Metal Waterproofing
R-MER SEAM
R-MER Seam is a low profile standing seam metal roof system delivering streamlined aesthetics with concealed fasteners. Its 25mm low profile design and secret-fix, click-together installation deliver fast, weathertight performance on commercial and residential projects.
Fire resistance
BROOF(t4) classification · EN 13501-5.
Fire reaction
C-s2,d0 (HPS / Plastisol) or A2-s1,d0 (all other coatings) · EN 13501-1.
Material specification
0.50mm gauge · approximately 5.32 kg/m² as laid.
Why specify R-MER SEAM?
Secret fix installation
Hidden fixings create a clean standing seam appearance while eliminating visible penetrations through the external sheet.
Roof & wall applications
Suitable for both roof and wall installations, allowing a coordinated metal envelope across multiple building elements.
Low profile standing seam
The 25 mm profile delivers a contemporary standing seam appearance suited to modern architecture and sympathetic refurbishment projects.
Long panel lengths
Manufactured in 500 mm widths and lengths up to 13 m, with suitability for roof pitches from 4°, providing flexibility for a wide range of building designs.
System Components
R-MER SEAM comprises engineered steel panels, concealed fixing clips, and integrated breather membrane to deliver long-term weatherproof performance with minimal visual impact.
Steel Profiled Sheets
Pre-coated Steel Panels
Pre-coated steel panels with low profile standing seam for contemporary roof and wall applications.
- Material: 0.50mm steel with factory-applied coating
- Profile: 25mm low profile standing seam
- Width: 500mm
- Length: 1800mm to 13000mm (bespoke)
- Sealing: Butyl seals at sheet laps for watertight integrity
- Corrosion resistance: No site finishing required
Secret Fix Clips
No Penetration
Concealed clip system securing panels without surface penetration for clean aesthetics and weathertight performance.
- Fixing type: Secret fix (hidden fasteners)
- Attachment: Clips fix to substrate spacers
- Surface integrity: No penetration of weathering surface
- Panel alignment: Maintains positioning and seam integrity
- Water protection: Prevents potential ingress points
Breather Membrane
Protecting Substrate From Condensation
Vapour-permeable breather membrane protecting substrate from condensation while allowing moisture escape.
- Protection: Prevents interstitial condensation in roof assembly
- Permeability: Vapour-permeable (allows moisture escape)
- Safeguards: Structural deck and insulation layers from moisture
- Performance: Maintains thermal efficiency and structural integrity
Structural Substrate
Stable Fixing Surface for Secret Fix Clip Spacers
Plywood or OSB deck providing stable fixing surface for clip spacers and load transfer to building structure.
- Material: Plywood or OSB (Oriented Strand Board)
- Function: Stable fixing surface for secret fix clip spacers
- Support: Spans between structural purlins or rafters
- Load transfer: Transfers roof loads to building structure
- Stiffness requirement: Adequate to prevent panel deflection
- Performance: Maintains seam weathertightness
Quick Reference
| Specification | Details |
|---|---|
| System Type | Low profile standing seam with secret fix clips |
| Material | Pre-coated galvanized steel |
| Sheet Thickness | 0.50mm |
| Profile Height | 25mm |
| Panel Width | 300mm & 500mm |
| Panel Lengths | 1800mm to 12500mm (bespoke) |
| Standard Colours | arious colours in a choice of Colorcoat Prisma® and Colorcoat HPS200 Ultra® by Tata Steel and SSAB Greencoat® Pural. |
| Breather Membrane | Viking vapor-permeable membrane |
| Substrate | Plywood or OSB structural deck |
| Guarantee Period | Up to 20 years |
Need technical specification advice?
Your local Garland UK Technical Manager can advise on system selection, detailing, and project-specific requirements to help develop the appropriate R-MER specification.
Proven results
across every sector.
See how we’ve helped organisations maximise building performance, delivering reliable protection and long-term value.
