Circular House – A model for circular design

From the outset, our task was clear: supply the Circular House with more sustainable material solutions that meet the highest performance standards – yet use much less fossil based raw material and embody the circular economy.

Together with Recticel and Brightlands, we set out to help transform a highly visible demonstration building into a model for circular construction, proving that more sustainable PU foam is ready for real-world projects, not just theory.

Buildings account for roughly 37 % of global greenhouse-gas emissions³, with a quarter of those tied to the materials used before occupancy. Traditional PU insulation plays a key role during use-phase but still relies on fossil fuels as a primary source for raw materials. The team had to tackle two sides of the equation: maintain top-tier thermal and mechanical performance while achieving reduction in embodied carbon emissions — and do this in a building meant to stand for future-proof long-term sustainability.

We supplied our climate-neutral⁴ raw material Desmodur® CQ MS – with 25 % bio-circular attributed certified feedstocks via the mass balance approach – for use in Recticel’s Eurothane® Silver Impact insulation boards, enabling a CO₂ reduction of around 43%⁵ compared with conventional boards – all while preserving the high insulation performance builders’ demand.The Eurothane® Silver Impact insulation boards were installed by roofing specialist ZND Nedicom, demonstrating how lower-emission insulation solutions can be successfully implemented in real construction projects while maintaining the high performance standards. The result: the contribution to a building that meets the BREEAM Excellent sustainability standard. This project demonstrates how embodied carbon reduction and energy efficiency can work hand in hand to lower environmental impacts. ¹BREEAM stands for Building Research Establishment Environmental Assessment Method. The certification level “Excellent” is awarded to projects that achieve 70 % or more of the available assessment score. ²Low-carbon emissions refers to materials or processes that result in significantly reduced life-cycle greenhouse gas emissions relative to the market average for comparable products, based on verifiable LCA data. For this specific application, Recticel's Impact Insulation boards demonstrate a 43% decrease in life-cycle greenhouse gas emissions when compared to Recticel's standard insulation boards, as validated by their internal Life Cycle Assessment. ³UN Environment Programme, https://www.unep.org/resources/report/building-materials-and-climate-constructing-new-future (opens in a new tab) ⁴Climate neutrality is the result of an internal assessment based on the TÜV reviewed EcoPAss LCA method (ID No. 0000083440), of a partial product life cycle from raw material extraction (cradle) to the factory gate (of Covestro), also known as cradle-to-gate assessment. The calculation takes into account biogenic carbon sequestration based on preliminary data from the supply chain. No compensation measures were applied. ⁵Recticel’s LCA calculation according to EN15804+A2 standard, for modules A1 - A3 (cradle to gate), based on the mass balance method.