary Z-girt and rigid insulation system A proprietary Momentive (GE Silicons) barrier system. Generic peel and stick membrane, and/or generic fluid-applied membrane Generic rigid insulation Generic Z-girts Generic Mat-faced sheathing A rather lengthy Bid Alternates Section defined which of these went together with the rain screen cladding in various Bid Alternates to provide a complete exterior enclosure system (Choose one from column A; One from column B...). As you suggest, you could never completely dispense with the generic products, particularly peel and stick products. There is also the problem of these proprietary combinations not having an obvious home in the Masterformat names and numbers. If the manufacturer suggested a name and number we used it. Not something I would normally do automatically, but a bidder familiar with the system might also be familiar with the name and number the manufacturer provides. The project was in a very dry southwest location which lessened some of our worries. In the end, the entirely generic products were selected. Michael Chusid, RA FCSI CCS Senior Member Username: michael_chusid Post Number: 402 Registered: 10-2003 Posted on Monday, July 02, 2018 - 09:04 pm:    Nathan, What are the perceived benefits of Dens Element that have attracted your interest? Michael Chusid, RA FCSI CCS 1-818-219-4937 www.chusid.com www.buildingproduct.guru Nathan Woods, CSI, CCCA, LEED AP Senior Member Username: nwoods Post Number: 744 Registered: 08-2005 Posted on Monday, July 02, 2018 - 09:46 pm:    Michael, primarily its because I hadn't heard of it until a contractor asked if he could use it. In my circumstance, it is for temporary protection of an opening in an exterior wall (healthcare facility). It seems well suited for that. For a permanent assembly... I'm not so sure. There is no limitation of exposure that I can find in the literature, though i seem to recall DensGlass having a 6 month exposure limit. Or maybe 12 month, but not longer. On some projects, the skin (rainscreen assembly) may not be added for more than 6 months. In that circumstance, this would not be a good idea. I'd also like to follow the migratory path of vapor and moisture around the joints, and if moisture builds up on the inside face of the sealant over time.... Greta Eckhardt Senior Member Username: gretaeckhardt Post Number: 76 Registered: 08-2013 Posted on Tuesday, July 03, 2018 - 10:19 am:    Please disregard my previous post if you received it - I had not yet seen some of the detailed product data available, and would like to revise my comment as follows: I had not heard of this product before, but Tremco and USG have also collaborated to produce a factory-applied, vapor-permeable air barrier membrane (Tremco Exo-Air 430) on glass mat-faced Gypsum sheathing (USG Securock) and it too is marketed with the necessary joint and penetration treatment. I definitely like the basic concept of factory application of the air barrier. The Georgia-Pacific Denselement appears to have some of the same advantages of factory-application of a membrane, but instead of placing it on the surface of the board, it is a layer between the glass mat and the gypsum core of the board. I have a couple of comments after reading some of the product data: 1. This product has passed ASTM E136 testing for noncombustibility, and the product data claim that engineering calculations have been performed showing compliance with NFPA 285. It seems likely that the barrier material is a polymer and I would be more comfortable specifying it if I saw test reports showing it had actually been included in exterior wall assemblies that pass NFPA 285. 2. By placing the air barrier material within the core, it will not be in contact with the tape materials used for joint treatment so in a sense the air barrier would not be perfectly continuous. I would want to see results of an assembly test for air tightness that showed that joints do not leak, not just a product test. If these concerns could be addressed, I can imagine preparing a Section 061643.13 - Gypsum Sheathing with Integral Water-Resistant Air Barrier or something like that, and name both the Georgia-Pacific/Prosoco and USG/Tremco systems. J. Peter Jordan Senior Member Username: jpjordan Post Number: 1046 Registered: 05-2004 Posted on Tuesday, July 03, 2018 - 10:26 am:    i first heard of this about two years ago and expressed some skepticism that it would indeed be less expensive. I think that the product itself is OK, but as with a good many products, the devil is in the detail with joints and penetrations needing detailing. I initially told the rep that I would not oppose a substitution request, but I was not going to specify it right away. We have now specified it twice at the request of the Owners' contractor. Many people may not know that the standard for air permeance for an air barrier is based on uncoated DensGlas Gold. The air barriers that we apply are more "air and water barriers" which enhance the ability of this plane to withstand water infiltration (as well as air infiltration). The gypsum sheathing products add the AWB at the factory; joints and penetrations still require detailing. The advantage that these products have over the ZipWall product is that the substrate is gypsum rather than OSB. Some jurisdictions will not allow the OSB in Type II or Type I construction. The treated gypsum core is also more resistant to damage from water infiltration than is the OSB. Two manufacturers now offer the air-barrier and water-resistant glass-mat sheathing: Georgia Pacific (DensElement) and USG (Securock ExpAir). GP has teamed up with Prosoco and USG has teamed up with Tremco. I believe the sheathing manufacturers will require use of respective coating manufacturers to obtain any sort of warranty. The latest version of MasterSpec's sheathing section include requirements for both products including performance and field quality control requirements. Since I am still not convinced of savings, I will continue to specify it only upon request of the Owner or recommend approving it as a substitution request. J. Peter Jordan, FCSI, AIA, CCS, LEED AP, SCIP Ronald J. Ray, RA, CCS, CCCA, CSI, AIA Senior Member Username: rjray Post Number: 179 Registered: 04-2004 Posted on Tuesday, July 03, 2018 - 10:39 am:    Both ASHRAE and IECC consider “standard” 1/2 inch thick exterior gypsum sheathing board an air barrier. Whether that would include such “new” gypsum-based products as discussed here, would perhaps need to be verified with ASHRAE or IECC. Of course, that does not address a need for a water-resistant barrier. Ronald L. Geren, FCSI, AIA, CCS, CCCA, CSC, SCIP Senior Member Username: specman Post Number: 1503 Registered: 03-2003 Posted on Tuesday, July 03, 2018 - 11:45 am:    Thanks, Ronald, I was going to mention that. People tend to conflate air barriers and vapor retarders. Gypsum board is an air barrier, but it is not a vapor retarder (by IBC definition, at least). The concern, as you state, is whether or not it's an effective water-resistive barrier. If ICC-ES has accepted it (which it has: ESR-3786), then I would be willing to accept it as well. Ron Geren FCSI AIA CCS CCCA CSC SCIP www.specsandcodes.com Chris Grimm, CSI, CCS, SCIP, LEED AP BD+C Senior Member Username: chris_grimm_ccs_scip Post Number: 407 Registered: 02-2014 Posted on Thursday, July 05, 2018 - 08:46 am:    At a recent conference, the question was raised whether a DensElement board appears any different from a DensGlass Gold board so field personnel can verify whether the right product is being used. I believe the GP website answers this question. There is a DensElement logo on the board. Brett Scarfino (Unregistered Guest) Unregistered guest Posted on Thursday, July 05, 2018 - 11:00 am:    I saw it once a few months back at an AWB "hands-on" event, and have a sample in my office. It looks and feels nearly identical to DensGlass, aside from the logos. I'd ask manufacturer(s?) what to do with fastener penetrations. Edward J Dueppen, RA, CSI, CCS, LEED AP Senior Member Username: edueppen Post Number: 46 Registered: 08-2013 Posted on Thursday, July 05, 2018 - 12:58 pm:    I too have been highly skeptical of this product type, but am gaining some comfort from some limited experience with them. Twice now we have received and approved requests from contractors to use this type of system - a hotel in Colorado and another in Wisconsin. The hotel in Wisconsin was a high-rise in a tight urban infill. We specified fluid-applied air barrier, but the contractor was very concerned about overspray and logistics, so we approved the change. To emphasize the air barrier nature of the product, I have specified it as Section 07 2723 - Gypsum Sheathing Air Barrier Systems. I have also seen this type of product used in modular construction. A local general contractor was panelizing exterior walls with the sheathing applied to CFMF. The fasteners and joints in each module were treated in the shop, so only joints between panels would need to be treated in the field. An advantage I see to the DensElement product is that the air barrier layer is protected by the outer panel facing. The USG product is on the panel face, which leaves it more susceptible to damage. But I consider the systems comparable enough to make for competitive bidding. Edward J Dueppen, RA, CSI, CCS, LEED AP Senior Member Username: edueppen Post Number: 47 Registered: 08-2013 Posted on Thursday, July 05, 2018 - 03:31 pm:    I should add that I have a sample of each product on my desk. I'm not sure if the samples are truly representative of the actual product, but I did notice the following: The membrane on the USG product seems to peel rather easily off the core, while the DensElement sample cannot be delaminated. John Bunzick, CCS, CCCA, LEED AP Senior Member Username: bunzick Post Number: 1748 Registered: 03-2002 Posted on Friday, July 06, 2018 - 04:04 pm:    The manufacturer has a few videos of installation. Fasteners must be treated with the same "sealant" as joints, that is tooled flat.