Facade panels NPSP made from residues from sewage treatment

Climate-neutral and circular construction with facade panels made from wastewater treatment waste

In collaboration with NPSP Delft, Hoogheemraadschap De Stichtse Rijnlanden has developed facade panels made from wastewater treatment waste. Schoots Architects designed the panels, which must meet strict construction requirements. The facade of an HDSR business premises in De Meern will be the first to be clad with these innovative panels. This will make the building more sustainable and at the same time serve as a practical example to show market parties that circularity, sustainability and a technically advanced and stylish product can go well together.

Reusing toilet paper can make a significant difference in global CO2 emissions

Every year, we flush approximately 180,000 tons of toilet paper down the toilet in our country. This paper contains cellulose, a valuable, biological raw material. Cellulose is extracted from trees and plants and is the most important component of paper and cardboard. It is also used in construction, for example as insulation material.

Recovering cellulose from used (toilet) paper prevents the felling of additional trees, saves energy and reduces CO2 emissions. The 200m2 façade in De Meern requires sieved material from 2,000 rolls of toilet paper. This saves 10 tonnes (75%) of CO2 emissions compared to a brick façade. This equates to preserving 10 trees.

Nanda van Zoelen, water board member: “As a water sector, we are working together to extract more value from the water chain. For the water board, recovering valuable raw materials from wastewater is an important part of this.”

Important step towards climate-neutral and circular construction

The quality of our surface water is under pressure and, as a result of climate change, the risk of flooding on the one hand and water shortages on the other is increasing. HDSR strives to prevent negative climate impact in all its activities and, if possible, to convert it into a positive impact. Concrete objectives include: energy neutral in 2030, circular in 2050 and improvement of the quality of surface water. In addition to reusing residual materials and saving energy and CO2 emissions, the amount of residual materials discharged from sewage treatment plants into surface water is also reduced by recovering cellulose.

Sustainable and circular – from ‘waste’ to ‘source of energy and raw materials’

Sewage water is much more than just waste. It is the source of new products and raw materials. In addition to facade panels, cellulose can also be used as a binding agent in asphalt, for example, and the heat from the water can be used to heat buildings. We can recover the raw material Kaumera from the residual product of the treatment plant, the waste sludge. Kaumera can be used in agriculture and horticulture. Research is also currently underway into how Kaumera can be used as a fire retardant, for example in a next generation of facade cladding.

Innovative driver

With the recovered cellulose at the HDSR sewage treatment plant, NPSP Delft has developed a facade panel that is strong and dimensionally stable. The panel is resistant to UV radiation and other weather influences and has an expected lifespan of at least 50 years. The developed facade panels meet the quality requirements for fire safety. The design by Schoots Architects shows the aesthetic possibilities.

Nanda van Zoelen: “With the three parties, we have developed a sustainable, technically advanced construction product. We cordially invite project developers and construction companies to discuss with us how they can use this product.”