Building Sustainability into the Development Project Eden

Challenge

ECF has a vision for their 12 storey, 110,000ft² office building to increase local biodiversity and be as sustainable and energy and carbon efficient as possible.

Designed to be Net Zero Carbon in Operation, WELL enabled, BREEAM Outstanding and targeting a NABERS UK 5.5* rating, the development is also working towards an embodied carbon level of 750kg/CO₂/m² which is considerably lower than a standard building.

The project is driven by the need to reach high sustainability standards, which meant experience in the delivery of Net Zero Carbon buildings was essential for success. Bringing together a project team to meet the standards required in a cost-effective way was a key challenge throughout the design and build process. Adding further complexity, the building will be one of the first in the UK to have its operational performance verified using the NABERS UK scheme. The energy efficiency rating scheme is designed to help building owners target, measure and communicate their energy performance but finding contractors with the skillset and knowledge base to undertake the Design for Performance approach was difficult.

Solution

To meet all of their sustainability requirements, our client’s sustainability vision was embedded across the project team from the start. All requirements for operational energy, embodied carbon and biodiversity net gain were written into the building contract, which meant everyone worked in collaboration to achieve the project goals.

Contractors followed a clear methodology for measuring and reporting and certifying at completion. By working collaboratively, we were able to balance sustainability drivers, time and cost to deliver pragmatic solutions, manage risk and maintain excellent relationships on site.

Our sustainability solutions included:

• Glazing area limited to increase thermal properties of external façade
• Enhanced insulation values in line with passivhaus standard
• Air tightness rating of 2m³/hr/m² @ 50Pa compared with the Building regulation target of 10m³/hr/m² @ 50Pa
• Enhanced certification rates to provide free cooling
• Combustion free, all electrical building
• Air source heat pumps providing low carbon heating and cooling
• CO₂ heat pumps providing high efficiency low carbon hot water
• Wider heating and cooling setpoints to reduce energy whilst maintain comfort conditions
• Reduced internal heat gains and loads to improve equipment efficiencies
• Demand controlled ventilation linked to CO₂ sensors
• Early stage carbon analysis for structural options to choose optimised structural solution
• Recycled steel for reinforcement
• >50% cement replacement for concrete used in substructure, >30% cement replacement for concrete used in superstructure
• High recycled content material for façade and structure
• Exposed ceilings in office areas
• Recycled raised access floors
• Europe’s largest green wall – 355,000 plants