LEAK-FREE WATERPROOFING. ALWAYS!
Crystalline waterproofing for below-ground applications and water tanks.
Based on more than 42 years old proven crystalline waterproofing technology, CWS Admix greatly improves on the initial concept of crystalline growth, and protects concrete structures, essentially doubling their service life.
CWS Admix forms crystals within the pores and capillaries in the concrete, effectively blocking the passage of water. It also seals cracks in the concrete up to 0.4mm (1/64″) and will seal future hairline cracks in the presence of moisture.
The application of CWS Admix
As and Admixture in Fresh Concrete
CWS Admix is a concentrate and is very simply – and easily – administered at the batch plant, within the dry mix, or added to the concrete truck on site.
As a Slurry on New Projects and Repairs
Mixed with silica sand and cement at specific proportions, CWS Admix forms a slurry that can be trowelled on concrete surfaces, be it on new projects or for the repair of leaking structures, e.g. basements, lift pits, rising humidity through foundations slabs etc.
Fixed Dosage
Traditional crystalline waterproofing admixtures are dosed in the concrete as a percentage of the binder, and the quantity is increased when the cement content increases.
When variations are made to the design mix, the quantity of waterproofing admixture per cubic meter also needs to change. In case this is forgotten, the result will be incorrect dosing, and leakages will occur.
CWS Admix is added at a fixed dosage per cubic meter of only 0.8 kg/m3, regardless of the cement content in the mix. This results in:
- Simple and rapid calculation of the appropriate quantity for any concrete mix
- Protection against human error
- Safety from knowing that any alteration in mix design needs no recalculation of the amount of admixture required
- Peace of mind that the project is safe and correctly waterproofed
The fixed dosage of CWS Admix is a reason for Consultants and Contractors to adopt the product
CWS Admix versus other Crystalline products
CWS Admix: Dosed at 0.8 kg/m³ per cubic metre of concrete). Regardless of cement content.
Other crystalline: Variable dosage. Calculation must be made for every pour. These calculations are based on dosing charts, which are not easy to use, leave room to misinterpretation, that leads to incorrect dosages, confusion and accordingly: leaks in the project. A very expensive mistake, that costs money, time and damaged reputation.
The below example of variable dosage chart of another crystalline admixture, compared with CWS Admix, clearly illustrates the issue.
Ask yourself: Which solution makes you feel safer?
Concrete Protection
Not only is CWS Admix ideal for waterproofing residential and commercial properties, but it is also perfect for the protection of concrete in areas where it is subjected to harsh conditions that cause degradation e.g. from salinity on marine projects, from harmful contaminants e.g. in wastewater treatment plants, water collection systems etc. By blocking the ingress of water-borne chlorides and other chemicals, CWS Admix protects the steel rebar against corrosion, greatly extending the service life of civil engineering projects.
Super-fast Application
Project construction is the definition of “working on a ticking clock”. Whatever project time saving can be secured, is valuable. CWS Admix is added to the concrete on the day of production. As soon as the formwork is removed, the structure is already waterproofed. No delays waiting for the right timing to place waterproofing membranes and coatings, and no requirement to delay backfilling the area, until the application of external membranes around the basements is accomplished, a task often deferred for many weeks, because of harsh weather conditions.
Hydrostatic Pressure
CWS Admix is an excellent fit for situations where the presence of hydrostatic pressure and continuous ponding is expected. It has been tested several times and proven to meet the EN12390-8 European standard, which stipulates the product to perform under 5 bars of pressure.
Additionally, CWS Admix has successfully passed laboratory testing under 1.4MPa, or 14 bars of hydrostatic pressure (140m of waterhead)
Refer to CWS for more details.
A Projects’ Product
CWS Admix is exclusively applied by Approved Applicators, who have been trained in its application both as an admixture and as a trowelled slurry. Rather than allow DIY amateur use, Concrete Waterproofing Systems Ltd. organizes full application training and annual re-approval to all trained technical teams worldwide, to ensure proper quality control and customer service, that have made CWS a top-safety choice, for consultants and contractors around the world.
We are not just offering you a product, we are ensuring you a result: a LEAK FREE PROJECT. Every time!
Environmentally Friendly – Earn LEED Points
Ever since its inception, CWS Admix was designed with observation to the protection and preservation of ecosystems around the projects it is used on. CWS is a proud member of the world renowned US Green Building Council (USGBC), responsible for the LEED Accreditation Program.
- Non toxic
- Suitable for use with potable water (NSF/ANSI/CAN 61-2020 approved)
- Does not create landfill like membranes
- No VOCs
- Helps you earn LEED points on suitable projects
The mechanism of CWS Admix
CWS Admix reacts with cement hydration products (e.g. with calcium hydroxide) and precipitates insoluble crystalline phases. These crystals fill capillary pores and micro-cracks, reducing porosity and increasing impermeability. This barrier of insoluble crystals constitutes a permanent barrier to the ingress of water e.g. due to humidity, leakage, new cracking), while at the same time air and vapor are allowed to circulate, helping the concrete breathe, without trapping moisture on the inside.
The mechanism is described as both immediate and delayed/self-healing: some crystals (e.g. various calcium silicates, carbonates, stable hydrate phases) form during setting/hardening, sealing early porosity and micro-cracks; unreacted admixture remains dormant and reactivates when new cracks or moisture ingress occurs — producing further crystals that fill and seal additional cracks, physically blocking pathways for water.
The pace at which the crystal growth develops in the concrete has been widely researched and varies according to several parameters that affect the mix, the curing regime and the proprietary compositions of various admixtures. CWS Admix is one of the fastest crystalline admixtures in the market and its waterproofing properties are normally achieved 7-10 days from pouring, however improvements in it performance have been observed over subsequent weeks.
Important to Know About CWS Admix
- CWS Admix is compatible with most of the known admixtures, commonly used in concrete
- Like all crystalline products, CWS Admix displays a light plasticizing and retarding effect in the concrete, favoring conditions where the batch plant is not very near the site, an issue raising concerns about its consistency upon arrival. Because of this effect, the removal of retarders and the adjustment of plasticizers should be considered
- A trial mix is always considered necessary for the above reasons
- It has little or no effect on the compressive strength of concrete
- CWS Admix has exhaustively been tested and found to comply with EN12390-8 standard, acknowledged to prove watertightness, under 5 bars of pressure within 72h
Please contact CWS for further information, or to discuss your specific project
BENEFITS
- Leak-free waterproofing
- 25-year warranty
- Fixed dosage. No need to adjust for cement content
- Seals static cracks up to 0.4mm
- Seals future cracks
- Helps earn LEED points
- Resists hydrostatic pressure
- Approved under EN:12390-8
- Environmentally friendly
- Safe with drinking water
- Very cost-effective!
MORE DETAILS
See datasheet for details of application and technical considerations.TYPICAL APPLICATIONS
- Basements and Slabs
- Below ground car parks
- Elevators pits & foundations
- Sewage plants
- Water treatment works
- Tunnels and Canals
- Foundation walls & footings
- Concrete Pipes and Pre-Cast
- Core filled blockwork
- Water Tanks & Reservoirs
CWS Admix® Frequently Asked Questions (FAQ's)
CWS Admix™ waterproofing capability will last for the life of the structure. It is a concentrate, consisting entirely of active ingredients which continuously reactivate, meaning they will continue to work for the life of the structure.
Generally, all crystalline products, including CWS Admix™, cause some retardation of the set. For this reason, we recommend that consideration be given to the removal of water reducing Admixtures or, alternatively, the use of an accelerator when using CWS Admix™.
Yes. Although CWS Admix™ is not actually a plasticiser, it does have some plasticising effect on the concrete. Therefore, consideration should be given to removing other plasticisers when using CWS Admix™.
Yes, DEFINITELY. We strongly recommend that a trial mix be carried out prior to placement, so that all parties are fully aware of the mix properties, prior to final concrete placement.
Ideally CWS Admix™ should be added at the batch plant. However, it can be added directly into the concrete truck. If added to the concrete truck after the addition of water, ensure that the mix is turned for a minimum of ten minutes after the addition of water.
Yes. CWS Admix™ resists both positive and negative hydrostatic pressure. It meets the European standard EN 12390-8, which measures permeability and depth of penetration under 5 bars of hydrostatic pressure for 72h.
CWS Admix™ protects concrete from damage caused by most chemicals. As a general guide, chemicals that are in a PH range between about 2.0 and 12.0 are unlikely to affect CWS Admix™ treated concrete. However, for details regarding specific chemicals, please contact your local distributor.
Yes. By preventing the ingress of water, CWS Admix™ protects both the concrete and the reinforcement from deterioration, arresting the diffusion of chlorides and sulfates.
Yes, absolutely. Unlike membranes, which deteriorate and create enormous amounts of landfill, CWS Admix™ remains an integral part of the concrete forever. It contains no Volatile Organic Compounds (VOC’s) and is completely non-hazardous.
Yes. CWS Admix™ has been tested and approved for use with potable water.
Yes, CWS Admix™ is compatible with most Admixtures. However, like all crystalline products, CWS Admix™ Concentrate can have a plasticising effect and may cause an extension of set times. The amount of extended set will be affected by mix design, climatic conditions etc.
Whilst CWS Admix™ Concentrate can be used in conjunction with most Admixtures, consideration should be given to the reduction or removal of Admixtures that retard, such as plasticisers, water reducing Admixtures etc.
Whilst generally there is no adverse effect on CWS Admix™, from common Admixtures used in concrete, as there are thousands of such products around the world, a trial mix is recommended when using CWS Admix™ Concentrate in addition to other Admixtures.
Yes. Firstly, mix CWS Admix™ concentrate with silica sand and portland cement, according to the datasheet, before applying it as a slurry to a concrete surface.
CWS Admix™ is suitable for all types of concrete surfaces, including poured in place, pre-cast, or block concrete. It is not suitable for non-concrete building materials.
Yes. Because CWS Admix™ prevents the ingress of water, it protects the concrete against the effects of freeze and thaw.
CWS Admix™ is traditionally used on below grade structures, such as basements, as well as reservoirs, tunnels, foundations, underground vaults, water tanks, sewage and water treatment tanks, storm water collection, car parks, swimming pools and foundations. It is also suitable for use on pre-stressed decks.
The environmentally sustainable, crystal growth technology of CWS Admix™, brings significant efficiencies and differences to the capability of concrete waterproofing. This technology ensures CWS Admix™ has greater capability than traditional membranes and cementitious coatings.
The developing crystalline structure integrates with the entire concrete matrix, to ensure water penetration and chemical ingress are stopped.
CWS Admix™ reacts with the hydration products of cement, to form crystals within the cracks, pores, and capillaries of concrete structures, effectively blocking the passage of water, to provide a 100% watertight seal for the structure.
After the crystalline process has successfully waterproofed the structure, the active chemicals in CWS Admix™ remain dormant in the concrete. Subsequent contact with water will reactivate the regenerative crystal growth technology.
CWS Admix™ is completely resistant to hydrostatic pressure, as it has no dependency on surface adhesion for its complete waterproofing capability.
CWS Admix™ is not subject to any form of deterioration. CWS Admix™ is integrated into the very structure of the concrete. It is a permanent component which continuously reacts in the presence of water, thereby, providing lifetime protection to any concrete structure.
The crystalline growth technology of CWS Admix™ provides many advantages over traditional membranes:
- Does not require costly surface preparation
- Does not deteriorate, puncture, tear, or come apart at the seams.
- Does not need any protection during back filling, or during placement of steel, wire mesh, and other materials.
- Waterproofs on both the positive and negative side of a structure.
- Does not need any form of sealing, overlapping and finishing of seams, at corners or edges.
- Does not need reapplication, nor future maintenance, as it remains active for the life of the structure.
- Does not emit VOC’s.
- CWS Admix™ is less costly and more environmentally friendly, as it never needs replacing!
The general dosage as an Admixture is 0.8kg per cubic metre of concrete. Under special circumstances, it may be necessary to vary this amount according to site conditions or design mix requirements.
CWS Admix™ is best added to the dry mix at the time of batching. However, it can be added to the mixer on site. When added directly to the concrete truck, it is essential to rotate the mix for ten minutes prior to pouring.
CWS Admix™ has been tested several times for its effect on the compressive strength of concrete. Test results vary according to particular concrete compositions that range, from nil effect, through to a slight increase of compressive strength. The temperature of the concrete is not affected.
The performance of concrete begins to lose strength at 300oC irrespective of any surface treatment.
CWS Admix Typical Applications
The CWS Admix features crystalline waterproofing for below ground and water tank applications including:
- Basements
- Below ground parking structures
- Elevator pits & foundations
- Sewage & water treatment works
- Canals
- Reservoirs
- Swimming pools
- Tunnels
- Core filled blockwork
- Foundation walls
- Slabs
- Footings
- Concrete pipes
- Pre-cast
- Rooftops and podiums, where appropriate
- Water tanks
Click photo to enlarge:
