Using FF-EPS insulation as thermal insulation for exterior walls

The FF-EPS 60 S thermal insulation for walls is highly cost effective and safe in terms of moisture performance, with a declared thermal conductivity λD of 0.031 W/mK. FF-EPS insulation products are suitable for new construction, low-energy, passive, and zero-energy construction, as well as for supplementary thermal insulation for older buildings.

FF-EPS 60 S insulation products can be used with various framework materials. The frames can consist of wood, steel, concrete, precast concrete, brick, lightweight concrete (Siporex) or breeze block. Structures that are thermally insulated with FF-EPS usually require a separate air or vapor barrier layer, as the product does not have a high enough water vapor resistance to function as vapor barrier on its own. We recommend using elastic PU foam sealant for the seams and joints between panels.

FF-EPS insulation products are suitable for all wall structures

As a framework material for an exterior wall, rock (concrete, brick, breeze block) provides an excellent base for FF-EPS. The exterior surface of the FF-EPS 60 S panels can be clad with wood facing or plaster may be applied directly on to the surface of an aged panel. The FF-EPS insulation panels with locking tongue and groove are installed on the outside of the framework as a continuous layer of insulation by, for example, bonding the panels with mortar or attaching them with a PU foam adhesive to a supporting wall, securing the attachment with a few mechanical anchors. A concrete wall that is thermally insulated with FF-EPS insulation does not require an additional vapor barrier. The thickness of insulation is determined according to the desired U value. For example, a U value of 0.17 can be achieved with an FF-EPS insulation of 180 mm. To approach passive levels, the U value of a wall should be at least 0.12, in which case the required insulation thickness is 250 mm.

The framework of the exterior wall may also be constructed from wood, in which case the structure can be built as follows: Finnfoam or FF-PIR thermal insulation panels are installed on the interior surface of studs or between them, which also function as vapor barrier within the structure. A continuous layer of FF-EPS panels is installed on the exterior of the framework. The thermal conductivity of the layer of FF-EPS panels on the outside of a load-bearing framework must be as high or higher as that of the Finnfoam or FF-PIR insulation in between the framework elements to insure proper moisture performance. The thickness of insulation is determined according to the desired U value. With a timber frame, the exterior face is constructed as a ventilated structure.