Any experience with XYPEX waterproofing?

[structuresguy]

I have a contractor wanting to substitute XYPEX waterproofing for a typical membrane barrier system for waterproofing my below grade elevator pits. I have never heard of this product, and it's performance seems somewhat suspicious to me. Does anyone have any good proven experience using this product? and if so, are there any issues which need to be considered in its use?

Thanks very much.

 

[hokie66]

Xypex is based on the formation of crystals forming in cracks in the concrete to seal them. So you really have to have water penetration for it to work, and it takes some time.

The Xypex specification requires concrete with a high cement content, and also a relatively high quantity of crack control reinforcement. So it is never clear whether it is the upgraded construction specification or the Xypex additive which is actually making the structure better in resisting water penetration.

I have on several occasions been asked to investigate leaking decks, usually above carparking areas below, which have depended solely on Xypex or similar for watertightness. I have usually found direct tension cracking which the Xypex had no chance of sealing.

There is no substitute for stopping the water at the outside surface. No matter what you do, concrete is not usually a truly watertight material.

However, for elevator pits, which are limited in size, the Xypex concrete with the company's specification followed to the letter may work just fine. The wall to floor joint would be the most likely point of entry, and I think they have details for that which are required to be followed. Insist on the Xypex rep giving on site service and signing off on the work. A sump in the base is still necessary.

 

[structuresguy]

THanks for the input. The architect and I are both leaning towards system we know work. The labor quality in our area is, how should I say politely, questionable. So using new products, or some new technique, is almost out of the question.

Heck, the main concrete supplier in the area (Rinker) can not even provide self consolidating concrete. When I asked their mix design engineer (?), he said he had never even heard of such a thing. Wow!

 

[hokie66]

Well, I have never heard of self consolidating concrete either. Rinker is one of the largest concrete companies in the world, so you might get the idea that it is not very common. Why would want such a thing?

 

[dik]

I've used Zypex for years and it works well for sealing small, non-dynamic cracks.

Dik

 

[concretemasonry]

XYPEX is not a new product and has been around for at least 25 years, as I recall. Self consolidating concrete may only be new to the U.S.

Rinker is a good company, but it is just a regional company that has been purchesed several times in the past 10 years. Because of the international vertical integration and increased emphasis on technology, I think they will be able catch up quickly.

My experience with XYPEX is that it can make conrete better by filling the voids with crystals that inhibit the movement of moisture. If there are large voids due to poor placement, mix design or cracks (micro or visual) the performance is seriously reduced.

Can the contractor proposing the XYPEX cite any specific projects where he has used it sucessfully including the conditions, concrete supplier and mix designs?

 

[structuresguy]

Thanks for the additional info on Xypex. I have already asked the contractor to provide examples of local successful applications, preferably installed by their sub. So far I have not received anything from them.

My comments on Rinker were not meant to reflect Rinker as a whole, as I think they generally do a decent job with "normal" products, but rather the local construction industry. If I were in Miami or Atlanta, I expect Rinker could produce SCC. But here things are....different. We get home builders winning $50 million dollar condo projects. The quality of the labor we see on a daily basis is poor at best, appalling at worst.

I was even at a local seminar hosted by Grace and Rinker, where the topic was SCC. The Rinker rep was not local, nor was the Grace Rep. After they gave their talk, where they said SCC was such a great product and currently available from Rinker. I asked them why then could the local supplier not provide it, let alone even hear of it? I really stumped them both in front of about 100 other local engineers and building officials. Even after this seminar, by about 6 months, Rinker still could not provide it locally.