Chryso Eastern Africa is supplying a vital admixture for the concrete mix used for the construction of Nova Apartments, a new R180 million luxury apartment block in Nairobi, by the main contractor, Aggregate Construction.
Trevor Sawyer, Country Manager for Chryso Eastern Africa, says waterproofing products from a.b.e. Construction Chemicals – part of the Chryso SA Group – will also be used for the construction of the new landmark building in Muthangari Drive in Westlands, Nairobi.

Sawyer says the Chryso Group products selected for use on the new prestige Elmridge Developments project are:
* CHRYSO Fluid L – a high range water-reducing, super-plasticising admixture;
* a.b.e. duraflex – a cementitious flexible waterproofing slurry; and
* a.b.e. ecofelt – a polypropylene saturation membrane, used to reinforce the a.b.e. duraflex waterproofing.
Chryso Eastern Africa is supplying a total of about 60 000 litres of CHRYSO Fluid L admixture to Aggregate Construction for the concrete required to build the multi-storey apartment block, scheduled for completion in October next year. Sawyer and Aggregate Construction’s Paresh Hirani worked in close collaboration to optimise the content and performance of the concrete mix for the project which was started in August last year. Sawyer was on site right from the first cast and Chryso Eastern Africa also supplied the main contractor with a Chryso dosing system to ensure consistency in the concrete mix.

CHRYSO Fluid L offers several benefits to a concrete mix. Included are:
* Substantially reducing the water content without negatively affecting the mix’s consistency; and
* Significantly increasing the slump/flow of the concrete mix and its workability.
CHRYSO Fluid L is compatible with all types of cement on the Kenyan market, including the main stream Pozzolanic cements.
The technical representative who is assisting Mau West Ltd for the waterproofing part of the project is Geoff Dagger, a.b.e. Technical Sales Representative at Chryso Eastern Africa.
For the waterproofing of the swimming pool, podium, balconies and bathrooms, a.b.e. duraflex with ecofelt reinforcement to cover a total area of about 5500m2 will be supplied to the specialist waterproofing contractors, Mau West Ltd. Both the main contractor and specialist waterproofers are leading Nairobi-based companies.

Dagger says a.b.e.’s duraflex is a ready-to-use flexible slurry based on a special synthetic resin dispersion and a blend of selected cements, mixed with carefully selected graded aggregates. duraflex is non-toxic, self-curing, and effective on both the negative or positive side (positive side waterproofing applies to sides with direct exposure to water, while negative side waterproofing applies to the opposite or interior side from which water occurs.) The product has high bonding strength, and offers strong resistance to abrasion as well as chloride ion penetration.

Dagger says the ecofelt reinforcement will maximise duraflex’s performance because ecofelt has internationally proved to be one of the best saturation membranes in waterproofing. “ecofelt has a highly porous fibre structure, manufactured by needle-punching the fibres to form a uniformly structured sheet,” he explained.
The architects for Nova Apartments are Beglin Woods Architects Kenya, which have already won an Architectural Association of Kenya (AAK) “Best Concept” award for the luxury residential apartments and penthouses of the spectacular new development. The Beglin Woods acclaimed design for the 17 storey Nova Apartments include an indoor/outdoor swimming pool, spa, gym, cinema, convenience store and expansive open grassed area with water features and jogging track.

Work in progress on the construction of Nova Apartments in Nairobi for which the Chryso Group supplied several products.


Chryso Southern Africa has launched a new range of dust suppressants locally developed by the company specifically for the sealing of dirt roads on the African continent.

The new Chryso Eco Dust range consists of four products:
• Chryso Eco Dust 100: an emulsified road surface lubricant with particles that bind together to form a dust-suppressing film. This ‘top of the range’ poly-adhesive surface sealer, with ultra-fine dust-binding particles, offers exceptionally long water resistance;
• Chryso Eco Dust 200: a vinyl acetate emulsion surface sealer that can be used on its own on non-maintained roads or, for longer service on maintained roads, as a second application following pre-sealing with Chryso Eco Dust Primer;
• Chryso Eco Dust Oil: an emulsified surface lubricant ideal for users with a regular maintenance programme; and
• Chryso Dust Primer: a light brown surface primer, ideally used in conjunction with Chryso Eco Dust 200.

Michelle Fick, Chryso Southern Africa Group Executive Relationship and Project Manager, says the new Eco Dust range will ideally complement and expand the wide range of dosing products and equipment already supplied by the company locally.

“The eco-friendly, UV-resistant and VOC-free Eco Dust range will be particularly welcomed by mines and quarries that have to comply with increasingly stringent health, safety, and environmental regulations all over Africa. Because of the long-lasting effect of the Eco Dust range, the fuel consumption and carbon dioxide emissions of water tankers spraying the dirt roads will be drastically lowered. It is easy to apply, in prescribed diluted form, with any water tanker fitted with a rear-mounted liquid distribution bar, and the roads can be used immediately after being sealed,” Fick states.

The sealing process, basically, consists of applying the slurry evenly over the road surface followed by compaction with a vibratory roller. The road is then swept with a mechanical broom, and compacted again without vibration.

Fick says reductions in water consumption, road-grading labour, as well as vehicle maintenance are additional benefits. Increased visibility and road gripping for all vehicles adds to the Eco Dust safety advantages.

“The new range’s applications are extremely varied as well. Apart from mines and quarries, dusty gravel and dirt roads that require sealing and maintenance can be found at cement plants, precast yards, building sites, farms, game reserves, rural airfields, paddocks, and less developed residential areas. Country sandy football pitches could also do with regular sealing. Agricultural co-ops and dust-sensitive sections of the forestry industry are other potential applicators.

“The Chryso Eco Dust range created tremendous interest when it was recently launched at The Concrete Conference in Johannesburg. Its low cost of application and reduced maintenance costs compared to paving or tarred roads are seen as major benefits at a time when many industries, especially mining and agriculture, are experiencing difficult times,” Fick adds.

Chryso Eco Dust is easy to apply to road surfaces with a water tanker fitted with a liquid distribution bar.


The recent Knysna wildfires and building fires in Johannesburg, as well as mine fires underground, are a reminder of the value of specialised construction materials in passive fire protection, especially in reducing explosive spalling.

Such a solution is the specially designed Adfil IGNIS® monofilament polypropylene fibres, distributed locally by CHRYSO Southern Africa, leading supplier of concrete and cement admixtures and ancillary products. Developed by Adfil Construction Fibres, a division of the UK-based Low & Bonar Group, the IGNIS fibres have been used in concrete mixes to enhance the fire rating of concrete structures and have been successfully applied in tunnels, sprayed linings, precast segments and pumped concrete behind slip-formed shuttering.

In a move that will bring this innovated technology closer to home, Adfil recently appointed CHRYSO Southern Africa as its partner to grow its fibre business into Africa. There will also be collaboration between Adfil and specialist South African company Oxyfibre, which has developed patented surface technologies and nano-technologies for polypropylene fibres; it has also treated and supplied fibres to CHRYSO Southern Africa for almost two decades.

According to Izak Louw, operations manager at Oxyfibre, fire can cause explosive spalling in concrete structures when ‘free water’ in the concrete pores – water that has not been consumed during the hydration reaction and remains unused in the concrete – becomes steam when exposed to fire and causes explosions that break up the concrete.

“Falling concrete then presents a serious safety risk, and the integrity of the concrete structure is also compromised,” says Louw.

To enhance the fire rating of concrete structures and reduce the risk of spalling, Adfil’s polypropylene fibres are added to the concrete mix for the purpose of increasing permeability during heating, thus reducing pore pressures.

“In the case of fire, the fibres will start to melt when the heat of the concrete is approximately 160°C,” he says. “When the temperature reaches 360°C, the fibres will disintegrate to provide millions of capillaries in the concrete for the moisture to escape. The result of using these fibres in concrete is that there is no build-up of pressure and hence no explosive spalling.”

According to Louw, there is substantial scope in South Africa and in Africa more broadly for the use of specialised fibres in concrete as passive fire protection, as it can prevent the catastrophic failure of concrete structures – from mine tunnels to high-rise buildings.

“Furthermore, polypropylene fibres offer a three-dimensional system, which helps to prevent shrinkage cracks from occurring,” he says. “The fibres increase the tensile strain capacity of the mix at the plastic stage, while crack control reinforcement would merely hold the cracks together once the concrete has failed.”

Proven at such test facilities as TNO in Holland and the BRE in England, Adfil IGNIS® has been used in many road tunnels, primarily to avoid the potential collapse of these structures in the event of serious fires.