EN 1850-1:1999

Overview

EN 1850-1:1999 - Flexible sheets for waterproofing - Determination of visible defects - Part 1: Bitumen sheets for roof waterproofing is a CEN (European) standard that defines how to determine and assess visible surface defects in bitumen roofing sheets. Its scope focuses on identifying defects that could influence the functional behaviour of bitumen membranes used for roof waterproofing. The standard has been adopted nationally (example: SIST EN 1850-1:2000).

Key Topics

• Purpose: Establishes a common basis for visual inspection of bitumen waterproofing sheets to identify defects that may affect performance.
• Defect identification: Covers visible defects (surface blemishes, irregularities, discontinuities) that are relevant to the sheet’s functional behaviour.
• Assessment principles: Emphasizes evaluation criteria and judgement of whether defects are likely to impair waterproofing function or long-term durability.
• Quality control: Supports routine factory inspection and final product acceptance based on agreed visual criteria.
• Documentation: Encourages standardised reporting of findings to facilitate communication between manufacturers, clients and regulatory bodies.

Note: EN 1850-1 specifies the approach to determining visible defects rather than prescribing detailed manufacturing parameters or specific numerical acceptance limits. It should be used together with product performance and test standards for a complete quality assessment.

Applications

• Manufacturers: Use the standard to set in-house visual inspection procedures and ensure consistent product quality for bitumen roofing sheets.
• Quality control labs: Apply the standard when performing incoming or outgoing inspections and preparing inspection reports.
• Specifiers and architects: Reference the standard to define acceptance criteria in procurement documents and contracts for roofing materials.
• Contractors and installers: Use it as a basis for inspecting delivered rolls on site and for documenting visible defects before installation.
• Certification bodies and regulatory authorities: Use the standard as part of conformity assessment, registration and market surveillance for waterproofing products.

Related Standards

• EN 1850-1 is part of the CEN framework for flexible sheets for waterproofing. It is commonly used alongside other CEN product and test standards covering:
  • performance testing of bitumen membranes
  • installation and workmanship standards for roof waterproofing
  • national adoptions (e.g., SIST EN 1850-1:2000)

Using EN 1850-1:1999 as part of a wider quality and compliance program helps ensure bitumen roofing sheets meet expected visual and functional quality, reducing the risk of premature failure and warranty disputes.

Keywords: EN 1850-1:1999, bitumen sheets, roof waterproofing, visible defects, flexible sheets for waterproofing, CEN, quality control, visual inspection.