Posted By Aaron Ayer on 19 Feb 2010 02:56 PM

Solutions companies such as Hycrete do the bulk of their work through as systems approach - Hycrete System W, for example - that cover all these elements.  The systems approach incorporates 3 major elements, then - waterproof concrete from the admixture, waterproof construction through the service element (ensuring sealing of joints, maximizing concrete quality, and repairing the inevitable cracks), and a comprehensive performance warranty.

The traditional approaches require membranes.  Membranes are a Bandaid employed to keep water AWAY from the concrete, where the real objective is to keep water away from the OTHER SIDE of the concrete.

Aaron,

Thanks for the response.  You mention some of the elememts that I was indirectly fishing for.  The issue in all of this is how to do the detailing at penetrations, curbs, perimeter flashing, expansion joints, etc. in addition to the cracks.  To me, this is the weakness of Hycrete/Xypex type solutions and to a slightly lesser degree with bridge and deck coatings.

I think it is important to note that any roofing or waterproofing solution needs to keep water out of the structure itself as well as from the "other side".  Most of these produts have highway/heavy construction origins to protect structural integrity, rather than in a "roofing" situation.

In my day job, if we have a project using diaphragm (slurry) walls in a high water table environment, we do all we can to make a watertight wall, but we are also prepared for the inevitable leakage/seepage.  I do not want to deal with leakage or seepage in the flat, concrete, extensive green roof I hope to use in the build for my new house.

BTW, if Steve Crawford is still with you, give him my best.

Chees,

Bruce

Supposedly, adding MgO to concrete can get rid of the shrinkage. MgO expands, normal concrete shrinks and the right mix stays the same - might be better than glass fibers.

Thanks for the reply, Bruce. You are right - the "devil is in the details". Getting the details right is a core part of our business; we have to tackle that every day.

And, like any prudent supplier in the construction world, we need to know when to say, "No" - when the project isn't a fit, the risk is too high, etc. We're a great product / solution to be used belt-and-suspenders for green roofs, but since we can't access a surface for closure work, we wouldn't recommend using us as the sole solution.

Aaron