waterproof concrete

BASF Masterlife 799 explained.

I used this for 2 years before I discovered PCE plasticiser from SE Asia, which I found much better as well as much cheaper. My positive feedback helped them earn their BBA certificate.

I found it powerful enough though it retarded the concrete set, which I did not like.
Retarding a set can increase grout loss lower down a deep wall form.

The BBA certificate approves this product for basement construction despite demonstrating no useful improvement in water resistance.

Contrary to the BBA certificate, in my opinion this product makes the same concrete mix, basically C35A, waterproof, because I always used the same mix and it made it just as workable.

I never asked BASF for their guarantee or warranty. However I recall one producer who stocked it, but I bought his concrete without it, telling me that 4 pages of disclaimer were to be sent to customers before it should be supplied to them.

It would be entirely reasonable for any disclaimer to point out that visible leaks are through dirt, voids and cracks caused by poor workmanship and not through the sound concrete. Perhaps BASF also recommend supervision?

The BASF BBA Certificate.

My comments









The certificate states that the product is a blend. We still have some, but with a magnifying glass it seems to us to be a single material.

It does not contain PC.








This must be concrete containing flyash. Pure OPC could not have a 130mm slump with 0.50 water.

It seems to preserve the slump long enough to deliver and discharge.



This is a small improvement. We think it would have been better with pure OPC.

These BBA figures are non-sensical.
26% by mass of the control concrete represents 600kgs, or 600 litres which is 60% of a m³.
see my notes below

Really? Despite 10% less water? Then they used a very permeable control mix. Did they forget sand?

Again, no difference, surely wrong.



only 'can be obtained'




We used only pure OPC with the BASF 799 product and it retarded the initial set, though the OPC initial set time is barely 120 minutes in most weathers.

This must be a flyash mixture.







This clause seems to exclude the BASF from the equation.
These quotes in dark red are all from the BASF product certificate on the BBA web site here.

But we have changed the order in which they appear.


This Agrément Certificate Product Sheet relates to BASF MasterLife WP 799 Watertight Concrete Powder, a water-resisting and superplasticising admixture powder for use in concrete mixes to provide watertight concrete suitable for basements, roofs, swimming pools, tunnels, and culverts, without the requirement for additional applied protection.

This certificate ... has to be read, considered and used as a whole document - it may be misleading and will be incomplete to be selective

1 Description
BASF MasterLife WP 799 Watertight Concrete Powder is a combined water-resisting and superplasticising admixture, for incorporation into concrete mixes to enhance the water resistance and durability properties of the hardened concrete.

3.4 The product is not deemed to be 'hazardous'

4.1 The product is satisfactory for use in concrete mixes at an addition rate of 1.75 kg/m³ of concrete to provide watertight concrete for basements, roofs, swimming pools, tunnels and culverts, without the requirement for additional applied protection.

From Table 1 Effects of the product on the properties of fresh wet concrete(1)
Property Control concrete BASF MasterLife WP 799
(1.75 kg/m-3)
Water / cement ratio 0.50 0.45
Slump (mm)
0 minimum 130 150
30 minimum 85 135

(1) The specific effect of the product on these properties for a particular mix and site conditions should be evaluated through site trials prior to use.

6 Water penetration and absorption
6.2 Tests conducted on a concrete containing the product at an addition rate of 1.75 kg/m-3 showed a water permeability(1) of 2.75x10–13 m/s-1 compared to 3.84x10–13 m/s–1 for the control concrete.

6.3 Tests conducted on a concrete containing the product at an addition rate of 1.75 kg/m-3 showed a capillary absorption(1) of 26% by mass of the control concrete at 7 days and 29% by mass of control at 90 days.
(1) The specific effect of the product on these properties for a particular mix and site conditions should be evaluated through site trials prior to use.

7.1 Concrete containing the product has a similar permeability to water vapour as that of an equivalent plain concrete.

7.2 Tests on concrete containing the product at an addition rate of 1.75 kg/m-3 showed a water vapour permeability(1) of 744 x 10–12 g/m (Ns)–1 compared to 730 x 10–12 g/m (Ns)–1 for the control concrete.

7.3 Concrete made with a high water/cement ratio can have a water vapour permeability greater than 3000 by 10–12 g/m (Ns)–1. The permeability of concrete is strongly dependent on the exact mix design and the figures given in Section 7.2 indicate the levels that can be obtained using the product.

From Table 4 Effects of the product on the setting properties of fresh wet concrete(1)
Property Control concrete BASF MasterLife WP 799
(1.75 kg/m-3)
Water / cement ratio 0.50 0.45
Setting time (minute)
initial set 210 195
final set 300 280

(1) The specific effect of the product on these properties for a particular mix and site conditions should be evaluated through site trials prior to use.

19.5
For Grade 3 (where control of water vapour is required), it will be necessary to provide a mix with a sufficiently low vapour permeability in combination with an adequate section thickness (see sections 7.2 and 7.3).

20.2 The concrete must have a minimum cement content of 350 kg/m–3, be batched with a maximum water/cement ratio of 0.45 and have a minimum consistence of S3.



What did BBA do with this very useful chemical to "prove" that it barely makes any difference to cement-rich, reduced water concrete?

It does make a difference. We built or helped build 10 domestic basements with this product in the concrete and the outcomes are, we are sure, far better than this certificate would lead anyone to believe.

The only explanation we can come up with for the poor results are poor concrete. For instance, some authorities believe that flyash in concrete is relatively unreactive and where the flyash is several grains deep between grains of cement no cement gel gets through to form crystals between the flyash. If this is correct, then maybe the BASF results are poor only because the ways through between flyash grains remain.



See the chart below.

BBA certificates have figures for water permeability.

The Concrete Society had the idea of plotting them all on a chart. I have done that as well. But I have also included some best guesses. For instance, only the Caltite certificate has no figures for compressive strength.

Some of the control concretes were better than concretes with admixture in them. BASF's control concrete was better than Caltite and Sika but even with 799 worse than the control concretes used for Fosroc, Krystol or Pudlo.

The BASF MasterLife used to be called Rheofit.

It seems very unlikely to me that wisely conducted experiments would show such a massive increase in compressive strength and yet almost no improvement in water penetration.


waterproof concrete



In comparison, we get concrete delivered to every project tested for permeability.

waterproof concrete