UltraTech Basekrete
Polymer-modified, pre-mixed high-strength mortar for thick plaster, masonry jointing and old-surface repair — builds up to 25 mm in a single layer.
What is it?
A cement-based, polymer-modified, factory pre-mixed multipurpose mortar in 40 kg bags. Add 14-16% water on site and it is ready for plastering, jointing and repair duty.
Where is it used?
Thick internal and external plaster on masonry, old-surface repair, brick and block laying, and high-demand wet areas such as swimming pools, water tanks, foundations and basements.
Why use it?
It delivers 20-25 N/mm2 compressive strength at 28 days with a 15-25 mm single-layer build — well beyond what site-batched plaster reliably achieves — with factory-graded sand for batch consistency.
How is it applied?
Trowel or spatula application onto a clean, roughened substrate; level with aluminium floats, allow 48 hours before follow-on work and water-cure for 2-3 days.
About UltraTech Basekrete
Anyone who has watched a 20 mm site-batched plaster coat sag off a wall, or crack as it dries, knows the weakness is rarely the cement — it is the sand grading and the water the mason adds by eye. UltraTech Basekrete removes both variables. It arrives as a factory pre-mixed blend of cement, redispersible polymer and well-graded sand and fillers, so every 40 kg bag behaves the same way. The crew adds only 14-16% clean water by weight, mixes mechanically for two to three minutes, and gets a lump-free mortar with roughly an hour of pot life.
Basekrete is deliberately multipurpose. On new masonry it works as a high-strength plaster and a brick or block jointing mortar; on renovation jobs it serves as a polymer-modified repair mortar over old, hacked or damaged surfaces. UltraTech specifically positions it for areas where ordinary plaster struggles — inside swimming pools, water tanks, foundation zones and basements — and as an underlayment plaster that gives tile adhesives a strong enough base to carry large-format tiles on vertical surfaces. Technical parameters comply with IS 2250, and Space Arc supplies it ex-stock across Delhi NCR with pan-India dispatch.
The technical insight
The working mechanism is the redispersible polymer. When the mortar is mixed, polymer particles disperse in the gauging water; as the cement hydrates and the mix loses moisture, they coalesce into a film that interpenetrates the hardening cement matrix. That co-cured film does three things a plain cement-sand mix cannot: it grips the substrate (bond, not just suction), it bridges micro-cracks as drying shrinkage develops, and it reduces the water needed for workability — which is why 14-16% water yields a mortar that stands 25 mm thick without slumping. The factory-graded aggregate does the rest: a dense, continuous particle packing that supports the wet layer and drives the 20-25 N/mm2 28-day strength. For higher-volume work, the TDS permits extending the mix 1:1 by weight with clean M-sand or river sand.
Where it is used
- Thick internal and external plaster (15-25 mm) on brick and block masonry where high strength is specified
- Brick and block laying — a polymer-modified jointing mortar from the same bag as the plaster
- Repair of old, damaged or hacked plaster and rendered surfaces during renovation and rehabilitation
- Plastering inside swimming pools and water tanks ahead of the waterproofing or finishing system
- Foundation and basement plaster where dampness and abrasion punish ordinary cement mortar
- Underlayment plaster beneath tile adhesives to carry large-format or heavy tiles on vertical surfaces
- Building out deep patches, chases and conduits in successive 25 mm layers
Key advantages
- Builds 15-25 mm in a single layer without sagging — fewer coats than conventional plaster
- Polymer-modified bond to concrete and masonry, with reduced shrinkage cracking versus site-batched mortar
- 20-25 N/mm2 compressive strength at 28 days, achieved without any extra aggregate
- Factory-graded sand and fillers give every bag identical workability — no site-batching disputes
- Water-only mixing with roughly one hour of pot life suits realistic site pace
- Extendable 1:1 with M-sand or river sand (per the TDS) for economical high-volume work
- Ready for follow-on trades after 48 hours, weather and thickness permitting
- Non-toxic and non-flammable, with lower wastage than loose cement-sand batching
Limitations & considerations
- Single-layer thickness is capped at 25 mm; deeper build-ups need multiple layers with a 48-hour wait between them
- It is a plaster and repair mortar, not a structural concrete repair — specified structural reinstatement calls for micro-concrete or a dedicated repair system
- Do not apply if the temperature may drop below 5 deg C or exceed 50 deg C during application and early cure
- Pot life is about one hour, so mix only what the crew can place — retempering stiffened mortar is not an option
- It still needs conventional water curing (2-3 days, extended in hot weather); it is not self-curing, and it is not a waterproofing coating by itself
Selection & best practice
Start with the substrate: it must be clean and free of oil, grease and paint, with defects deeper than 25 mm patched first. On smooth concrete, create mechanical roughness — the polymer helps adhesion, but it cannot rescue a polished surface. Mix a full or half bag at a time with 14-16% water by weight using a mechanical stirrer for 2-3 minutes; hand mixing leaves lumps and inconsistent water content. Apply by trowel or spatula in 15-25 mm, striking the final level with aluminium floats or levellers. For thicker sections, build in layers, allowing a minimum of 48 hours before the next application or any follow-on work. Water-cure for 2-3 days at about three cycles a day, and extend curing in hot Indian summer conditions. Run a small site trial before full-scale use, and confirm values against the current batch TDS.
Specifications
| Compressive strength @ 28 days (no added aggregate) | 20-25 N/mm2 |
| Application thickness per layer | 15-25 mm |
| Water : powder ratio | 14-16% by weight |
| Pot life | Approx. 1 hour |
| Coverage at 12 mm thickness | 0.40 sq ft per kg (approx. 16 sq ft per 40 kg bag) |
| Bulk density | 1550-1650 kg/m3 |
| Subsequent usage time | 48 hours minimum (thickness, temperature and humidity dependent) |
| Standard compliance | Technical parameters comply with IS 2250 |
| Packaging / shelf life | 40 kg bag; 12 months in cool, dry storage |
Industry use cases
Residential & High-Rise Construction
Thick external plaster on AAC block and brick facades where contractors want consistent strength floor after floor, without depending on site sand quality.
Swimming Pools & Clubhouses
Pool shell and deck plastering that gives the waterproofing and tiling systems a hard, well-bonded base able to tolerate permanent wet service.
Basements & Foundations
High-strength plaster in below-grade areas where damp, backfill pressure and abrasion break down ordinary cement mortar early.
Renovation & Rehabilitation
Re-plastering hacked or spalled surfaces in occupied buildings, where polymer-modified bond to old substrates decides whether the repair lasts.
Large-Format Tile & Stone Cladding
Underlayment plaster that brings walls to line and level with enough strength for adhesives carrying heavy or oversized tiles.
Frequently asked questions
How much area does one 40 kg bag of Basekrete cover?
How is Basekrete better than site-mixed cement-sand plaster?
Can I add sand to stretch the material on big jobs?
Is Basekrete waterproof? Can I use it alone in a water tank?
How long before I can tile or paint over it?
Does Basekrete come in different strength grades?
How we position UltraTech Basekrete
Within the UltraTech Building Products range, Basekrete is the heavy-duty base layer: pair it with UltraTech Super Stucco for the smooth finishing coat, and with the UltraTech Tilefixo adhesive range when it serves as underlayment for large-format tiles. For structural-grade reinstatement beyond a 25 mm plaster repair, step up to a micro-concrete or the Fosroc Renderoc repair family we stock. In pools and tanks, combine Basekrete with Fosroc or Dr. Fixit waterproofing systems — the mortar provides strength and substrate, not the water barrier. Space Arc’s technical team can match the grade and system build-up to your specification.
Related Concrete Repair products
Source UltraTech Basekrete for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.