waterproof concrete

Waterproof Concrete.


  1. You buy the readymix concrete.

  2. We waterproof it when it arrives on site.

  3. We supervise your pour.

  4. You pour it, compact it and cure it.

  5. We repair any visible leaks later free of charge.


  • We supply the necessary chemical to make your concrete completely waterproof.

  • We supply the supervision to ensure good practice and avoid mistakes.

  • We hire you vibrating pokers that are powerful and work properly.

  • We will repair any visible ingress of water later free of charge.

  1. £23 per cubic metre of concrete treated.

  2. £300 a visit supervision and training.

  3. £80 per pour poker hire. Poker to use and a spare.

  4. Fibreglass threaded rods, big nuts and thin nuts: £2.50 per m, £1.50 each and £0.30 each.

  5. We repair any visible leaks later free of charge.

That means we are guaranteeing the workmanship of people who do not work for us, as long as they do as they are told, obviously.



  Please note. The author acknowledges all the trademarks it mentions on this site.


CALL ME

Phil Sacre

Basement Expert

01438 900303

07773 377087

philsacre@
basementexpert.co.uk

 


We are different.

We waterproof the actual concrete you used on site and get samples tested at the lab to prove you used completely waterproof concrete.

We are different because:

Following the revelation that the cladding sadly used on the Grenfell Tower had a BBA certificate and had passed a BBA fire test, we analysed the BBA certificates of all the well-known brands of water-resisting admixtures: e.g. Caltite, Pudlo, Sika, BASF, Xypex and Kryton.

Analysis of their BBA certificates revealed that all of them either had not tested readymix concrete or do not work.

Most had not tested readymix concrete and did not work either.



Throughout the EU, concrete is made to BS EN 206-1 and hardened concrete is tested to BS EN 12390.

Part 3 is the test for compressive strength.

Part 8 is the test for impermeability.

Your engineer will specify C35 or C40 etc.. That is the compressive strength of the concrete and this is the test to prove that your concrete is adequate.

To be classified impermeable, depth of penetration of water under 4 bar pressure maintained for 96 hours must average 20mm or less.

We have had many successful tests for compressive strength and water permeability under pressure to BS EN 12390 parts 3 and 8.

Click on either image below to see two original test certificates.

concrete compressive strength report to BS EN 12390 3                        concrete permeability report to BS EN 12390 8


 

The choice is:

Do you carry on using an expensive product because it has a BBA certificate despite the BBA certificate proving nothing.

Or do you use us and we get your concrete tested and prove you used waterproof concrete?




 



The concrete mix you will need to buy is
  1. P350. This means 350kgs of cement per m³.

  2. CEM 1, pure OPC, or pure OPC and a blend of GGBS, slag.

  3. Over-sanded for pumping.

  4. Target slump 60mm.

  5. No other additives. Tell the readymix concrete supplier you are having a powerful plasticiser added and mixed in on site.


  1. You order and pay for the concrete.

  2. You pay us for threaded rods, nuts, waterproofer, training, supervision and poker hire.

    Our products and services ensure complete success. If you accept our methods and buy all we recommend you get the free leak repair guarantee.

  3. You pay us for testing to BS EN 12390 if you wish. £780 including VAT at the lab, mould hire etc..

  4. Note.
    In hot weather, or if the concrete needs to make a long journey, CEM 1 pure OPC can set too fast to get a good finish. OPC blended with GGBS will give you more time, though in most cases you will not need it.

    Most projects do not need sulphate resistant concrete. If your does, CEM 1 with this much cement is usually resistant to DC class 2. A GGBS blend might be completely resistant to DC class 4. Check with your readymix supplier.






In 2011, the new edition of a long-respected university text stated more clearly than ever before that completely waterproof concrete could be produced without admixtures.

"concrete with a low water/cement ratio ... make the capillaries discontinuous"
Neville, A.M. (2011). Properties of Concrete. 5th ed, p330. Harlow: Pearson Education.


In 2013, the UK's Concrete Society published a report by a working group of 18 members, experts in their fields, that states:

" water/cement ratio .... primary measure of water penetration and hence the durability of the concrete."
The influence of integral water-resisting admixtures on the durability of concrete. P36. Concrete Society. 2013.



The Concrete Society had the idea to plot the various data on BBA certificates onto one chart. I have plotted the same data here, as well as a few educated guesses where marked.

from Processes, water retaining BS EN 12390 8   Here I have plotted the before and after figures for compressive strength and water permeability from the BBA certificates I found for water-resisting admixtures for concrete.

What is striking is how varied the results for concrete without admixtures and how limited, in comparison, the benefit of a water-resisting admixture.

Some data was missing, such as Caltite compressive strength test results, so I have made up missing data with my educated guess.

This chart proves how little difference all the water-resisting products make, compared to the huge difference that a better concrete mix design can make.



The 'active' ingredient in Xypex, Krystol and Triton is only OPC. Cement. At about 100 times the usual cost.



If you click on the chart it will open in a new window so you can print it.


Have BBA conned you and not tested any of these concrete admixtures on site concrete?

To pump any concrete on site it needs a slump of at least 70mm. But the workforce would complain if the concrete was that stiff and add water (which would ruin any waterproofing and void any warranty) so concrete used on site needs a slump of at least 100mm.

But as this chart of data from the various BBA certificates shows, most brands seem to have cheated in the lab, proving that they did not test concrete that would be used on a building site.

These are the quoted figures on these brands' BBA certificates for the slump in the concrete with the admixture after 30 minutes, which is about how long a truck takes to batch, drive to site and manoeuvre into position. I have also put the cement content for each and for C35A.

Pudlo Sika BASF Xypex Kryton Krystol KIM C35A
45mm 40mm 135mm 35mm 45mm  
350kgs 350kgs 350kgs 325kgs 325kgs 325kgs


Reminder. BBA testing of Caltite did not make any concrete more resistant than a plain structural concrete, neither did they quote as many figures on their certificate as the other brands shown above.

I used to buy from BASF before I went to Asia and bought the best available there. In my opinion, the slump figure for BASF - the only one tested in concrete that could be used on site - supports the science that a quality plasticiser is all that needs adding to high quality concrete to make it waterproof.



Caltite's guarantee, you will find one pictured on this web site here, guarantees that if their product fails they will put things right (but only to the value of their product).

But what does their product do? They don't say anywhere. Therefore no one could sue.

They seem to guarantee only the product but they promote 'the system'.

'The system' includes concrete with extra sand and cement and less water. So 'the system' will work because the concrete works.

Specifiers seem led to believe that the Caltite rep on site supervises.

But on site the rep makes the foreman sign a disclaimer saying the Caltite representative was not there to supervise and Caltite is not responsible for workmanship.
 



Most specifiers think that the only way to get anything close to supervision is to buy a BBA certified water-resisting admixture.

But you shouldn't be fooled that you will get supervision, or by the bogus guarantees that come as well, just because a product has a BBA certificate.



We supply supervision and vibrating pokers that really work well for an extra cost. That way you know Supervision and good compaction will happen.

Please go the Basement Expert web site for details of the threaded fibreglass rods and nuts.





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