HYPOLSEAL Cementitious Crystallizing Concrete Waterproofer

HYPOLSEAL Cementitious Crystallizing Concrete Waterproofer


HYPOLSEAL is a cementitious, crystallizing concrete waterproofer, the inorganic chemicals of which penetrate into the substrate by diffusion and react with the free lime in the concrete forming insoluble crystals, sealing all paths of water penetration.


HYPOLSEAL is suitable for the waterproofing of concrete in most situations, including:-Retaining Walls, Basements & Floor Slabs. Reservoirs, Water Tanks & Sewerage Plants. Lift Pits, Sumps & Planter Boxes.

Bridge Decks & Viaducts


The use of HYPOLSEAL is not detrimental to the compressive, tensile or flexural strengths of the concrete to which it is applied.

Full details including test reports are included in the Technical Manual.


  • Penetrates to seal existing and new cracks of up to 300 microns.
  • Can be applied to either the active or passive side.
  • Effective on moist surfaces. Protection not required.
  • Non-toxic and can be used in contact with potable water.
  • Requires minimal surface preparation. Protects reinforcement by preventing the intrusion of moisture, salts, chemicals and other harmful fluids.
  • Allows the concrete to breath. Cannot be torn or perforated. Improves chemical resistance.
  • Ease of application.
  • Once the crystals have formed, they remain permanently and further contact with water will reactivate the process of sealing.
  • HYPOLSEAL reacts with the free lime and moisture in concrete forming insoluble crystal complexes in the capillary tracts and fine shrinkage cracks within the structure.

This unique characteristic provides long term protection and eliminates maintenance problems. Any fine shrinkage or settlement cracks which subsequently occur are sealed by the chemical reaction between the diffused HYPOLSEAL chemicals and the alkaline constituents within the concrete.


All surfaces should be washed with a high pressure water jet at a pressure of at least 100 bar to ensure through scouring and pre-wetting of the concrete. By removing all scale, form oil, grease, laitance etc. an open capillary system is produced, allowing the HYPOLSEAL chemical process to take place. Precast concrete requires at least 200 bar.

HYPOLSEAL should not be applied to an extremely smooth surface.


HYPOLSEAL SUPER and HYPOLSEAL FINISH are mixed with clean water at the rate of 10-12 litres per 25kg bag, using a slow speed electric mixer, ensuring that the slurry is free of lumps.


HYPOLSEAL is applied by special brush or spray equipment to thoroughly cleaned and saturated concrete surfaces, at the rates shown below:

Floor Slabs & Construction Joints

Super 1.0 kg/m² in one application


Super 0.75 kg/m² in one application

Structures with render

Finish 1.0 kg/m² in one application

When HYPOLSEAL FINISH is applied onto HYPOLSEAL SUPER, the application must take place shortly after initial set, to ensure a sufficient bond to the smooth surface of the HYPOLSEAL SUPER.

HYPOLSEAL should not be applied if the temperature is likely to fall below 5OC during or within 24 hours of application.

Application to lean concrete should allow sufficient time for the HYPOLSEAL SUPER to achieve initial set before placing the concrete.

Oil based formwork release agents are not to be used as this will affect the bonding of HYPOLSEAL to the concrete.


HYPOLSEAL allows concrete to breath and thus the transmission of water vapour. Therefore vinyl tiles, parquet flooring or oil based coatings must NOT be used in conjunction with HYPOLSEAL.

Where marble or granite are to be used, the unpolished surfaces should be treated with ACRISEAL acrylic sealer.


Surfaces treated with HYPOLSEAL and left exposed are to be kept damp for at least 3 days after application. This can be achieved by periodically spraying with or by covering the surface with polythene sheets, wet sand or gunny sacks. Backfilling with moist soil may commence 36 hours after application.

Surfaces treated with HYPOLSEAL to be painted should be neutralised with a 1:8 hydrochloric acid (or similar) and water solution and thoroughly rinsed off with water, before the application of the HYPOLSEAL.




Concretes of various grades were tested and treated with HYPOLSEAL up to a water pressure of 7bar. On the weaker grades up to 141cc of water penetrated into the control concrete but the treated remained unaffected in every case.

In another test, 100mm dia sand/cement mortar discs were produced and cured for 60 days prior to testing. A 2m column of water was introduced on the top of the discs and this pressure was maintained for 29 hours. The quantity of water percolating from 24th to the 29th hour and recorded in gm/hr. The untreated discs averaged 56.1gm/hr and the treated discs 01.gm/hr.


HYPOLSEAL has no detrimental effect on the existing strengths of concrete onto which it applied.


HYPOLSEAL SUPER & HYPOLSEAL FINISH are packed in 25kg heat-sealed plastic bags with a plastic inner liner.


As with all cementitious products, HYPOLSEAL has high alkali content and therefore skin protection is recommended. HYPOLSEAL should be washed off immediately with clean water and rubber gloves should be worn. Refer to Safety Data Sheet for more details.