waterproof concrete
waterproof concrete guarantee STOP PRESS
2017 World of Concrete show, Las Vegas, January 2017.

Kevin Yuers
VP Product Development
recognised my name badge and we debated for some time.

He FAILED to impress.
My report at the bottom of the page.

Kryton KIM (Krystol Internal Membrane)

As you see in their warranty above, from the bottom of their Technical Data Sheet reproduced here, they accept no responsibility at all.

Yet, if you click on my image of their TDS, it starts by calling their product Waterproofing Admixture for Concrete.

Let's see

Krystol Internal Membrane - HS (KIM-HS) has a BBA certificate that states that it is a reactive crystalline admixture, contains blended Portland cement and fine quartz sand.

View the certificate here.

So it seems to have copied Xypex.

It even tells you to buy C35A watertight concrete, the same as Xypex.

However a little more Krystol is used, 6.5 kg compared to about 4 kg Xypex. But that will probably be the sand.

And, somehow, the results for water permeability are far more impressive. The results for water vapour permeability are rather more subdued.

Just like the Xypex BBA test results, the test concretes both had slumps after 30 minutes that would be intolerable on site. Water would have to be added if the journey and the time needed to pump the concrete into any wall totalled more than 30 minutes, which it almost always will.

So it is the usual smoke and mirrors and no evidence that on site similar results would be achieved.

Indeed, the technical data sheet makes the point that on site you should not expect the increase in strength that they got at BBA.

waterproof concrete

The 2017 World of Concrete show in Las Vegas was enormous with almost 1600 exhibitors.

During my second day I asked at the Kryton stand about surface densification (which means applying cement to finished concrete to improve the surface). The guy on the stand kept on and on about crystal growth, making it sound magical rather than something that happens anyway.

He also promoted Kryton KIM in the concrete as the way not to need to repair the surface, because it waterproofed the concrete. He claimed that if the concrete cracks their chemical will penetrate several feet into concrete and fill voids.

My response would be that they produced a crack in a test situation that made this true just once in a laboratory. Perhaps the crack was deliberately wide narrowing to nothing and from the top down so that gravity did most of the work when they filled it with more KIM concrete.

It must have been a test sample because I shouldn't think they ever had a customer with KIM treated concrete several feet thick.

I challenged him once that everything he said about crystal needles was describing the hydration of cement, but he ignored it and ploughed (plowed) on.

However someone else read my name badge and said 'I know that name'.

He turned out to be
Kevin Yuers Kryton
We spoke for a long time, and he acknowledged:
  waterproof concrete guarantee

Those naughty boys at Kryton.

This quote is from their technical data sheet. Click on our image of their TDS to find the original on their website.


Krystol Internal Membrane (KIM) is a hydrophilic crystalline waterproofing admixture in dry powder form. KIM is used in place of externally applied surface membranes to protect concrete structures against moisture transmission, chemical attack and corrosion of reinforcing steel.

When combined with fresh concrete, Kryton’s unique and proven Krystol® technology reacts with un-hydrated cement particles to form millions of needle-like crystals. Over a period of weeks and months, these crystals grow, filling the naturally occurring pores and micro-cracks in concrete, and permanently blocking the pathways for water and waterborne contaminants. Later, if cracks form due to settling or shrinkage, incoming water triggers the crystallization process and additional crystals form, filling cracks and ensuring that the structure’s waterproofing barrier is maintained and protected.

In addition to filling the pores and capillaries of the concrete matrix w ith crystals, KIM enhances the natural hydration process by intensifying and prolonging the hydration of the cementing materials. This reduces the size and number of cracks and capillary pores within the concrete matrix, making it dramatically les s porous, and improving strength and durability characteristics.

All this description is describing is OPC.

And their BBA certificate states that Krystol Internal Membrane contains OPC and sand.
  1. KIM contains cement

  2. KIM contains sand that does nothing to aid waterproofing

  3. KIM contains other stuff that are active ingredients, but he did not say they are waterproofing chemicals

In fact he said that without the sand they would have trouble mixing the KIM cement into the mix.

Sadly, I did not ask 'why should that be?' given that the cement in KIM is added at the same time as 350Kgs of OPC at the plant.

Afterwards it occurred to me that the sand might be in the bag just to break the bag open quickly enough. Because if the bag did not break open quickly enough they would have trouble mixing the KIM cement into the mix.

He described the sand as necessary and a part of the mixture to make KIM foolproof in use all over the world, including Africa. So he seemed to have worldwide responsibility.

We discussed cracking and voids in concrete. He said they have a lot of problems because of poor workmanship.

May I refer my reader to the guarantee quoted at the top of this page. They categorically do not guarantee against leaks through cracks and voids.

He said to me, unprompted, that readymix producers would all tell you that they can produce a waterproof concrete without an admixture like KIM. Said in a way that he knows it to be true.

The reason I say at the top of this page that he failed in our debate is that his knowledge of cement and concrete was weak and he stated as facts several points that are simply untrue - and I was able to tell him in what sources he could find the truth.

He said:
  1. Concrete is getting stronger for ever. Not true.

    I appreciate that is the kind of thing that was taught to 17 year olds in a college, but academic sources disagree.

  2. We were talking about flash setting, and he said that it would be a problem with gypsum in a way that suggested he had no idea why there is 5 per cent gypsum in all OPC, in the UK anyway, to give the site 2 hours working time, and

  3. He said that only about 30 per cent of cement reacts in concrete, leaving about 70 per cent unreacted.

    This is not just untrue, not even just a schoolboy error. This is an absolute crime from someone in his position because it is designed to mislead.

    Why would he say it?

    I think he says it so that his sales staff tell prospective customers that the left over cement will heal cracks. This is called autogenous healing.

    Our own BS 8110 says that crack widths restricted to 0.2mm can autogenously heal.

    However, how much cement reacts is largely due to the water cement ratio. With very limited water it might be true that only 30 per cent of the OPC reacts. But one of the books I have suggests that with over 80 per cent water to cement all the OPC will react.

    And our own BS 8110 explains that there needs to be extra reinforcing steel to control the crack widths to what will heal.

    But he made the claim that Kryton KIM concrete heals 0.20mm cracks, which is their claim, and even 0.50mm cracks though they don't publish that as a claim. But I bet their sales people say it.

    Then he was telling me that in North America they usually Value Engineer the design and reduce the reinforcing steel as far as possible, which means they don't have enough steel to control crack widths to 0.2mm.

    He also said that they often find that customers pour concrete badly and that when they have honeycombing at the bottom the hydrophylic strip they sold them does not work.

    So whilst his concrete, like any other with 350Kgs of OPC and only 0.45 water by weight of cement, will autogenously heal cracks up to 0.2mm, it is clear that they don't often insist there is enough steel for that to happen.

    Most of the time it must be untrue of KIM concrete.

    So I think that his claim is designed to mislead his potential customers - in other words I think the tale they tell, as a whole, is a lie with intent to mislead.

  1. Kryton staff lie. Perhaps management selects the truth in their staff training to such an extent that what they claim is not, strictly speaking, false. But then their staff find their own form of words and the message given to the public is untrue and misleading. Management will be well aware of this which is why their guarantee (above) states that nothing said by a sales person counts for anything.

    Kryton KIM contains nothing that is not cement to waterproof concrete. Any waterproof results are from crystals of hydrated cement in a reduced water to cement concrete mix.

    All KIM is doing is increasing the cement already in the mix from at least 325Kgs by about 1%.

    And it retards the set, so the concrete user could ask his concrete supplier for 1% more cement and some retarder and get the same thing virtually for free.

  2. Kryton do not warrant against any kind of leak and by his own admission the finished concrete structures often leak.
This was a debate with an executive of the company. I imagine that he started it expecting to do better.

The Kryton KIM bag states, at the very top "TAKE THE RISK OUT OF CONCRETE WATERPROOFING"

Nothing Kevin Yuers said supported any truth in the statement.

Of course the customer who buys the concrete never sees the Kryton package.

It is the readymix concrete producer who buys the KIM and puts it in the concrete he sells.

Quite clearly, the instructions to the readymix producer are to keep the water cement ratio reduced to 45%, and he is told on the pack that KIM contains a retarder.

Kryton KIM

You can click on the image above to open the original photo in a new window and read the instructions for yourself.

Kryton KIM