TS EN 13984

TS EN 13984 is a standard for flexible plastic and rubber sheets used as water vapour control layers in buildings, setting out their definitions, characteristics, and a framework for conformity assessment. In practical building-envelope terms, it addresses membrane products used to manage vapour flow and reduce the risk of condensation within roof, wall, and related assemblies.

Product type and functional role

In this technical field, a vapour control layer serves a different purpose from waterproofing. Its role is to limit vapour diffusion through a building assembly to a suitable degree, helping the structure perform as designed in service. The standard covers both reinforced and unreinforced products, an important distinction because reinforcement can influence handling, tensile behaviour, dimensional stability, and resistance to mechanical damage during installation.

Definitions, properties, and test basis

• The standard defines the product terminology and required characteristics for these sheets.
• It specifies test methods used to evaluate conformity with the requirements.
• Its scope covers flexible sheets made of plastic or rubber.
• The technical focus is the vapour-control performance of the building layer.
• Assessment is based on the referenced test standards linked to the product characteristics.

In general technical context, the performance of vapour control layers is associated with properties such as water vapour transmission behaviour, thickness, tensile response, tear resistance, and the reliability of joints and overlaps. The referenced test standards provide the means to measure these characteristics and compare them with declared values. Although this edition of TS EN 13984 has been withdrawn, it remains a useful reference for understanding how building-physics requirements are organised for multilayer envelope systems.