Copper Sheet and Strip for Building Construction

B370: Standard Specification for Copper Sheet and Strip for Building Construction

When specifying materials for critical building components like roofing, flashing, and drainage systems, engineers and architects demand reliability and proven performance. ASTM B370 provides the essential blueprint for ensuring that copper sheet and strip meet stringent quality standards for these applications, offering a foundation for durable and aesthetically pleasing construction.

What is B370?

ASTM B370, "Standard Specification for Copper Sheet and Strip for Building Construction," is an authoritative standard that defines the material properties, dimensions, and quality requirements for copper used in architectural applications. Developed by ASTM International, this comprehensive specification ensures that copper sheet and strip are manufactured to consistent, reliable specifications suitable for the demanding environment of building construction.

Scope & Purpose

This standard governs the production and quality of rolled copper sheet and strip intended for flat lengths or coils. Its primary applications include roofing systems, flashing, gutters, downspouts, and general sheet metal fabrication within buildings. Crucially, B370 explicitly excludes copper intended for electrical applications, focusing solely on its use as a durable construction material.

Who Must Comply?

• • Primary Audience: Architects, structural engineers, materials engineers, sheet metal contractors, and building inspectors.
• • Industries Affected: Construction, architecture, and metal manufacturing industries.
• • Compliance Nature: While often specified voluntarily by designers and engineers, compliance is effectively mandatory when B370 is referenced in project specifications and contracts.
• • Enforcement: Compliance is typically verified through material testing, mill certifications, and site inspections by project engineers, architects, or designated third-party inspectors.

Key Requirements Overview

The standard requires that copper sheet and strip conform to defined chemical composition limits, ensuring a high percentage of copper for optimal performance and longevity. Professionals must ensure that the material is manufactured to specified tempers, offering a range of hardness and strength characteristics suitable for various fabrication and installation needs. Key provisions include strict adherence to dimensional tolerances for thickness, width, and length, which are critical for proper fit and weatherproofing. The specification also mandates quality control measures for workmanship and finish, ensuring aesthetic appeal and preventing defects that could compromise performance.

Related Standards & References

ASTM B370 works in conjunction with other ASTM standards to provide a complete framework for copper use in construction. Specification B101 is a complementary standard that addresses lead-coated copper sheets and strip for building construction, offering an alternative for specific moisture or corrosion resistance needs. Furthermore, Specification B248 ("General Requirements for Wrought Copper and Copper-Alloy Plate, Sheet, Strip, and Rolled Bar") provides overarching requirements that often apply to materials produced under B370, covering aspects like workmanship and testing methods.