Built different.
Tested to prove it.
A layer-by-layer breakdown of how Cuirass steel doors achieve fire resistance, forced-entry protection and thermal efficiency simultaneously — without aesthetic compromise.
Inside a Cuirass door
Six layers. Each one earns its place.
CRCA cold-rolled steel sheet, galvanised to IS 277 G90. Zero porosity surface for powder coat adhesion.
Fire-retardant rockwool (60–120 min) or structural honeycomb. Selection depends on fire-rating requirement.
Eliminates cold bridging in frame section. Brings door-set U-value to ≤ 0.9 W/m²K.
Interior face sheet — can accept wallpaper, veneer or high-gloss lacquer laminate.
Continuous lock rail spanning full door height. Houses 5- or 11-point bolt mechanism with hardened inserts.
UV-cured at 200°C. Passes 1000 h salt-spray per ISO 9227. Colour-matched to any RAL or NCS shade.
Series comparison
Choose the right series for your project at a glance.
| Specification | G-Series Residential | T-Series Commercial | WPC Series Decorative |
|---|---|---|---|
| Leaf thickness | 45 mm | 55 mm | 38 mm |
| Max leaf width | 1100 mm | 1200 mm | 1000 mm |
| Max leaf height | 2400 mm | 2700 mm | 2400 mm |
| Steel gauge | 1.25 mm GI | 1.25 mm GI | WPC Core |
| Core fill | Honeycomb | Rockwool | WPC |
| U-value | ≤ 1.1 W/m²K | ≤ 0.9 W/m²K | ≤ 1.3 W/m²K |
| Fire rating | — | EI 60–120 | — |
| Security class | RC1 | RC2 (EN 1627) | RC1 |
| Lock points | 5 | 11 | 5 |
| Frame type | Pre-hung | Pre-hung | Loose frame |
| Warranty | 7 years | 10 years | 5 years |
Certifications & standards
Every certificate available on request. We ship a compliance dossier with each project order.
Manufacturing quality management system
Resistance class 2 — burglar resistance
Steel door frames — dimensional & quality
Flush door shutters — structural
60 & 120 min fire resistance — IS 3614 Part 2
External windows and doors — performance
Questions architects ask us
Why steel over wood?
Steel does not warp, shrink, swell or rot. A Cuirass door fitted in 1998 still operates to tolerance today. Timber requires refinishing every 3–5 years and eventually delaminates.
How is fire rating achieved?
Rockwool core slows heat transfer. Intumescent strips in the rebate swell at 150 °C to seal the gap. The combination prevents passage of flames and hot gases for the rated duration.
What does RC2 mean?
EN 1627 Resistance Class 2 means the door withstands 3 minutes of attack by an experienced burglar using crowbars and wedges. Most Indian residential locks are unrated.
Can I specify custom sizes?
Yes. Non-standard widths and heights are our norm. Leaf widths from 600 mm to 1200 mm and heights up to 2700 mm are in standard production scope. Submit a drawing for pricing.
Is powder coat maintenance-free?
Correct. The electrostatic coat is UV-cured at 200 °C and passes 1000-hour salt-spray testing. A damp cloth annually is sufficient. The colour is guaranteed for 10 years.
Do you supply CAD and BIM files?
All G and T-Series doors are available in DWG (AutoCAD), RVT (Revit) and IFC format. Our NBS specification clause can be pasted directly into your architect's spec.