For bathroom tiling, balconies, pool surrounds, and stonemasonry where salt damp or calcium carbonate stains threaten the finish, Hydrophobic Additive provides permanent protection by treating the entire concrete mass. Added directly to the mix, this water-based liquid creates an invisible hydrophobic molecular structure within the pores of cement-based materials to lock out efflorescence without blocking vapour permeability.
Hydrophobic Additive acts as a bulk impregnating agent that repels liquid water while remaining breathable. By preventing the capillary action that draws moisture through concrete, brick, sandstone, and porous masonry, it stops waterborne salts from migrating to the surface. This mechanical control prevents picture framing in granite and basalt paving, stops salt attack in saline soils, and deprives moss and mould of the moisture required to grow on off-form concrete or brickwork. Unlike topical sealers, bulk impregnation protects the entire mass, meaning the water-repellent performance is unaffected by traffic wear, surface abrasion, or minor movement cracks.
Always use General Purpose Cement (Type GP) for applications where efflorescence is a risk. Do not use Builders Cement (Type GB); its high proportion of fly ash or blast furnace slag contributes to efflorescence and works against hydrophobic additives.
When mixing tile screed, sand from the building yard carries variable moisture that pre-dilutes the mix. To maintain correct dosage, add Hydrophobic Additive neat to the screed mixer at 100ml per 100L of mixer capacity, then add water to reach the desired consistency. For hand-mixed screeds, pre-gauge in a bucket with a tighter 1:80 or 1:50 dilution to compensate for wet sand.
Latex additives used in cement slurries or tile adhesives will delay the water-repellent performance of Hydrophobic Additive for approximately 6 days. While compatible, the system will not exhibit full hydrophobicity during this initial cure window. If rain enters tile adhesive notches before grouting, extract it with a vacuum and allow it to evaporate fully.
Supervisors should water-test all screeds, mortars, and concrete after 24 hours. A successful mix will show a distinct water-beading effect; if the substrate absorbs water, seek technical advice before proceeding.
Efflock can minimise saturation in stone bedding and grout, but suitability for natural stone requires on-site testing. Stone porosity and mineral composition vary significantly, and Efflock may cause visible dry spots if not applied uniformly or if the stone is pre-sealed.
Efflock provides an excellent additional barrier to a waterproofing system and can negate the need for a secondary membrane for efflorescence control. However, primary waterproofing membranes should still be installed according to relevant standards and manufacturers' instructions for water ingress prevention.
For most applications like tile adhesive, grout, render, and topping, prepare gauging water at a 1:100 ratio of Efflock to clean tap water. For tile screed, add neat Efflock at 100ml per 100L mixer capacity, then add water to achieve desired consistency, accounting for moisture already in the sand.
Efflock makes dark grouts hydrophobic to protect against secondary efflorescence. However, it does not assist with colour stability or prevent patchiness. Consider epoxy grout if colour consistency is a primary concern.
| Application | Key benefit | Primary trades |
|---|---|---|
| Tile screeds, adhesives, and grout | Controls water absorption throughout the system, preventing efflorescence, cryptoflorescence, and damp. Can eliminate the need for a secondary efflorescence membrane, saving cost. | Tilers, Waterproofers, Builders |
| Brickwork and stonemasonry mortar | Provides a hydrophobic damp-proof course, preventing rising damp and salt attack in saline soils. Repels dirt and inhibits moss growth for a cleaner appearance. | Masons, Bricklayers, Builders |
| Off-form concrete and concrete pavers | Bulk impregnation protects against chloride ingress and freeze/thaw damage. Repels dirt and suppresses moss growth, enhancing long-term durability and appearance. | Concreters, Paver manufacturers, Builders |
| Render and general cement-based materials | Offers invisible, bulk hydrophobic protection, dramatically reducing water absorption without filling pores. Improves curing and remains permeable to vapour. | Renderers, General Builders |
Use Type GP cement. For most mixes, prepare gauging water at 1:100 (Efflock:water). For dry screeds with variable sand moisture, dose Efflock neat per mixer capacity, then add water to achieve workability.
Measure additive neat based on mixer volume (e.g., 100 mL per 100 L). Mechanically mix to uniform dispersion.
Use 1:100 gauging water. Observe manufacturer water demand; Efflock may reduce water required slightly.
Compact screed thoroughly; wood-float to close. Achieve ≥90% adhesive coverage beneath tiles.
Damp cure 7 days; dry/stabilise ~2 weeks before tiling/membrane.
Protect from rain until joints are grouted and perimeter/expansion caulking completed.
Signal Word: Warning
Wear splash-proof goggles and PVC or rubber gloves. For large quantities or heavy contamination, use Viton® gloves and coveralls. If an inhalation risk exists, wear a Type A (Organic vapour) respirator.
Use in well-ventilated areas. Where an inhalation risk exists, mechanical extraction ventilation is recommended to avoid exposure.
Store in tightly sealed original containers in a cool, dry, well-ventilated area, away from incompatible substances, heat, and direct sunlight. Protect from temperatures below 0°C or above 45°C. Dispose of waste at an authorised chemical disposal facility.
Proper substrate preparation and integration of Efflock are critical to prevent efflorescence, damp, and salt attack in cement-based materials.
Surface prep: Concrete must be sufficiently cured and aged to mitigate shrinkage. Rectify any negative fall or ponding areas with a bonded screed before waterproofing. If exposed to atmospheric salt, thoroughly rinse the substrate.
Primer: Not required. Efflock is added directly to the mix.
Surface prep: Ensure concrete substrates are cured and clean. For timber frame and cement sheet structures, ensure construction provides fall. If bonding screed to concrete, use a traditional cement slurry. Protect from early drying and rain exposure for 24 hours post-application.
Primer: Not required. Mix Efflock into the gauging water or add neat to the screed mix.
Surface prep: Thoroughly rinse any substrate exposed to atmospheric salt. Clean any mortar smears or splashes mechanically before using acid for cleaning. Protect mortar from rain prior to initial set and for 12-24 hours after. Fill core holes in bricks flush with mortar.
Primer: Not required. Mix Efflock into the mortar mix.
| Property | Value |
|---|---|
| Appearance | White Liquid |
| Odour | Slight Odour |
| Flammability | Class C2 Combustible |
| Flash Point | > 96°C |
| Boiling Point | 100°C |
| pH | 8 (Approximately) |
| Solubility in Water | Soluble |
| VOC Content | VOC Free |
| Dilution Ratio (General) | 1:100 (Efflock:Water) |
| Dilution Ratio (Screed) | 100ml (neat) per 100L mixer capacity |
| Application Temperature Range | 4°C to 35°C |
| Minimum Cure Before Rain Exposure | 12-24 hours |
| Shelf Life | At least 24 months (in original sealed containers) |
| Storage Temperature Range | Above 0°C, below 45°C |
Here are some common examples on where Efflock Hydrophobic Additive used by our customers.
