STP ShaliKote SWP
A clear, penetrating silane/siloxane impregnation that makes concrete, brick and masonry facades water-repellent without changing their appearance.
What is it?
A solvent-based, colourless silane/siloxane water repellent (Silicon Water Peller) that soaks into porous surfaces rather than sitting on top like a film coating.
Where is it used?
Exposed concrete, fair-face brickwork, stone and masonry facades, plaster, parapets and other above-grade vertical surfaces that need to breathe but repel driving rain.
Why use it?
It reduces water absorption and the chloride and pollutant ingress that ride in with it, while leaving the surface open to water-vapour diffusion and visually unchanged.
How is it applied?
Flood-applied by low-pressure spray, brush or roller onto a clean, dry substrate in two wet-on-wet passes, letting it penetrate rather than build a surface layer.
About STP ShaliKote SWP
STP ShaliKote SWP is a clear, solvent-carried silane/siloxane treatment engineered to make mineral building surfaces water-repellent from the inside out. The name SWP stands for Silicon Water Peller, and that captures exactly how it behaves: the reactive silicon molecules are small enough to travel deep into the capillary pore network of concrete, brick and stone, where they chemically bond to the substrate and line the pores with a hydrophobic skin. Water beads and runs off, but the pores themselves stay open, so trapped moisture and water vapour can still escape. This is fundamentally different from a bituminous coating or an acrylic paint that forms a film on the surface and can blister or peel once water gets behind it.
For engineers and consultants working on facades, the appeal is that ShaliKote SWP protects without being seen. There is no colour change, no gloss and no film to weather, so heritage brickwork, architectural concrete and fair-faced masonry keep their natural look while shedding driving rain, cutting down on damp patches, efflorescence and the freeze-thaw and pollutant damage that follow water penetration. Because it is a penetrating impregnation and not a decorative membrane, it is best understood as a durability and water-management treatment for above-grade surfaces rather than a tanking or below-grade waterproofing system. Space Arc Engineering supplies it as an authorised STP distributor across Delhi NCR and pan-India, with application guidance for site teams.
The technical insight
The chemistry hinges on hydrolysis and condensation. Silanes are very small, highly reactive molecules that penetrate deep but are volatile; siloxanes are larger oligomers that react faster and stay nearer the surface. A blended silane/siloxane system such as ShaliKote SWP gets the best of both: the silane fraction drives depth of penetration while the siloxane fraction anchors the treatment in the outer zone. Once inside the pore, atmospheric and pore moisture hydrolyse the reactive groups, which then condense onto the silica-rich substrate and to each other, forming a permanently bound polysiloxane resin that presents outward-facing hydrophobic alkyl groups. The result is a lining of water-hating molecules along the pore walls that stops liquid water from wicking in by capillary action, yet leaves the pore itself physically open. That open pore is the whole point: vapour can still diffuse out, so the wall dries rather than staying saturated behind a sealed skin. Because the active substance is bound within the substrate and not exposed as a surface film, it is not abraded away by rain or degraded by UV the way a topcoat would be, giving a long, maintenance-light service life.
Where it is used
- Water-repellent impregnation of exposed reinforced-concrete facades and soffits
- Protection of fair-face and exposed brickwork against driving rain and rising damp
- Treatment of natural stone and masonry on heritage and architectural buildings
- Sealing of external plaster and render to reduce water uptake and efflorescence
- Parapet walls, copings and boundary walls exposed to weathering
- Precast concrete panels and cladding where a clear, invisible protection is required
- Priming and reducing water absorption on substrates ahead of decorative overcoating
- Reducing chloride and airborne-pollutant ingress on structures in coastal or urban environments
Key advantages
- Colourless and invisible after curing, so the natural surface appearance is preserved
- Penetrates and bonds within the substrate rather than forming a peelable surface film
- Keeps the surface breathable, letting water vapour escape while repelling liquid water
- Cuts water, chloride and pollutant ingress, slowing corrosion and freeze-thaw damage
- Reduces damp patches, efflorescence and biological growth linked to a saturated wall
- Solvent carrier aids deep penetration into dense and low-porosity concrete
- Ready to use with no on-site mixing, applied by simple spray, brush or roller
- Low-maintenance protection that is not worn away by rain or degraded by UV like a topcoat
Limitations & considerations
- It is a water repellent, not a waterproof membrane; it will not bridge cracks or resist standing water or hydrostatic pressure
- Not suitable for below-grade tanking, water-retaining structures or basements where a bituminous or crystalline system is required
- Effective only on sound, absorbent mineral surfaces; it does little on glazed, painted or non-porous substrates
- The substrate must be clean and dry at application, and rain-free curing time is needed, so it is weather-dependent
- Being solvent-based, it needs adequate ventilation, fire precautions and PPE, and is unsuitable for potable-water contact surfaces
- Cracks, defective joints and structural leaks must be repaired separately beforehand, as impregnation alone will not stop them
Selection & best practice
Success with ShaliKote SWP is mostly about substrate preparation and generous, penetrating application. The surface must be structurally sound, clean and dry: remove dust, laitance, loose material, oil, old coatings and any algae or fungal growth, and let the wall dry out fully after cleaning, since surface moisture blocks penetration. Repair cracks, spalls and open joints with the appropriate repair mortar first, because the impregnation seals pores, not defects. Apply in dry weather with no rain forecast during the curing window, flooding the surface from the bottom up in two wet-on-wet coats so the second coat goes into the still-wet first, driving the material deeper. A saturating, runny application is the goal rather than a thin painted-out film. Protect adjacent glass, aluminium, glazed tiles and vegetation from splashes and overspray, keep good ventilation and observe solvent fire-safety measures, and always confirm coverage, coat count and curing details against the current STP technical data sheet and a site mock-up, as porous substrates absorb very different quantities.
Specifications
| Product type | Solvent-based silane/siloxane penetrating water repellent (Silicon Water Peller) |
| Base chemistry | Blended silane / siloxane in an organic solvent carrier |
| Appearance | Clear, colourless liquid; leaves no visible film |
| Function | Hydrophobic pore impregnation of concrete, brick, stone and masonry |
| Application method | Low-pressure spray, brush or roller, two wet-on-wet flood coats |
| Number of coats | Minimum two, applied wet-on-wet |
| Suitable substrates | Concrete, cement render/plaster, brick, stone and other porous mineral surfaces |
| Breathability | Water-vapour permeable; repels liquid water while allowing the substrate to dry |
| Not recommended for | Below-grade tanking, water-retaining or potable-water contact surfaces |
Industry use cases
Commercial and residential facades
Invisible water-repellent protection for exposed concrete and brick elevations on high-rise and mid-rise buildings, reducing damp ingress and staining without altering the look.
Heritage and architectural masonry
Preserves the natural appearance of fair-face brickwork and stone on heritage structures while shedding driving rain and slowing weathering.
Coastal and marine-exposed structures
Reduces chloride-laden water ingress into concrete near the coast, helping delay reinforcement corrosion as part of a durability strategy.
Infrastructure and precast
Water-repellent treatment for precast panels, boundary walls, parapets and exposed concrete on bridges and public structures.
Repair and refurbishment
Applied after crack repair and cleaning to cut future water uptake on ageing facades and render, extending the interval before the next intervention.
Frequently asked questions
Is ShaliKote SWP a bituminous coating?
Will it change the colour or finish of my brick or concrete?
Can I use it to waterproof a basement or water tank?
Does it stop cracks from leaking?
How is it applied and how many coats are needed?
Does the treated surface still breathe?
How we position STP ShaliKote SWP
ShaliKote SWP sits in STP’s chemical-waterproofing range as the clear, penetrating water repellent for above-grade facades, and it pairs naturally with the rest of STP’s system rather than competing with it. Where a surface has active leaks, construction joints or below-grade exposure, it should be read alongside STP’s integral and membrane systems such as the ShaliKote bituminous coatings for damp-proofing and STP’s crystalline and integral waterproofing admixtures for the structure itself, with SWP reserved for the finished, exposed mineral surface. Through Space Arc Engineering you can also specify equivalent silane/siloxane impregnations from our other brands where a project standard calls for them, including Dr. Fixit and Sika facade water repellents, and Fosroc’s Dekguard clear impregnation range for anti-carbonation-led durability schemes. Choosing between them usually comes down to the specified brand system, whether anti-carbonation classification is required, and whether a water-based or solvent-based carrier is preferred for the substrate density.
Fosroc Dekguard S — Specify the Fosroc option when the project calls for a branded silane/siloxane hydrophobic impregnation with recognised anti-carbonation and chloride-resistance credentials as part of a concrete-durability specification.
Related Waterproofing products
Source STP ShaliKote SWP for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.