Single-skin profiled steel cladding
Single-skin steel sheeting is used as the outer weatherskin (roof and wall) and inner liner in built-up cladding systems. Profile depth, cover width, and minimum roof pitch vary by product. Data is sourced from manufacturer technical data sheets and public product information. Spanning data depends on gauge, load zone, and support spacing — obtain current load tables from the manufacturer.
| Profile | Manufacturer | Depth (mm) | Cover width (mm) | Gauges (mm) | Min roof pitch (°) | Use | Notes |
|---|---|---|---|---|---|---|---|
| AS13/3 Corrugated | Steadmans | 18 | 991 | 0.5, 0.7 | — | Roof, Wall | Sinusoidal corrugated, traditional look |
| AS20/1000 | Steadmans | 20 | 1000 | 0.4, 0.5, 0.7 | — | Liner, Wall | Shallow trapezoidal, used as liner in twin-skin systems |
| AS24/1000 | Steadmans | 24 | 1000 | 0.5, 0.7 | — | Roof, Wall | Medium trapezoidal |
| AS30/1000 | Steadmans | 30 | 1000 | 0.5, 0.7 | — | Roof, Wall | Deep trapezoidal |
| AS35/1000 | Steadmans | 35 | 1000 | 0.5, 0.7 | — | Roof, Wall | Deepest Steadmans profile, matches AS35 insulated panel |
| 13/3 Corrugated | Cladco | 18 | 990 | 0.5, 0.7 | 10° | Roof, Wall | 13 round corrugations per sheet |
| 32/1000 Box Profile | Cladco | 32 | 1000 | 0.5, 0.7 | 4° | Roof, Wall | 6 ribs across sheet. Most popular box profile. |
| 34/1000 Box Profile | Cladco | 34 | 1000 | 0.5, 0.7 | 4° | Roof, Wall | 7 ribs across sheet. Strongest box profile in range. |
| 41/1000 Tile Form | Cladco | 41 | 1000 | 0.6 | 12° | Roof | Pantile effect for domestic/aesthetic use |
| 30/500 Standing Seam | Cladco | 30 | 500 | 0.7 | 6° | Roof, Wall | Secret fix. A1 fire rated. Modern architectural aesthetic. |
| 13.5/3 Sinusoidal | Tata Steel | 19 | 990.6 | 0.7 | — | Roof | Traditional corrugated profile |
| R32 Trapezoidal | Tata Steel | 32 | 1000 | 0.7, 0.9 | — | Roof | Standard roof weathersheet for Trisobuild system |
| R35 Trapezoidal | Tata Steel | 35 | 900 | 0.7 | — | Roof | Narrower cover width |
| R46 Trapezoidal | Tata Steel | 46 | 900 | 0.7, 0.9 | — | Roof | Deep profile for long spans |
| CL19 Wall | Tata Steel | 19 | 1000 | 0.5 | — | Wall | |
| C32 Wall | Tata Steel | 32 | 1000 | 0.5, 0.7 | — | Wall | |
| C46 Wall | Tata Steel | 46 | 900 | 0.5, 0.7, 0.9 | — | Wall | |
| LP1000 Liner | Tata Steel | 25 | 1000 | 0.4 | — | Liner | |
| RL32 Liner | Tata Steel | 32 | 1000 | 0.7 | — | Liner | |
| Colorcoat Urban 514 | Tata Steel | 25 | 514 | 0.5 | 5° | Roof, Wall | Made-to-measure standing seam kit system. BBA certified. |
| Colorcoat Urban 305 | Tata Steel | 25 | 305 | 0.5 | 5° | Roof, Wall | Narrower panels for tall/exposed buildings |
| TPP 1000-32 Box Profile | Thomas Panels | 32 | 1000 | 0.5, 0.7 | — | Roof, Wall | Capillary groove eliminates need for sealing strips. Single skin, overcladding, or layered insulated system. |
| TPP 34/1000 Box Profile | Thomas Panels | 34 | 1000 | 0.5, 0.7 | 4° | Roof, Wall | 7 profiles across sheet. Most common for industrial/agricultural/commercial. |
| TPP 14/3 Corrugated | Thomas Panels | 14 | 990 | 0.5, 0.7 | — | Roof, Wall | Traditional sinusoidal corrugated profile. |
| LTP20 | Lindab | 18 | 1026 | 0.5, 0.6, 0.7 | — | Roof | Trapezoidal roof profile. Anti-condensation felt option available. |
| LTP35 | Lindab | 33 | 954 | 0.5, 0.6, 0.7 | — | Roof | Trapezoidal. Water-blocking grooves at overlaps. |
| LTP45 | Lindab | 43 | 900 | 0.5, 0.6, 0.7 | — | Roof | Deep trapezoidal. Good load-bearing capacity for larger buildings. |
| LLP20 | Lindab | 18 | 1000 | 0.5, 0.6, 0.7 | 14° | Roof, Wall | Equilateral (symmetrical wave) profile. |
| LVP20 | Lindab | 20 | 1026 | 0.5, 0.6, 0.7 | — | Wall | Trapezoidal wall sheeting. Wide peaks, narrow valleys. |
| SIN18V | Lindab | 18 | 1066 | 0.5, 0.6, 0.7 | — | Wall | Sine wave wall profile. |
| SIN26 | Lindab | 26 | 1000 | 0.5, 0.6, 0.7 | — | Roof, Wall | Sine wave profile for roof and wall. |
| SRP25N Standing Seam | Lindab | 25 | 500 | 0.6 | 12° | Roof | Click-together standing seam (Coverline range). No special tools needed. Compatible with LindabSolarRoof. Up to 30yr warranty. |
| PLX Standing Seam | Lindab | — | — | 0.5, 0.6 | — | Roof, Wall | Premium standing seam from coil (Seamline range). Bio-based BT coating. 350g Zinc/m2. Workable to -15C. For premium architectural applications. |
Coating systems comparison
The finish (coating system) on a steel cladding profile affects its service life, maintenance requirements, and cost. Common finishes used on UK single-skin and composite profiles are shown below.
| Finish | Manufacturer | Typical warranty (years) | Substrate | Typical use |
|---|---|---|---|---|
| Colorcoat HPS200 Ultra | Tata Steel | 40 | Galvalloy | Premium long-life, harsh environments |
| Colorcoat Prisma | Tata Steel | 30 | Galvalloy | Metallic/pearlescent architectural |
| Colorcoat LG (Plastisol) | Tata Steel | 25 | Galvanised | Standard commercial/industrial |
| GreenCoat Pural BT | SSAB | 40 | Galvanised | Standing seam, tile form |
| PVC Plastisol (generic) | Various | 20 | Galvanised | Tough leathergrain, good value |
| Polyester paint | Various | 12 | Galvanised | Economy, light-duty |
| Plain galvanised | Various | 15 | Zinc | Agricultural, budget |
| Kingspan XL Forte | Kingspan | 40 | Steel | Insulated panels, wide colour range |
Common questions
What profile types are used for portal frame roofs and walls?
The most common profiled steel sheets for UK portal frame buildings are trapezoidal (box profile) sheets in the 32mm–35mm depth range, with a 1000mm cover width. Corrugated profiles (sinusoidal, 76mm pitch) are also used, particularly in agricultural buildings. Liner sheets (shallow trapezoidal, 20mm depth) are used as the inner skin in twin-skin systems where insulation quilt is installed between the skins.
What is the minimum roof pitch for box profile cladding?
Most box profile (trapezoidal) sheets have a minimum recommended roof pitch of 4°, which equates to approximately 70mm per metre of run. Corrugated sheets typically require a minimum of 10°. Below these pitches, wind-driven rain can penetrate the laps. Always check the manufacturer's current installation guidelines, as minimum pitch can vary by profile depth and installation method.
What is the difference between roof and liner profiles?
Roof profiles (outer weatherskin) have a deeper cross-section for spanning capacity and are coated on the outer face for weather resistance. Liner profiles are shallower and lighter, designed to span between secondary steelwork on the inner face of the building. In twin-skin built-up systems, insulation quilt is supported on the liner and compressed by the outer sheet at the purlins.
What gauges are typically used for portal frame roofing?
0.7mm is the most common gauge for commercial and agricultural portal frame roofing in the UK. 0.5mm is used in low-load conditions and for liner sheets. Some specialist profiles are available in 0.9mm for heavy-duty or long-span applications. Thicker gauges increase spanning capacity but add weight and cost. The appropriate gauge depends on the structural span tables and the applied load from the design wind and snow conditions.