Sika SikaTop-122 HS
One-component, polymer-modified repair mortar that patches spalled and damaged concrete up to 40 mm thick per pass — just add water, apply by hand or wet spray.
What is it?
A factory-blended, one-component polymer-modified cementitious mortar for repairing spalled, cracked and damaged concrete; you mix only water on site.
Where is it used?
Beams, columns, slabs, soffits, bridge decks, tunnels and infrastructure where cover concrete has spalled or reinforcement has corroded.
Why use it?
Bonds tightly to sound concrete, builds up to 40 mm in a single vertical or overhead pass, and cuts the mixing errors that come with two-part or site-batched mortars.
How is it applied?
Prepare the substrate to SSD, prime if required, gauge with clean water, then trowel or wet-spray in layers and cure.
About Sika SikaTop-122 HS
SikaTop-122 HS is Sika India’s single-component, polymer-modified concrete repair mortar. It arrives as a grey powder in which portland cement, a redispersible polymer, graded aggregates and performance additives are already blended in the correct proportions, so the only variable left on site is the water you add. That single-pack format is the practical selling point: there is no separate liquid component to store, measure or mismeasure, which makes it a dependable choice for repair crews working across scattered sites where consistency is hard to police.
The mortar is built for patch and reinstatement work on structural and cosmetic concrete — the everyday reality of spalled soffits, honeycombed pours, carbonated cover and reinforcement that has started to rust and blow the concrete off. It can be worked by traditional hand-trowelling or pumped through wet-spray equipment, and it holds on vertical and overhead faces in layers up to 40 mm without a separate formwork operation. For contractors, consultants and facility owners in Delhi NCR and across India, that combination of a proven Sika formulation and a forgiving one-bag mix is what keeps repair schedules moving.
The technical insight
The performance comes from the redispersible polymer dispersed through the cement matrix. When the powder is gauged with water the polymer film-forms alongside cement hydration, threading a flexible network between the hardening crystals. That polymer network does three things at once: it wets and grips the prepared substrate for a strong bond to the parent concrete, it holds water in the mix so the cement hydrates more completely instead of drying out in a thin patch, and it reduces the drying shrinkage that causes plain sand-cement mortars to debond and craze at the edges. The graded aggregate skeleton keeps the section dimensionally stable while the fresh mortar stays cohesive and thixotropic enough to be built up to 40 mm on a vertical or overhead face without slumping. The result is a repair that behaves as a monolithic extension of the substrate rather than a separate skin sitting on top of it — which is precisely what determines whether a patch repair lasts years or fails within a season.
Where it is used
- Reinstating spalled and delaminated cover concrete on beams, columns and slabs
- Repairing areas of corroded, exposed reinforcement after rust removal and priming
- Patching honeycombed, segregated or poorly compacted concrete pours
- Overhead and vertical repairs on soffits and beam undersides where sag resistance matters
- Bridge deck, pier and abutment repairs in transport infrastructure
- Tunnel, underground and water-retaining structure repairs
- Making good pockets, tie-holes and blockouts left after formwork strike
- Cosmetic surface reinstatement ahead of protective coatings or anti-carbonation systems
Key advantages
- Single-pack — only water is added on site, removing the risk of wrong two-part ratios
- Builds up to 40 mm in a single vertical or overhead layer, so fewer passes are needed
- Polymer modification gives strong adhesion to sound, prepared concrete
- Low shrinkage compared with plain sand-cement mortars, reducing edge cracking and debonding
- Applies by hand trowel or wet-spray machine to suit crew size and access
- Cohesive, sag-resistant consistency holds on vertical and overhead faces
- Consistent factory blending means repeatable results across scattered repair sites
- Portland-cement base is compatible with concrete substrates and later Sika coating systems
Limitations & considerations
- A repair mortar, not a structural strengthening system — it reinstates section but does not add load capacity like plates or wraps
- Vertical build is capped at 40 mm per layer; deeper losses need multiple passes or a formed micro-concrete
- Bond depends entirely on correct substrate prep — laitance, dust, oil or a dry substrate will cause failure
- Requires proper curing; patches left to dry out in heat or wind will shrink and crack
- Not a general-purpose plaster or a self-levelling floor topping — it is a targeted concrete repair mortar
- Working time is limited once gauged, so mix only what the crew can place within the pot life
Selection & best practice
Start by cutting back to sound concrete and squaring the edges — feathered edges peel. Remove all laitance, dust, oil and loose material, expose and clean any corroded steel back to bright metal, and treat the reinforcement with an appropriate zinc-rich or cementitious primer. Bring the substrate to a saturated-surface-dry (SSD) condition and, where maximum adhesion is required, apply a Sika bonding bridge such as SikaTop Armatec-110 EpoCem or a Sikadur epoxy primer and work the mortar in wet-on-wet. Gauge the powder with clean water at the recommended ratio using a slow-speed paddle to avoid entraining air, then build the mortar in controlled layers up to 40 mm, compacting firmly against the substrate. Mix only what can be placed within the pot life, finish before initial set, and cure the repair — damp curing or a curing membrane — to prevent shrinkage cracking. Do not apply in temperatures outside +5°C to +40°C.
Specifications
| Product type | One-component, polymer-modified cementitious repair mortar |
| Chemical base | Portland cement, redispersible polymer powder, selected aggregates and additives |
| Appearance | Grey powder (add water on site) |
| Compressive strength (28 days) | ~55 N/mm² |
| Maximum layer thickness | Up to 40 mm per layer (vertical / overhead) |
| Fresh mortar / bulk density | ~1.3 kg/l at 27°C |
| Water demand | ~0.13 by weight (~3.9 litres per 30 kg bag) |
| Pot life | ~30 minutes at +20°C |
| Application | Hand trowel or wet-spray machine |
| Packaging | 30 kg bags |
| Application temperature | +5°C to +40°C |
| Shelf life | 6 months from production, stored dry in sealed packaging |
Industry use cases
Bridges & Highways
Reinstating spalled deck soffits, piers and crash-barrier plinths where salt and carbonation have driven cover loss and rebar corrosion.
Commercial & Residential Buildings
Repairing spalled beams, columns and slab soffits in ageing RCC frames before applying protective or anti-carbonation coatings.
Water & Wastewater
Patching cover concrete in tanks, sumps and channels where reinforcement has begun to corrode in aggressive, damp conditions.
Industrial Plants
Making good machine-base pockets, damaged edges and structural concrete in factories with minimal downtime using rapid hand or spray repair.
Tunnels & Infrastructure
Overhead and vertical concrete reinstatement in tunnels and underground structures where sag-resistant, single-pack mortar speeds up work.
Frequently asked questions
Is SikaTop-122 HS a one-component or two-component mortar?
How thick can I apply it in a single pass?
Do I need a bonding primer?
Can it be machine-sprayed?
What pack size and coverage should I plan for?
Will it strengthen a structurally deficient member?
How we position Sika SikaTop-122 HS
SikaTop-122 HS sits in Space Arc’s concrete repair and rehabilitation range as the go-to single-pack patching mortar for spalled and damaged concrete. Within the Sika family it pairs naturally with SikaTop Armatec-110 EpoCem as a bonding bridge and reinforcement primer, with Sika MonoTop reprofiling mortars for larger repair schemes, and with Sikagard anti-carbonation coatings to protect the finished repair. Where the underlying member also needs added capacity — not just reinstated concrete — it is complemented by Sika’s structural strengthening systems such as Sika CarboDur laminates and SikaWrap fabrics. Against other brands we carry, it competes with Fosroc’s Renderoc range and MC-Bauchemie’s Nafufill repair mortars, so specifiers can standardise on whichever ecosystem their project already uses.
Fosroc Renderoc HB40 — A specifier working to a Fosroc-approved schedule can choose Renderoc HB40 as the direct equivalent — a single-component, polymer-modified mortar also placed up to 40 mm in vertical and overhead repairs and classified to EN 1504-3.
Related Concrete Repair products
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