PIR boards for external wall insulation systems (ETICS)
Deep window reveals, narrow passages and projecting façade features can complicate an energy retrofit. PIR boards intended for external thermal insulation composite systems (ETICS) can improve wall insulation with a smaller increase in wall thickness than many conventional insulation materials. Suitability for a rendered finish depends on both the insulating core and the board facing. This can be useful where façade geometry and appearance matter.
1 A slim façade with effective insulation
The low thermal conductivity of PIR allows a thinner layer for a given thermal resistance. This can preserve the proportions of windows, limit the depth of reveals and simplify junctions with balconies, entrance canopies or existing window frames. EPS with a higher thermal conductivity needs a thicker layer for the same resistance. The difference matters on tightly spaced buildings and on older houses whose details might be obscured by a thicker façade.
2 A facing designed for the render system
PIR boards intended for ETICS differ from boards designed for other finishes. A suitable facing, such as a specially prepared glass fleece, provides the substrate for the layers specified in the system. This allows a rendered façade without exposed sheet-metal cladding or panels. Board, adhesive, reinforced base coat and finish must be compatible. Their combination determines how the finish performs and allows a traditional façade appearance with high thermal resistance for the depth of insulation used.
3 Let the building details guide the choice
Rigid boards make it easier to set out the insulation around openings and across large wall surfaces. In refurbishment work, an extra centimetre can mean altering flashings or narrowing a passage. An insulation material offering greater thermal resistance per unit thickness can help retain the existing detail, especially at narrow reveals and balcony doors. These lightweight boards can be rendered to preserve the character of the building. PIR is combustible. Check the required fire performance for the complete compatible ETICS. The principal benefit here is a slim, thermally effective façade where a thicker build-up would complicate the junctions.
SteelProfil helps select PIR boards for compatible ETICS. Our wider range includes first- and second-grade materials and items available from stock. Ask about current promotions and prices when planning the façade and the overall cost of the refurbishment.
