Sika Latex
SBR Polymer Latex Bonding Agent and Polymer Admixture for Cement Mortars and Screeds
Authorized Project Distributor — Sika India | Space Arc Engineering, Ghaziabad
Product Overview
Sika Latex is a milky-white, styrene butadiene rubber (SBR) polymer latex emulsion from Sika for two complementary construction applications: as a bonding agent applied to existing concrete or masonry substrates before placing new cementitious mortar, floor screed, or repair material; and as a polymer modification admixture added to cement mortar, render, repair mix, or tile adhesive during mixing to improve adhesion, flexibility, reduced permeability, and durability. As a bonding agent, Sika Latex is mixed with cement and water in the ratio of 1 part Sika Latex to 1 part OPC to 1 part water to form a creamy slurry, which is scrubbed onto the prepared existing concrete surface and allowed to become tacky before the new cementitious material is placed wet-on-wet. The SBR polymer in the slurry bridges the interface between old and new concrete, preventing the delamination of floor screeds, repair mortars, and render coats placed without a bonding agent on an unprimed substrate. As a polymer admixture, Sika Latex replaces 20 to 30 per cent of the mortar gauging water, dispersing SBR polymer through the mix to coat cement hydration products and provide improved tensile and flexural strength, adhesion, and reduced permeability in the cured mortar. The critical applications for Sika Latex in India are: bonded floor screeds over concrete slabs (preventing the chronic screed delamination problem seen on Indian construction sites where screeds are placed without a bonding agent); SBR-modified waterproof render for external walls, podium decks, and wet area waterproofing; swimming pool render and finish coat; and polymer-modified tile adhesive beds for ceramic and stone tile installation. Space Arc Engineering distributes Sika Latex for concrete repair, floor screed, waterproofing, and general mortar modification projects across Delhi NCR, Ghaziabad, Noida, and Northern India.
Applications
- Floor screed bonding agent — SBR slurry applied to concrete slab before bonded cement screed
- Waterproof render — SBR-modified cement render for external walls and wet area waterproofing
- Concrete surface repair — polymer-modified mortar for surface cosmetic and structural patching
- Tile adhesive modification — Sika Latex added to neat cement tile adhesive for improved adhesion
- Swimming pool render — two to three coats of SBR-modified render for pool waterproofing
- SBR-modified render for bathroom, toilet, and kitchen wet area waterproofing before tiling
Key Advantages
- Dual function — bonding agent (SBR slurry) AND polymer mortar admixture in one product
- Prevents floor screed delamination — bonds screed monolithically to concrete substrate
- Reduces water permeability of cementitious mortar — waterproofing function
- Improves flexibility and crack resistance of cement mortar
- Single-component, water-based — easy to use, non-toxic, non-flammable on site
- Cost-effective SBR latex specification for bonded screeds, renders, and tile beds
Technical Data
| Type | Styrene Butadiene Rubber (SBR) polymer latex emulsion |
| Appearance | Milky white liquid |
| As Bonding Agent | 1 part Sika Latex : 1 part OPC : 1 part water by volume — scrub to substrate |
| As Admixture | Replace 20 to 30 per cent of gauging water with Sika Latex in mortar mix |
| Shelf Life | 12 months in sealed container, protect from frost and freezing |
| Coverage | Approximately 4 to 6 m2 per litre of Sika Latex as bonding slurry |
Get a Quote
+91 9999155255 | info@space-arc.com | Space Arc Engineering, Sahibabad, Ghaziabad
Frequently Asked Questions
What is the correct procedure for using Sika Latex as a floor screed bonding agent and what is the critical timing between slurry application and screed placement?
The Sika Latex floor screed bonding procedure has two key requirements: correct slurry preparation and correct wet-on-wet timing. Prepare the bonding slurry by mixing 1 part Sika Latex, 1 part OPC cement, and 1 part clean water by volume to a smooth, lump-free creamy consistency. Pour the slurry onto the prepared (clean, laitance-free, surface-dampened but not wet) concrete slab and scrub firmly into the surface with a stiff brush to fill all surface pores. The critical timing requirement is that the floor screed mix must be placed onto the Sika Latex slurry while the slurry is still in the wet-on-wet (tacky) state — typically 15 to 30 minutes after slurry application at 28 to 35 degrees in Indian conditions. At higher temperatures with strong wind, the window shortens to 10 to 15 minutes. If the slurry dries completely (turns white and powdery) before the screed is placed, it acts as a separation layer rather than a bonding agent — remove the dried slurry by brushing or compressed air, apply fresh slurry, and place the screed immediately. For large areas, divide the work into manageable zones and apply the bonding slurry to each zone immediately before placing the screed over that zone.
Can Sika Latex (SBR) replace Sikadur 32 (epoxy bonding agent) for structural concrete repair bonding?
Sika Latex SBR bonding agent and Sikadur 32 epoxy bonding agent both improve adhesion of new cementitious materials to existing concrete, but they provide very different levels of bond strength. Sika Latex SBR bonding slurry achieves approximately 0.8 to 1.2 MPa pull-off bond strength on well-prepared concrete — adequate for non-structural applications such as floor screeds, renders, and tile bedding. Sikadur 32 epoxy achieves 3 MPa or above — and structural concrete repair specifications (BS EN 1504, bridge and infrastructure repair codes) typically require a minimum 1.5 to 2.0 MPa pull-off bond strength. Sika Latex is NOT an appropriate substitute for Sikadur 32 in structural concrete repair applications, as the SBR bond strength is typically below the minimum required for structural repair. Additionally, SBR bonding slurry degrades in permanently wet or submerged conditions over time, while epoxy maintains full bond strength in all moisture conditions. Specify Sika Latex for standard floor screeds, waterproof renders, non-structural patching, tile adhesive modification, and swimming pool renders where the lower bond strength is adequate and the application is not in permanent chemical or water contact.
What is the mixing ratio of Sika Latex as a polymer admixture in a waterproof render for external walls and basement walls?
For SBR-modified waterproof render using Sika Latex as a polymer admixture, the standard addition rate is 1 part Sika Latex to 3 parts of the gauging water (1:3 SBR:water ratio) — for example, for a render mix requiring 3 litres of gauging water, replace 1 litre of water with Sika Latex and use only 2 litres of plain water. This 25 per cent polymer-to-water ratio provides sufficient SBR polymer content in the cured render (approximately 10 to 15 per cent polymer by cement weight) to meaningfully reduce permeability, improve adhesion, and increase flexibility compared to unmodified cement render. For a more intensively modified waterproof render (higher polymer content for demanding wet area or below-grade applications), the ratio can be increased to 1 part Sika Latex to 2 parts water (1:2 SBR:water ratio). Apply the SBR-modified render in two coats — a 6 mm scratchcoat allowed to firm up before the 10 to 15 mm finishing coat — over Sika Latex bonding slurry applied to the prepared concrete or masonry substrate. The SBR-modified render provides excellent weather resistance for external walls and adequate waterproofing for mild below-grade conditions; for basements under active hydrostatic pressure, supplement with SikaTop 107 Seal or a full membrane system.
Source Sika Latex for Your Project
Space Arc Engineering is an Authorized Project Distributor for Sika India serving Delhi NCR, Ghaziabad, Noida and Uttar Pradesh.
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