​ Innovative Construction Method for Stainless‑Steel Angle Lightning Receiving Tape on Stone Curtain‑Wall Roof

Innovative Construction Method for Stainless‑Steel Angle Lightning Receiving Tape on Stone Curtain‑Wall Roof

Drawbacks of traditional solutions

Conventional lightning protection adopts exposed galvanized round bars or stainless‑steel tubes with metal brackets. Exposed fittings deform easily; damaged zinc coatings cause rust stains on stone cladding. Protruding tapes hinder gondola cleaning work with safety risks and water‑leaking joints, ruining the architectural facade.

This improved technique originates from the ZA Jiancheng Center project in Hangzhou. 40×4 mm 304 stainless‑steel angles are applied as semi‑concealed edge‑wrapped lightning tapes, bonded with epoxy resin without external metal brackets. Approved by design institutes and lightning‑protection authorities, the system passes full acceptance for lightning protection, waterproofing and anti‑corrosion performance.

Core technical features

1. Optimized side‑flash protection: Tapes are mounted right at the outer edge of the facade, solving the long‑standing limitation of traditional exposed installation.

2. Reliable TIG welding: Mechanically beveled joints with double‑layer argon‑arc welding achieve sound fusion without splashing contamination on stone panels.

3. Slim integrated appearance: Semi‑recessed layout, 45‑degree mitered corners, pre‑fabricated semi‑circular expansion joints at building movement gaps. Tin coating is applied between dissimilar metals. Only a 4‑mm thin strip remains visible on the exterior wall.

4. Higher construction efficiency: Installation can be finished right after side stone panels are fixed. Bracket‑free bonding shortens cross‑working periods between curtain‑wall and electrical teams.

5. Durable waterproof design: 30‑mm‑thick stone forms a drip edge with 5‑mm angle overhang. Weather‑resistant structural sealant fully seals all joints. Stainless steel guarantees long‑term rust‑free performance.

6. Reduced high‑altitude risks: Pre‑assembly is completed on the roof ground. Only limited field joints remain, cutting gondola working hours and construction costs.

Critical operation procedures

Raw material inspection for 304 stainless‑steel angles and matching welding wires. Synthetic fiber slings are used during hoisting instead of carbon‑steel wire ropes. Pre‑fabricated segments are controlled within 18 m. Deburr and degrease weld zones before V‑groove TIG welding. 30×4 mm stainless‑steel flat bars serve as lap reinforcements with a lap length at least twice the strip width.

Clean and dry stone surfaces before epoxy bonding. Temporary fixtures hold angles until full resin curing. Sealant work at expansion gaps is finished after expansion‑joint welding. Tin coating prevents galvanic corrosion between galvanized down conductors and stainless‑steel tapes. Stainless lock washers and bolts ensure firm electrical connections. Welded galvanized areas are coated with two‑coat zinc‑rich epoxy primer plus top finish.

Earthing systems shall be constructed and resistance‑tested before lightning tape installation. The whole lightning loop is connected for final resistance measurement. Concealed inspection approval is mandatory prior to final stone closing and caulking.

Conclusion

This bracket‑free semi‑concealed bonded lightning‑tape technology delivers stable waterproof and anti‑corrosion performance, seamless facade aesthetics, safer site operation and higher productivity. The method provides valuable practical benefits for widespread promotion on modern public curtain‑wall buildings.