This from Kevin. Please read. ________________________________ From: Kevin Sloan [mailto:ks@kevinsloanstudio.com] Sent: Tuesday, August 25, 2009 12:02 PM To: Bruce Dunne Cc: Robyn Jacobson; Diane Sloan Subject: KSS Stone Recommendation Dear Bruce, We understand that stone has been requested by the Town of Addison as a decorative veneer over concrete walls. I want to go on record with some concerns about the material and some recommendations. We have not recommended stone, either as a veneer or as load bearing walls, because, although stone can be an extremely attractive choice, it is the least sustainable finish, mostly due to the fact that there are no quarries in Central Texas that produce stone, much less a stone type that is dense enough to resist the flooding and staining that will occur in the park. Limestone or sandstone are very porous and would discolor after each flood. As time passes, the project can become unattractive as the watermarks and staining accumulate. Power and acid washing could be necessary after each flood. The stone has to be able to withstand the flooding both technically and aesthetically, or the veneer will fail. In addition, it is an expensive material, on par with or more so than brick. We also have a concern about water collection between the stone veneer and the structural concrete wall. Typically weeps are introduced in a veneer wall to drain water that finds its way into the cavity space behind the system. Given the unique situation of the floodway, this veneer will have to be designed to allow the water to do the opposite - move through the veneer into the cavity space, then drain out when the floodwaters recede. There is no waterproofing that can prevent floodwaters from entering the cavity space and it would be back practice to design a veneer wall without any weeps. Over time the weeps are certain to clog from the floodwater sediments, trapping water. Once behind the wall, it has no way of draining out. All that being said, should the Town of Addison decide to use stone and the drainage detail solved, we have the following recommendations. Our recommendation would be to install flame finish granite that is horizontally coursed in uneven vertical increments. This strategy would disguise the watermarks that appear after flooding and resist staining because granite is dense. Slate is the alternative to granite. The color should be dark to discourage staining. Kevin Sloan KEVIN SLOAN STUDIO 4145 Travis, Suite 105 Dallas, Texas 75204 Office: 214.379.1061 Fax: 214.528.6296 ks@kevinsloanstudio.com No virus found in this incoming message. Checked by AVG - www.avg.com Version: 8.5.406 / Virus Database: 270.13.65/2324 - Release Date: 08/25/09 06:08:00