MC-Bauchemie MC-Plaster
A WTA-certified three-coat render system engineered to store crystallising salts, keep vapour moving outward, and stop repaired damp walls from blistering and re-staining within a season.
What is it?
MC-Plaster is a factory-batched, cement-lime restoration render system built as three purpose-matched coats rather than one all-purpose plaster: a bonding spray coat (VSM), a macro-porous salt-storage base coat (PGP), and a hydrophobic finish coat (WPW or Basic WP).
Where is it used?
Rising-damp basements and plinths, salt-efflorescing heritage masonry, coastal and saline-groundwater boundary walls, and any wall where ordinary cement plaster keeps blistering and staining again after re-plastering.
Why use it?
Ordinary sand-cement plaster traps migrating salts just behind its surface, so it hollows out, blisters and re-stains within a year or two on a genuinely damp wall. MC-Plaster’s render body is built to store that salt crystallisation away from the finish coat while a high vapour diffusion rate lets wall moisture keep evaporating outward instead of building pressure under the skin.
How is it applied?
Hand or machine applied in WTA sequence: bonding coat, salt-storage base coat built up to roughly 30mm in a single layer where needed, then a hydrophobic finish coat, onto sound masonry stripped of old plaster with the damp source ideally corrected first.
About MC-Bauchemie MC-Plaster
MC-Plaster belongs to MC-Bauchemie’s masonry restoration range, alongside Nafufill repair mortars and the Exzellent and Oxal render lines used for lime, thermal and moisture-regulation rendering. Where MC-Plaster differs is its WTA certification and salt-storage engineering, built for masonry where rising damp has already deposited sulphates and chlorides, not for cosmetic re-plastering of dry surfaces. Space Arc specifies it as part of a repair sequence, alongside injection damp-proofing and drainage correction, rather than as a standalone fix.
The distinction that matters on site is “waterproof” versus “salt-storage.” A polymer-modified waterproof plaster seals the surface and looks fine until trapped salts crystallise behind the seal and push it off in sheets. MC-Plaster’s base coat is deliberately macro-porous, so salt crystals form inside large pore spaces within the render body where crystallisation pressure does no visible damage, while high vapour permeability keeps letting residual wall moisture escape.
The technical insight
The bonding coat (VSM) and finish coat (WPW) are rated to mortar class CS IV and CS II respectively under EN 998-1, with the alternate Basic WP finish rated CS IV under DIN EN 998-2; the base coat (PGP) can be built up to roughly 30mm in a single layer. All three coats carry WTA certification, the German scientific-technical association benchmark that conservation engineers treat as the reference standard for restoration renders — a more specific, salt-storage-focused proof point than routine plastering codes are written to test for. Composition (per the manufacturer’s safety data sheet) is a mineral cement-lime mortar: roughly 50-70% calcium carbonate, 20-30% Portland cement (low chromate), and 3-10% calcium hydroxide, supplied as a one-component, factory-batched powder gauged with water on site.
Where it is used
- Rising-damp and salt-efflorescing basement or plinth walls
- Heritage building, temple and haveli restoration on salt-laden masonry
- Coastal and saline-groundwater boundary and retaining walls
- Industrial plinth walls exposed to effluent or saline splash
- Re-plastering after chemical or physical DPC injection
- Old load-bearing masonry with recurring hollow, blistering plaster
- Government and institutional heritage facade restoration
- Basement walls in high-water-table sites
Key advantages
- Purpose-built three-coat system matched to the actual damp/salt problem, not a generic plaster
- Genuine WTA-tested salt-storage capacity, not just a surface waterproofing claim
- High water-vapour diffusion keeps walls drying out instead of trapping moisture
- Hydrophobic finish sheds wind-driven rain while remaining breathable
- Highly sulphate-resistant formulation suited to coastal and saline groundwater
- WTA certification carries real weight on conservation and heritage-sensitive tenders
- One-component, factory-batched consistency reduces site batching error
- Hand or machine/spray application gives contractors flexibility on large facades
Limitations & considerations
- Does not fix the damp source; skipping DPC injection or drainage correction eventually overloads the render’s storage capacity
- Multi-coat specialist system needing applicators trained in WTA sequencing, not a one-coat quick fix
- Not a routine India shelf item; typically project-indented through the authorised distributor, so lead time needs planning
- Costs more than ordinary sand-cement or basic waterproof plaster
- Exact coverage, dosage and pack-size figures are project-specific and must be confirmed from current TDS, not assumed on site
- Overkill for cosmetic re-plastering of masonry that is not genuinely salt or damp affected
Selection & best practice
Test the wall’s salt content before choosing the finish coat, and correct the actual moisture source before or alongside plastering. Hack off existing plaster to sound masonry roughly 80cm above the visible salt/damp line, brush and wash down loose material, and apply the full three-coat sequence rather than substituting a single coat to save time. Avoid gypsum-based fillers over the system and let each coat cure per schedule before the next. Space Arc’s site team can run the salt assessment and coat selection as part of the specification.
Specifications
| System type | 3-coat WTA salt-storage restoration render (bonding + base + finish coats) |
| Base chemistry | Cement-lime mineral mortar (Portland cement, calcium hydroxide, calcium carbonate) |
| Certification | WTA-certified system product (all coats) |
| Bonding coat (VSM) | Mortar class CS IV per EN 998-1; highly sulphate resistant |
| Base coat (PGP) | Mortar class CS II per EN 998-1; up to ~30mm in a single layer; high salt-storage capacity |
| Finish coat (WPW) | Mortar class CS II per EN 998-1; hydrophobic; high water-vapour diffusion |
| Alternate finish (Basic WP) | Mortar class CS IV per DIN EN 998-2; hydrophobic |
| Application | One-component, factory-batched; hand or machine/spray applied |
| Form | Powder, water-gauged on site |
Industry use cases
Heritage/Conservation
A haveli in a saline-groundwater zone where earlier cement re-plastering had blistered off twice
Residential basements
A basement wall rehabilitated after DPC injection, needing a breathable render over treated masonry
Coastal residential
A coastal bungalow’s boundary wall that kept staining and flaking every monsoon
Industrial
A plinth wall exposed to saline effluent splash near a process area
Institutional/Government
An old government building facade under conservation-grade restoration
Frequently asked questions
Does MC-Plaster stop rising damp on its own?
Can MC-Plaster go directly over old cement plaster?
Which finish coat do I need, WPW or Basic WP?
Is this the same as a normal waterproof plaster?
How is it supplied in India?
What surface preparation does it need?
How we position MC-Bauchemie MC-Plaster
Within MC-Bauchemie’s own range, MC-Plaster sits next to the Exzellent and Oxal render systems and Nafufill repair mortars; specifiers choose MC-Plaster when WTA-certified salt-storage performance is the requirement, and Exzellent or Oxal when the brief is thermal, lime or general moisture-regulation rendering instead. Fosroc does not carry a direct WTA-certified salt-storage render equivalent in its India catalogue; its Renderoc range addresses concrete-side structural repair and Dryzone handles chemical DPC injection, both of which pair with, rather than substitute for, MC-Plaster on a full damp-masonry rehabilitation scope.
Related Concrete Repair products
Source MC-Bauchemie MC-Plaster for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.