10 Top Tips for Targeting Net Zero Carbon

Even if you're not sure that your organisation or client is taking any active steps to lower the carbon emissions of their buildings, start the conversation about the climate and biodiversity emergency, net zero carbon and the future. If you are a building owner or occupant, then please find out more (you are in the right place!). Net Zero Carbon discussions can spark ideas and inspiration in design teams and help spread interest and understanding throughout industry and the wider public.

The most powerful decisions affecting the success and cost of your net zero carbon or low energy project are made right at the beginning of the briefing process. Setting the tone of the project and embedding low energy and net zero carbon in the brief from the outset will ensure designers give it adequate weighting when considering competing design decisions. Early decisions over how much building you need to build or how the building will be arranged on site (and whether its “form factor”, the heat loss surface area to floor area, is optimised!) will have a huge influence on the final energy consumption of the building. Early decisions to make efficiencies in the building form will also help optimise for cost!

Adopting low energy design strategies do not necessarily guarantee low energy buildings, the performance gap between how a building should perform and how it performs at practical completion can often be significant. Passivhaus design and certification brings a strict QA framework to the design and construction process. The Passivhaus standard has been proven to deliver completed buildings whose performance matches an expectation of ultra-low energy consumption. If you are uncertain whether or not to include Passivhaus in your building’s design brief, why not start the process with it in and take it out at a later stage if you must, as by then some of the benefits such as efficient form factor, appropriate glazing areas and potential for robust air-tightness and insulation detailing will be “baked in” to the design.

The production of construction materials accounts for 28% of the total global greenhouse gas emissions from the construction sector. Concrete and cement production alone contribute 8% of these emissions. Not considering the climate impact of our material choices or our decision to build new buildings will mean that our decisions only ever consider part of the picture. Even good intentioned actions could contribute to climate negative outcomes. To achieve net zero carbon, we need to lower the embodied carbon associated with the materials used in the built environment and look to offset or otherwise mitigate unavoidable emissions.

This closely follows on from tip no. 4. As a significant proportion of the carbon emissions associated with buildings arise as a result of the construction process itself, extending the lifespan of a sound existing building can be a lower carbon pathway than demolishing and building new. Retrofit involves the installation of an element or technology into a building which wasn’t there previously. It’s commonly used to describe an upgrading of elements within a building, such as thermal insulation or replacement of the heating system technology to improve efficiency and reduce carbon emissions.

Embed low energy design and the delivery of low energy buildings in the procurement process. Ensure that a low energy and net zero carbon brief is championed by key figures in the project from conception through the design stages and into the construction phase with the contractor and finally the FM team. On suitable projects, consider make achieving an A-rated DEC (display energy certificate) rather than an EPC a contract requirement.

Make sure your building operates energy efficiently and as designed by engaging in soft landings and aftercare. Ensure the people who will run or occupy the building are stakeholders during the design development and are briefed by the project’s designers so that they thoroughly understand how to operate the building in the most energy efficient way possible. Soft Landings, good graphical user guidance and staff/occupant training all can help. Set up an organised process of regular building performance reviews to ensure that both the technical and managerial aspects of how the building operates are optimised.

Reduce your energy loads as much as possible from the very start. This will make it easier to find highly efficient equipment to deliver the remaining loads within acoustic, physical, and financial restrictions, as well as keeping your future energy bills lower. It will also minimise any carbon offsets or energy generation you'll need to achieve to balance your energy emission budget. Reduce your energy demand as much as possible by firstly using passive measures, secondly efficient systems and lastly renewables.

The Energy Performance Certificates (EPC) produced for a building to show compliance with regulations or to provide an energy rating for a building at point of sale only report part of the energy picture. The real energy consumption of a building measured at its energy meters and sometimes reported on a Display Energy Certificate (DEC) is most important! It is the actual energy consumption of a building that allows its contribution to climate change to be measured. Systems such as Access Control (using permanently powered magnetic locks), Computing, AV equipment and fitted appliances are all examples of unreported energy consumption in the buildings EPC. Occupant behaviour can also make a huge impact on actual building energy consumption.

For buildings, carbon offsetting is a short-term fix, not a long-term solution. There is no substitute for reducing your own emissions in a way that you can verify, and carbon offsetting should always be the last resort. However, a net zero future needs more renewable energy generators, it needs more forest to absorb existing carbon dioxide and it also needs to protect and rejuvenate biodiversity. It therefore seems reasonable to us (whilst acknowledging their inherent risks of failure) to make use of carbon offset schemes in conjunction with a plan to improve one’s own buildings.