Praise for Polyfoam ECO Floorboard Following Passivhaus Specification

By Admin

Knauf Insulation

27th Jun 2016

Knauf Insulation Polyfoam ECO Floorboards specified for Passivhaus project

Knauf Insulation’s Polyfoam ® ECO Floorboard extruded polystyrene has been specified by a Midlands based architect for his own self-build Passivhaus project, which demanded very low U-values for his low energy building. With its outstanding thermal insulation performance, Polyfoam ECO Floorboard helped to meet the required U-value of 0.09W/m 2 K.

Jon Chadwick was part of the team responsible for designing the acclaimed Centre for Medicine at the University of Leicester – recognised as the UK’s single largest Passivhaus project – which was where he first specified Polyfoam ECO Floorboard.  

Jon said: “With its British Board of Agrèment (BBA) certificate I was reassured that Polyfoam ECO insulation had all the right accreditations and could provide sufficient compressive strength to carry the applied loads. These included not just the timber frame, but loads like the 1200 litre thermal store which will be fed by the solar panels and wood burning stove. In addition, Polyfoam ECO Floorboard has a certified BRE Green Guide rating of A and Environmental Product Declaration certificate – giving me the utmost confidence that the product provided a sustainable solution”

During the design stage Jon, called on the assistance of Knauf Insulation’s Technical Support Team (TST) to ensure the optimum grade and thickness of Polyfoam ECO Floorboard was selected, to support the design loads for the house and to achieve a U-value of 0.09W/m 2 K. TST responded by running the necessary calculations and recommending the use of Polyfoam ECO Floorboard – satisfying both the specialist consultants and local Building Control.

Polyfoam ECO Floorboard insulation in a thickness of 350mm was laid as a raft to carry the 120 square metre reinforced concrete slab. A further 200mm thickness of Polyfoam ECO insulation was installed vertically to act as a permanent shutter for the concrete pour.

As an extruded polystyrene insulation (XPS) material, Polyfoam ECO Floorboard is a robust and lightweight solution, ideal for situations where the insulation is subject to high compressive loads – such as this project.

The Shropshire self-build is a stand-out example of Knauf Insulation’s capacity to supply specifiers and contractors with product solutions, which offer exemplary quality and performance in meeting the most testing of technical challenges. It can be expected that many more projects will make use of Polyfoam ECO Floorboards as the popularity of the Passivhaus standard grows for creating highly energy efficient and sustainable properties. 

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Tags on this post: flooring, insulation