Reaching net zero carbon targets in the built environment

Momentum for sustainable buildings is growing as the sector needs to prepare for the whole net zero carbon approach of the future, when it will become ‘the norm’.

Apartment lounge working to a net zero carbon, sustainable building - Manor Interiors | BTR News

By Farhan Malik, CEO, Manor Interiors

The momentum for sustainable buildings is growing. Corporate EGS drivers, an increased interest from residents, and the UK Government’s 2050 net zero carbon targets – passed in law on 27 June 2019 – are all drivers in making this a priority.

Existing buildings currently contribute 40% of the total carbon emissions each year in the UK. In 30 years’ time, most buildings that will exist have already been built – so the transition will involve renovations and refurbishments. Although the scale of changes required are challenging, net zero carbon buildings will need to become ‘the norm’.

The UK Green Building Council (UKGBC) is leading the way in helping to support the built environment in the transition to net zero carbon. Its Advancing Net Zero programme is supporting the sector to deliver the emissions reductions that’s needed to meet the Government’s targets – but cost implications are a top concern for many.

The cost implications of net zero carbon buildings

The UKGBC conducted a feasibility study which looked at the design, delivery and cost implications of net zero carbon buildings. The report provides an evidence base for key design changes and how they will effect costs.

The study looked at the cost implications of two existing buildings – a residential and office building. Design iterations were carried out – looking at meeting net zero carbon by 2025 and 2030. For the residential building to meet 2025 targets, the design was changed by replacing gas boilers with air source heat pumps, replacing the concrete structure with timber frame, and the reduction of glazing areas. The office building design was changed by replacing a steel and concrete structure with hybrid steel and cross-laminated timber in the superstructure, introducing a mixed mode ventilation, and the dematerialisation of fitout and removal of the server room.

The cost implications where lower if 2025 targets were met, compared to 2030. There was an uplift in costs of 3.5% for the residential building and 6.2% for the office building for 2025 targets. These costs are likely to be recouped through a reduction in operational costs and capital and rental value. For 2030 targets, the uplift was higher – at 5.3% for the residential and between 8% to 17% for the office building.

The net zero carbon roadmap

The transition to a net zero carbon future for the built environment starts with encouraging action today. The roadmap ahead will lead to tighter requirements before we reach the point of a whole life carbon approach.

There are some solutions that support measuring building emissions – with technology and the IoT solutions that some Build to Rent operators have incorporated. Moda Living, for example, has a complete digital infrastructure which uses a combination of technologies. This smart building technology allows them to measure energy performance, and sensors will automatically adjust lighting and air-conditioning – reducing energy costs.

Another Build to Rent developer has recently adopted a net zero carbon approach in its plans for a new Build to Rent scheme in Birmingham. Architectural practice, Associated Architects will start with fabric first and Passivhaus principles, with designs created to meet energy performance targets. The plans look at a whole building approach to achieve deep energy efficiency – which will incorporate smart controls, triple glazing and super insulated walls amongst other Passivhaus principles.

The drive to meet net zero carbon targets will continue as the sector educates itself and more case studies appear. The roadmap to the transition has started, and the sector again will need to work together for a better built environment.