Archive through October 29, 2010

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Author Message Dale Hurttgam, NCARB, AIA,LEED AP, CSI Senior Member Username: dwhurttgam Post Number: 65 Registered: 10-2005 Posted on Wednesday, October 27, 2010 - 09:42 am:    We have a project where we specified wood paneling with a veneer faced MDF FR core. The project architect has now heard that there is a potential for discoloration of the wood veneer due to the fire retardant treatment on the core and also that if the paneling has "scores" that deterioration may result along the score again due to the fire retardant treatment. So far, I have not been able to locate information documenting this concern. Has anyone heard similar concerns or experienced a problem of this nature? Anne Whitacre, FCSI CCS Senior Member Username: awhitacre Post Number: 1033 Registered: 07-2002 Posted on Wednesday, October 27, 2010 - 01:14 pm:    I am aware of this, but not actually had a problem with it. Generally I specify that the panel fabricator has to demonstrate that there will be no discoloration due to the treatment and that the panel has to be warrantied for that. Never had a problem getting that warranty -- the panel suppliers are aware of what works and what doesn't work. This is an old issue and to my knowledge, not a problem with the newer treatments. John Bunzick, CCS, CCCA, LEED AP Senior Member Username: bunzick Post Number: 1258 Registered: 03-2002 Posted on Wednesday, October 27, 2010 - 02:30 pm:    Also, check the American Forest and Paper Association publication about fire characteristics of wood. Most species on plywood will meet a Class C rating without fire retardent core. Class C may be fine for many locations within a project. Ronald L. Geren, AIA, CSI, CCS, CCCA, SCIP Senior Member Username: specman Post Number: 882 Registered: 03-2003 Posted on Wednesday, October 27, 2010 - 02:44 pm:    To add to John's comment, when a higher classification is required, there are fire-retardant finishes that will provide up to a Class A rating. Ron Geren, AIA, CSI, CCS, CCCA, SCIP www.specsandcodes.com Dale Hurttgam, NCARB, AIA,LEED AP, CSI Senior Member Username: dwhurttgam Post Number: 66 Registered: 10-2005 Posted on Friday, October 29, 2010 - 09:48 am:    Thank you for your responses. I spoke to a quality local millwork shop that confirmed that they had not experienced problems of this nature, and that it may have been a problem from the distant past. They noted that certain fire retardant treated wood products had experienced problems in the past due to being used in inappropriate locations. These products were heat sensitive and had problems when used as roof decking or for trusses. They also cautioned about using wood veneer panels in areas where exposed to UV. I was about to put it to rest, until I spoke to a representative of a MDF FR product manufacturer. From information that I received from him, the veneer discoloration problem is a more recent issue and has to do with changing formulations of fire retardant treatments and glues to be more environmentally sensitive. It is also limited to certain veneers that have sensitivity to heat and/or certain new adhesives. He indicated that in recent years there were some changes in the formulation of chemicals used for fire retardant treatment. Also there have been ongoing changes in the formulation of glues/adhesives used. These are the cautions that he provided: 1. Discoloration problem is limited to certain veneers. The two veneers that he was specifically aware of – white oak and eucalyptus. These veneers have sensitivity to certain adhesives and to high heat. 2. He indicated that if polyvinyl acetate glues are used for the veneers that they should not be low ph. 3. He also indicated that the panels should be cooled quickly after having the veneers applied. There is a problem with “high stacking” the panels before they are cooled – if they are stacked before cooling, the heat tends to intensify before it dissipates which accentuates the problem with heat sensitive veneers. With respect to checking or crazing or other deterioration concerns at score lines, the representative had not heard of any such problems. There has not been a “technical bulletin” released on this concern although one has been prepared for consideration and review. Dale Hurttgam, NCARB, AIA,LEED AP, CSI Senior Member Username: dwhurttgam Post Number: 67 Registered: 10-2005 Posted on Friday, October 29, 2010 - 11:10 am:    I also just discovered the following on a spec data sheet for another manufacturer's MDF FR product: USAGE NOTES Some laminates and coatings applied to "XXXXX" FR MDF may change the flamespread rating. Standard available woodworking glues have been successfully used in lamination. Any adhesive should be tested for compatibility with the chemical system in "XXXXX" FR MDF prior to full-scale gluing. Questions should be directed to the glue supplier. Wood veneers and other laminates should be tested for compatibility with "XXXXX" FR MDF products prior to use. Some species of wood veneer may have reactions to select combinations of surface coatings, veneer glues, pressing temperatures and the chemical systems used to manufacture FR MDF products. Reactions may include slight discoloration to veneer. "XXXXXX" is investigating solutions, but until trials are complete, we will not be responsible for claims associated with discoloration. Please contact your Sales Representative for more information.