ISO 17738-2:2019

Overview

ISO 17738-2:2019 - Thermal insulation products - Exterior insulation and finish systems (EIFS) - Part 2: Installation - sets out minimum installation requirements for EIFS wall claddings. It applies where materials meet ISO 17738‑1 (materials) and designs follow ISO 17738‑3 (design). The standard covers installation of systems that include a water resistive barrier (WRB), thermal insulation boards, base coat, glass fibre reinforcing mesh, and finish materials, including decorative projections. It does not cover structural design of substrates, installer competence, or EIFS on horizontal surfaces exposed to direct precipitation.

Key technical topics and requirements

• Manufacturer single-source requirement: All EIFS materials and components for a project shall be obtained from a single EIFS manufacturer and installed per the manufacturer’s instructions kept on site.
• WRB and transition membranes: Installation requirements for liquid-applied WRB systems, transition membranes at joints/openings, and flashing to direct water to the exterior.
• Thermal insulation boards: Storage, handling, attachment, spacing/clearances, rasping/surface preparation, and aesthetic reveals (grooves) for insulation boards.
• Base coat and mesh: Attachment and encapsulation of glass fibre reinforcing mesh, terminations, wraps (back-wrap, pre-wrap, edge-wrap), and base coat surface requirements.
• Finish material: Execution and installation requirements for EIFS finish coats.
• Materials storage and handling: Labelling, protection from moisture, UV and extremes of temperature; liquid materials should be kept between 4 °C and 65 °C; insulation boards stored flat and covered.
• Substrate preparation: Substrate must be firm, sound and free of contaminants; new concrete/masonry generally allowed to cure 28 days before EIFS application.
• Environmental limits and protection: Typical installation temperature window 4 °C to 40 °C; when protection (tents, heat) is used it must be in place 24 h before, during, and 24 h after installation. Continuous service temperature limit +75 °C.
• Quality assurance: Annex B describes a Site Quality Assurance Programme (SQAP); Annex A addresses mechanical fasteners.

Practical applications and users

• Target users: EIFS contractors, façade installers, architects, specifiers, building envelope consultants, and manufacturers who need prescriptive installation requirements for EIFS wall systems.
• Practical uses: Preparing contract specifications, job-site installation checklists, QA/QC procedures, substrate acceptance criteria, and installer reference for WRB, insulation board handling, mesh embedding, and finish execution.

Related standards

• ISO 17738-1 - Materials and systems (materials requirements)
• ISO 17738-3 - Design requirements
• Other referenced standards: ISO 7345, ISO 9229, ISO 4624, ISO 8873 series.

Keywords: ISO 17738-2:2019, EIFS installation, exterior insulation and finish systems, WRB, thermal insulation boards, glass fibre reinforcing mesh, site quality assurance.