ISO/TC 163/SC 3/WG 9 - Exterior insulation and finish systems

This document specifies the design requirements, selection and application of exterior insulation and finish systems (EIFS) for use by building designers, building code officials, product manufacturers and contractors in order to sustain the installed performance and durability of EIFS. NOTE This document does not address all aspects related to EIFS design, selection and use. A working knowledge of applicable regional building codes and regulations is helpful when working with this document. There could be other considerations for specific installations that are not addressed by this document. This document contains design requirements for the design and installation of an EIFS as a wall cladding system. The document includes selection of materials that meet the requirements of ISO 17738‑1, and installation requirements in accordance with ISO 17738‑2 and covers the interfaces between EIFS and other building assemblies and components. This document refers to adhesively fastened systems, although mechanical fastening could be required in specific circumstances (refer to Annex A). For information on EIFS resiliency, refer to Annex B. This document does not specify the structural design of the substrate to which the EIFS is attached, nor does it provide design requirements when the installation of EIFS uses mechanical fasteners. This document is applicable to new and retrofit EIFS installations.

This document specifies requirements for the installation of exterior insulation and finish systems (EIFS) for wall applications using material which meet the materials requirements of ISO 17738‑1 and the design requirements of ISO 17738‑3. This document further includes installation requirements for the EIFS materials that include a water resistive barrier (WRB) and decorative projections as part of the cladding system for walls. This document does not include requirements for the structural design of the substrate/building structural members or for the integrity of the substrate/building structural members to which the EIFS is to be attached, nor the requirements for installation or repair of the substrate/building structural members before installation commences. This document does not include requirements for the competence that an EIFS installer needs for installation of the system. The installation of EIFS on horizontal surfaces exposed to direct precipitation is outside the scope of this document.

ISO 17738-1:2017 outlines requirements for exterior insulation and finish systems (EIFS), used in combination with a drained air space as an exterior wall cladding system. It also outlines the requirements for water resistive barrier systems that are to be used with EIFS. The EIFS wall cladding system is comprised of liquid-applied water resistive barrier, an adhesive for attachment of the thermal insulation boards to the substrate, rigid thermal insulation boards, a glass fibre reinforcing mesh embedded in a base coat on the face of the thermal insulation boards and a finish coat. The use of mechanical fasteners is outside the scope of this document, but is acceptable as a complement and/or as an alternate to adhesive for attachment where the substrate will not support adhesive attachment of the EIFS. In EIFS, the thermal insulation boards support the base coat with integral glass fibre reinforcing mesh. Systems where the reinforcement is the supporting element of the rendering, e.g. conventional stucco, are not covered by this document. ISO 17738-1:2017 does not purport to address all the health and safety aspects associated with its use. Anyone using this document has the responsibility to consult the appropriate authorities and to establish health and safety practices, in conjunction with any existing applicable regulatory requirements, prior to its use.