SIST EN 12691:2018

Overview

SIST EN 12691:2018 is a European Standard developed by CEN that defines a standardized test method for determining the resistance to impact of flexible sheets used for waterproofing roofs. It applies to bitumen, plastic, and rubber sheets designed specifically for roof waterproofing but can also be used for other waterproofing applications. The standard addresses the mechanical stresses these sheets endure, particularly focusing on dynamic short-term loads that may cause puncture through impact.

The test simulates real-life conditions where roofing membranes face impacts such as hail, tools, or debris during construction and in service. It ensures that the waterproofing materials can maintain integrity against puncture, helping manufacturers, testers, and specifiers guarantee product reliability and durability.

Key Topics

• Test Scope
  SIST EN 12691:2018 targets the determination of puncture resistance by impact on flexible waterproofing sheets. It covers dynamic loading conditions but excludes long-term static loads.

• Test Principles
  Impact testing is performed by dropping a fixed-weight steel mass with a spherical puncturing tool from a specified height onto the sheet sample. The specimen rests on either a hard support (aluminium plate) or a soft support (standard expanded polystyrene panel). Post-impact, the sheet is inspected for leakage indicating puncture.

• Apparatus and Setup

  • Drop mass: 500 ± 5 g with a specially hardened and shaped steel puncturing tool.
  • Support methods:
    • Method A (hard): Aluminium plate EN AW-6082, 300mm × 300mm × 3mm.
    • Method B (soft): Expanded polystyrene panel, 300mm × 300mm × 50mm, with controlled compressive properties.
  • Ballast ring and counter mass ensure consistent pressure and prevent movement during testing.
  • Release mechanism allows variable drop heights (200 mm to 2,000 mm) to simulate different energy impacts.

• Sampling and Specimen Preparation
  Samples are taken across the roofing sheet roll, cleaned, and conditioned for at least 24 hours at standardized temperature and humidity. Test specimens measure at least 150 mm × 150 mm and exclude edges.

• Impact Testing Procedure
  Impact is performed with one strike per specimen at the center, with five specimens tested per batch. The impact height is adjusted to find the maximum without causing more than one puncture in five tests. Leakage detection is carried out using a vacuum or pressure device with soap solution.

• Results and Reporting
  Resistance is reported as the maximum drop height (in mm) at which puncture does not occur in at least four out of five specimens. The test method used (A or B) must be indicated in the report along with detailed sample and procedure information.

Applications

• Roof Waterproofing Quality Control
  SIST EN 12691:2018 is used by manufacturers and testing laboratories to verify the quality and robustness of roofing waterproofing sheets before market release.

• Product Certification
  Compliance with this standard helps roofing materials achieve national and European certifications ensuring market acceptance.

• Material Selection and Specification
  Architects, engineers, and contractors reference this standard to select roofing membranes with proven impact resistance suitable for local weather conditions and project requirements.

• Research and Development
  Material developers use the test to compare formulations and improvements in bitumen, plastic, and rubber sheet products.

• Other Waterproofing Systems
  While focused on roof waterproofing, the methods may be adapted to test flexible sheets used in other waterproofing applications requiring impact resistance.

Related Standards

• EN 573-3: Defines chemical composition and forms of wrought aluminium alloys used for the aluminium plate in Method A support.
• EN 826: Specifies compression behavior tests for thermal insulating products like expanded polystyrene panels used in Method B support.
• EN 13163: Details specifications for factory-made expanded polystyrene thermal insulation products, relevant for the soft support panel in Method B.
• EN 13416: Provides rules for sampling flexible sheets for waterproofing to ensure representative test specimens.
• Standards on bitumen, plastic, and rubber sheets “Definitions and characteristics” complement EN 12691 by establishing classification and performance criteria for these materials.

Keywords: EN 12691, roof waterproofing, bitumen sheets, plastic sheets, rubber sheets, impact resistance test, puncture resistance, European Standard, flexible waterproofing membranes, roofing materials testing, CEN standards