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Author Message Russell W. Wood, CSI, CCS Senior Member Username: woodr5678 Post Number: 91 Registered: 11-2003 Posted on Friday, June 22, 2007 - 08:53 am:    I'm working on a Lightweight Insulating Concrete spec. In addition to cellular-type my Architects want me to specifiy aggregate-type too. However, Masterspec says vermiculite aggregate-type may contain asbestos. We're considering Siplast's NVS (non-vented system) lightweight that uses vermiculite aggregate..I've spoken to Siplast and they swear it's been years since they mined any vermiculite with asbestos. Does anyone know? Richard Howard, AIA CSI CCS LEED-AP Senior Member Username: rick_howard Post Number: 138 Registered: 07-2003 Posted on Friday, June 22, 2007 - 02:58 pm:    Vermiculite often occurs naturally with asbestiform minerals. However, after the dust settled from asbestos litigation, the vermiculite producers have really tried their best to mine deposits where trace amounts of asbestos and related minerals are not present. You can go to www.vermiculite.org to get the industry line on the subject. Many people were burned by specifying vermiculite products that contained trace amounts of asbestiform minerals and still feel strongly that vermiculite is suspect. I can't say I blame them for feeling that way. With the potential for materials coming from China or someplace else where testing is not employed to verify the purity of the product, buying from reputable manufacturers is an important safeguard. Anne Whitacre, FCSI CCS Senior Member Username: awhitacre Post Number: 577 Registered: 07-2002 Posted on Monday, July 02, 2007 - 05:09 pm:    also: see if the vermilculite form is even available. I tried specifying it a year ago and no one would provide it -- nor could I get a roof warranty when it was used as the deck. it sounds like a lot of folks are still gun-shy after the asbestos issue. Russell W. Wood, CSI, CCS Senior Member Username: woodr5678 Post Number: 94 Registered: 11-2003 Posted on Tuesday, July 03, 2007 - 09:28 am:    We're specifying a Total System Warranty for our roof system (mod-bit membrane(s) over lightweight insultating concrete on a metal deck). We are hearing that membrane manufacturer's (Firestone, GAF, Manville, etc.) wiil not warrant the "system" if Siplast is the LWIC supplier/installer. Is this true? Anonymous   Posted on Tuesday, July 03, 2007 - 11:08 am:    Siplast's parent company is Carlisle so they want you to use their membrane if not Siplast's. It has been our experience that Siplast will not indemnify other membrane manufacturers. So what you've heard above to my opinion is probably true. Jerome J. Lazar, RA, CCS, CSI, SCIP Senior Member Username: lazarcitec Post Number: 392 Registered: 05-2003 Posted on Tuesday, July 03, 2007 - 12:22 pm:    Russell remember to specify the surface conditioner that is applied over the insulating concrete, we just went thru this on a project as there was confusion as to who is responsible to apply it. In the case of Celcore's product, Celcore calls it a "Curing Compound" and provides application instructions that should be included in the spec section, even though it does not appear in their recommended spec section. Russell W. Wood, CSI, CCS Senior Member Username: woodr5678 Post Number: 95 Registered: 11-2003 Posted on Monday, July 09, 2007 - 04:59 pm:    Anne, Siplast makes several aggregate type LWICs w/ vermiculite...Zonocel & NVC. Bill Morley Senior Member Username: billm Post Number: 18 Registered: 08-2005 Posted on Thursday, August 09, 2007 - 06:56 pm:    Isn't there also an issue with the vermiculite retaining water? There is one type of LWIC that is considerably more prone to moisture vapor problems due to the aggregate, and I thought that was vermiculite.