In what is a probable precursor to Crossfield Products Dex-O-Tex introducing a metal lath system, the magazine of
www.Concrete Network.com has an article in their most recent issue.
Written by Bill Palmer, a Concrete Network columnist, the article covers a demonstration of the install procedure done at the American Society of Concrete Contractors convention in North Carolina last fall.
A couple of criticisms, the article glosses over the install procedure, making it seme very simple and with the exception a couple of "watch out for's" would make one think after reading the article that they could just go out and do themselves. That's deceiving, because this is a concrete magazine, not a waterproofing magazine and waterproofing is wholly different from concrete decorative overlays.
Miracote rep Trevor Foster is quoted as saying that "flashing is one of the critical elements to making the system work." No Trevor, flashing is the number one critical item to making the deck waterproof. Period. No argument.
The Miracote system as a direct bond system is an interesting install procedure...
The first step is to install the metal lath with 22-28 staples per square foot (the more the better, some systems call for only 15-20) then, prior to troweling in cement into the lath, they prime the lath and plywood with a diluted polymer resin first. Then they Mirecote RM III polymer-modified concrete underlayment fills the lath. Two coats of single component fluid applied waterproofing is then applied at 25 mils wft, drying to 12.5 mils. (Sounds like a Tufflex type product to me)
They say nearly any sort of docorative overlay can be placed over it and at the demo did a 1/2" topping of Miracote's MPC.
I have several concerns and/or questions to get myself answered; one being why the primer of polymer to the lath and plywood? Are their adhesion issues with their cement to the lath and plywood without that step... or is their something they see as advantageous to that step over their competitions methods? Hmmm. Then I do have an issue over the 1/2' of stamp mix-maybe on smaller decks that will work without much cracking, but what about larger decks with a long span of joists. How will they prevent cracking the stamped surface?
Other questions come to mind too such as fire ratings, ASTM testing and such if any has been done and how proven is the system? If it's new, Miracote will need to show why this should go down in lieu of tried and true decking systems.Showing it to a convention of concrete contractors who probably don't understand the nature of waterproofing at all isn't a good move in my mind...Miracote is looking to open new markets up and needs to spend a lot of time making sure their new market can do the waterproofing part of the job.
