Low carbon insulation glass for Pearl in the Polder

In Stolwijk, De Vries en Verburg is putting the finishing touches to a sustainable and circular masterpiece: Pearl in the Polder. The contractor's existing headquarters is being expanded with meeting rooms, workplaces, a work café and a work studio, where sustainability, innovation and aesthetics go hand in hand. The ambitions for the project are high, with BREEAM-NL 2020 'Outstanding', WELL v2 Platinum, Paris Proof (Whole Life Carbon <200 kg CO2/m2) and an MPG ambition that is 60% more ambitious than the Building Code requires. Vandaglas' IsoPerform LCG XTR70/33 ORAE insulation glass fits this very nicely and guarantees excellent thermal performance, high energy efficiency and a comfortable indoor climate. Thanks to a high level of recycled glass, the ecological footprint of the insulating glass is also significantly reduced.

The floor plan of Pearl in the Polder is a triangle, subtly referring to the three core values "Reliable, Involved and Driven. The construction of the building consists of laminated beams and columns topped with CLT floor elements. Thanks to no less than 800 m2 of floor-to-ceiling insulating glass in the facade, the building offers a magnificent view of Stolwijk and the surrounding polder. 

Optimal light entry, maximum shading

Vandaglas was involved at an early stage by facade builder Wijnveen Aluminiumbouw BV, with whom De Vries en Verburg regularly carries out projects. "As Wijnveen's house supplier and in a triangle with the facade builder and contractor, we investigated the opportunities for this project," says René Goossen, Key Account Manager at Vandaglas. "An important desire was to allow maximum daylight in. But also to ensure good shading. Therefore, glazing with the solar control low-e coating XTR70/33 was chosen, which is characterized by a very high daylight transmission of TL 70% and an excellent solar factor of g 0.33. With this, the glazing reflects as much as 67% of solar heat, ensuring a pleasant indoor climate in all seasons."

Low carbon float glass 

The XTR70/33 coating garners high praise among architects, says Goossen. "The outer light reflection of the glass is 11%, which means the glass has the same light reflection as standard HR++ glass. Aesthetically, the glass is very neutral, while at the same time users benefit from unique technical properties. Besides this aspect, decisive for De Vries en Verburg was that it is a Low Carbon insulation glass: IsoPerform LCG XTR70/33 ORAE. A high-performance glazing that contributes significantly to the very ambitious sustainability performance of its new building." For Vandaglas, Pearl in the Polder was the first project for which it produced insulating glass composed of Low Carbon float glass. 

ORAÉ® is the first Low Carbon base float glass on the Dutch market and is produced by Saint-Gobain. "The production of ORAÉ® has the lowest carbon footprint in the world, with 6.64 kg CO2 eq. per m² at a glass thickness of 4 mm," explains Reinout Jansonius, CSR Manager at Vandaglas. "This means a reduction of 42% compared to the European baseline. By comparison, a standard float glass panel in the same thickness (4 mm) has a footprint of 11 kg/CO2 eq. per m2. Instead of sand, a remarkably high amount of recycled glass cullet (64%) is added in the melting process. This allows significant savings on virgin raw materials. Because the melting point of the glass is lowered considerably, enormous energy savings are made. Of course without sacrificing technical, qualitative or aesthetic performance."

National Environmental Database

The environmental burden of all materials used in Pearl in the Polder has been critically assessed. And the balance between the environmental burden during production and the use of the material in question was also carefully calculated, Goossen knows. "Because our IsoPerform LCG ORAE Low Carbon double insulation glass, as well as our TriplePerform LCG ORAE Low Carbon three-leaf insulation glass with a Category 1 (branded) product card is included in the National Environmental Database (NMD), De Vries en Verburg is assured of a very low Environmental Cost Indicator (MKI). The MKI of both products turned out to be even lower than expected. Whereas the average MKI in our industry is € 8.85, TriplePerform sits at an MKI of € 4.53 and IsoPerform at an MKI of even € 3.50 with a 30-year life span."

GlassAward 2025

"Thanks to the application of 800 m2 of thermally insulating and solar heat-resistant IsoPerform LCG XTR70/33 ORAE, Parel in de Polder saves as much as 33% on its CO2 emissions," Goossen emphasizes. "Not for nothing are we nominated with this project for the GlasAward 2025 of Bouwend Nederland Vakgroep GLAS." The award ceremony will take place during the BouwBeurs, on February 6 in the Auditorium of the Jaarbeurs Utrecht.