Product overview

The no purlin color steel tile mounting system is engineered to attach equipment directly to the standing seams or trapezoidal ribs of profiled steel sheets. The system consists of an aluminum or galvanized steel clamp base, a height-adjustable bracket, and a top rail or module clamp. It eliminates the need for transverse purlins, reducing material costs and installation time. The clamp mechanism utilizes a T-bolt and neoprene padding to secure the bracket without penetrating the roof membrane, preserving weather integrity. Load transfer occurs through the sheet’s ribs to the substructure. Standard compatibility includes profiles such as LSY-32/1000, YX25-210-840, and trapezoidal tiles with rib heights from 25mm to 75mm. The mounting system can support photovoltaic panels, cable trays, or light mechanical fixtures on metal roofs with slope angles between 5° and 45°.

≤45°Roof slope range
25-75mmCompatible rib height
M8 / M10Clamp bolt size
EN 1991-1-4Wind load design
Core advantages

Purlin elimination

Reduces secondary steel structure by 35-50% compared to traditional rail+purlins. Mounting brackets attach directly to roof sheet ribs, lowering material expenses and freight weight.

Waterproof integrity

Clamp design uses EPDM or silicone padding to seal the fixing point. No roof penetration reduces potential leaks. Tested to 600Pa watertightness under dynamic conditions.

Adjustable height and tilt

Integrated sliding mechanism allows vertical adjustment up to 40mm and tilt angle 0-15 degrees to compensate for roof irregularities or solar orientation.

Corrosion matched materials

Clamps in aluminum 6063-T5 (anodized AA15) or HDG steel (Z600 coating). Stainless steel A2-70 fasteners included for dissimilar metal contact prevention.

Product characteristics
Material options Extruded aluminum 6063-T5 (anodized 12-15μm) / Hot-dip galvanized steel S250GD+Z (275-600g/m²)
Clamp type Side clamp, mid clamp, end clamp for trapezoidal sheet; universal seam clamp for standing seam roofs
Rib compatibility Trapezoidal (height 25-75mm, pitch 150-350mm); corrugated (type R32, R45); sinusoidal profiles
Load capacity Ultimate tensile strength: clamp 2.5kN per bracket; design load: 1.2kN vertical / 0.8kN horizontal
Fastener specification Stainless steel A2-70 or A4-80 hex bolts; pre-assembled spring washer and flat washer
Temperature range -40°C to +110°C (EPDM seal maintains elasticity)
Fire classification Non-combustible, Class A according to ASTM E84, aluminum components
Certifications ISO 9001:2015; IEC 62852 (clamping force); TUV tested for wind uplift
Application scenarios
Industrial warehouses with trapezoidal color steel sheets – direct attachment of rooftop solar arrays (grid-tied PV systems).
Agricultural buildings (poultry farms, grain storage) – mounting exhaust fans, light brackets or small equipment without purlin grid.
Commercial metal roofs (carports, logistics centers) – supporting cable trays or low-profile walkways.
Retrofit projects on existing steel roofs – solution for adding loads without modifying primary structure.
Cooling systems and HVAC line sets fixed on corrugated metal cladding.
Technical notes & solutions

Wind uplift resistance

For roof zones with high suction, use additional locking clips and increase clamp density to 4 per square meter. Verify pull-out force via on-site pull test per ASTM E1512 (minimum 600 N per clamp).

Thermal movement of steel sheets

Color steel expands under thermal cycles. Use slotted bracket holes with friction pads that allow micro-slippage up to 3mm to avoid fastener fatigue. Do not overtighten beyond 15 Nm torque on M8 bolts.

Dissimilar metal contact

Aluminum brackets in contact with galvanized steel roof sheets require nylon isolators or non-conductive gaskets to prevent galvanic corrosion. Apply bituminous tape if isolator not used.

Seal integrity verification

After installation, inspect EPDM inserts for uniform compression. Gaps larger than 1.5mm indicate improper seating and may cause water ingress. Re-torque after 2 weeks.

Frequently asked questions
Q1 Is the no-purlin system suitable for all trapezoidal metal roofs?
Compatibility depends on rib height and spacing. Standard clamps fit rib heights 25-75mm and crest width 25-45mm. For custom profiles (butt ribs, narrow ribs), use profile-specific jaw adapters or custom-machined clamp inserts.
Q2 Does the mounting system require roof structural verification?
Yes. The roof sheet must support additional point loads. Provide load calculation based on sheet thickness (minimum 0.5mm steel), rib geometry, and span between primary purlins. The mounting system transfers load to sheet ribs; verify rib strength with manufacturer.
Q3 Can the system be used for solar panel installation without ground bonding?
Bonding is required by NEC 250. Use grounding clips or pre-installed grounding teeth in clamps to establish electrical continuity across brackets and roof frame. The anodized surface is non-conductive; remove coating at connection points or use star washers.
Q4 What maintenance is needed over time?
Inspect clamp torque annually (recommended 12-14 Nm for M8). Replace deteriorated EPDM pads every 8-10 years. Check for corrosion signs in coastal areas; apply protective spray if needed.
Ordering reference information

Part numbering scheme

NPCS-[Rib height code]-[Material code]-[Clamp style]
Example: NPCS-50-AL-SC → rib height 50mm, aluminum alloy, side clamp for trapezoidal sheet

  • Rib height codes: 35, 50, 65, 75
  • Material: AL (anodized) / GS (galvanized steel)
  • Style: SC (side clamp), MC (mid clamp), EC (end clamp)

Standard kit components

  • Upper clamp and lower clamp (matched pair)
  • M8x40 stainless steel bolt + nyloc nut
  • EPDM rubber pad (2mm thickness, pre-cut)
  • Flat washer and spring washer set
  • Installation torque wrench adapter (optional)

Packaging: 50 sets per carton + installation guide

* Load values based on static testing per UL 2703 and EN 1991. Field engineering recommended for snow/wind zone specific adjustments. All products meet RoHS requirements.