Too much carbon in the atmosphere contributes to global warming. Currently, the operation of buildings in the UK is estimated to contribute around 40% of the country’s greenhouse gas emissions. Performance improvements are required both for new build and for refurbishment works.
Notwithstanding a building’s performance, similar consideration must be given for infrastructure projects when developing designs such that operational carbon can be reduced as much as possible across the construction sector.
To drive this improvement, the UK Government introduced the Climate Change Act 2008, which committed to reducing the UK’s carbon emissions by 80% by 2050, from a 1990 baseline.
In terms of how this affected the construction sector, following on from the Climate Change Act, the UK Government’s Construction 2025 strategy, published in July 2013, set a target of a 50% reduction in greenhouse gas emissions in the built environment by 2025, again from a 1990 baseline.
This target was then tightened in 2019 when the UK Government signed the Paris Agreement in 2016 and became the first of the major economies to target net-zero carbon emissions by 2050. In terms of the built environment, the operational performance of carbon in new and refurbished or existing buildings requires serious planning and effort if they are to achieve the ambitious net-zero target.
Part L of the Building Regulations
Part L refers to documentation regarding the need to factor in the conservation of fuel and power when designing buildings. To comply with the Part L Building Regulations, the CO2 emissions from the building should be on or less than the target set out in the documents.
The UK Government’s strategy to meet the EU’s Energy Performance of Buildings Directive (EPBD) is the use of Energy Performance Certificates for all commercial and non-domestic buildings. Part L has seen several revisions as it seeks to comply with and implement the requirements of EPBD.
To calculate the emission rate of CO2, the annual energy requirements for space, heating and lighting are calculated, but renewable energies can offset these.
Non-domestic users (i.e., businesses) are now subject to paying the Climate Change Levy or the ‘carbon tax’, so it’s clear that the regulations covering design and construction activities are attempting to incentivise a drive to sustainable solutions to appeal to prospective investors and buyers.
BREEAM – How does this play in the situation?
In developing sustainable construction markets, three main aspects need to be considered:
However, there is no standard way to calculate this or a defined methodology, and so there are several tools on the market currently in use. For example, the Civil Engineering Environmental Quality Assessment and Award Scheme or CEEQUAL is an international sustainability assessment tool used for assessing sustainability in infrastructure projects.
Launched in 1990, another is the Building Research Establishment Environmental Assessment Method or BREEAM. In the UK BREEAM is the leading and most utilised tool in assessing sustainability and environmental performance in buildings. In 2015 BREEAM acquired CEEQUAL, thereby covering both the construction of buildings and infrastructure. It aims to set best practice standards for the environmental performance of buildings with a direct emphasis on design, specification, construction, and operation.
As an industry, whilst some clients may require a BREEAM rating, it is still not a legislative requirement to use BREEAM, albeit it is generally considered that obtaining a BREEAM rating is beneficial for the future residual value. Publicly funded projects that specifically reference the Government Construction Strategy require that an environmental assessment is carried out. Whilst not stating this must be BREEAM, it does state that “where BREEAM is used, all new projects are to achieve an excellent rating.”
BREEAM has issued 594,011 certificates and has 2.3m registered buildings, and is in use across 89 countries.
Different versions of BREEAM are available and are used to assess the sustainability performance of a project or building at various points in the project lifecycle, with different versions available for most buildings and locations, including new buildings, existing buildings, refurbishment projects and large developments. In summary, they are:
- BREEAM New Construction – Used for new, non-residential UK buildings.
- BREEAM In-Use – For existing buildings and aimed at reducing running costs and improving environmental performance. This includes non-domestic, commercial, industrial and retail buildings.
- BREEAM Communities – Used for master planning entire communities.
- BREEAM Refurbishment – Used for sustainable housing refurbishment projects.
- BREEAM International New Construction – used for new residential and non-residential buildings but internationally.
- BREEAM New Construction – Used for new build infrastructure assets.
In particular, the BREEAM UK New Construction introduced in 2018 recommends using a BREEAM Assessor as early as possible in the project development and lifecycle, e.g., RIBA Stage 1 – Preparation and Brief. The concept here is that once a design is developed and then scored, if changes are required to become more sustainable, this is inefficient. Therefore, to influence design solutions and generally steer a more sustainable design solution, the assessor should be involved from the outset.
BREEAM – How is it calculated?
The BREEAM Assessor will review the project data to evaluate the procurement, design, construction and operation of a development against the BREEAM range of benchmarks or matrix. It does this by reviewing the project across nine different categories, which are:
- Management – Overall policy, commissioning, site management and procedural issues.
- Health & Wellbeing – Internal or external issues that affect health, safety and wellbeing.
- Energy – Operational energy and CO2 issues
- Transport – Transport related CO2 and location related factors
- Water – Water efficiency and consumption
- Materials – What are the environmental implications of building materials, including lifecycle impacts.
- Land Use & Ecology – Greenfield and brownfield sites, ecological value conservation and enhancement of the site
- Pollution – Air and water pollution issues.
The incentivisation for the asset owner and developer behind each category is there are mandatory requirements which are needed for compliance and will need to be demonstrated to the BREEAM Assessor, but also the project can gain extra credits for going above and beyond compliance, thereby driving good performance which is recognised on a scalable certification award, i.e.,
- Very Good
One of the challenges of Part L of the Building Regulations is that whilst compliance at the design stage meets the regulations and therefore is acceptable. However, buildings generally do not perform as well in reality as they do in theoretical practice (design), and this difference is known as the performance gap. For example, findings from a review carried out on exemplar designs in the Buildings Services Journal found those studied had energy consumption twice as much as predicted in the design stage. Notwithstanding this, on average, energy consumption during occupation is ten times higher than envisaged at the design stage in average new builds.
Since 2008, to counter this, BREEAM has made it compulsory to undertake an assessment ‘Post Construction Review’ and to obtain a BREEAM certificate at this stage. This is to assess the building’s energy performance more accurately based on as-built information and a site inspection of the completed building.
But to also acknowledge the progress made earlier in the project lifecycle, and as noted above to encourage the early appointment of a BREEAM Assessor, there are two stages of assessment and certification, the completion of a design stage assessment and the issuance of an interim certificate.
So, what do you need to do to get an outstanding rating?
To get an outstanding score, the project needs to get a rating of 85% or above, which is not easily accomplished.
Whilst early engagement with an assessor to influence design development and drive best practice is certainly a step in the right direction, the following sort of ideas could then drive the award of further credits:
- Materials – The use of recycled aggregates in construction (concrete) as much as possible and innovative use and recycling of energy in the building, e.g., where something generates heat and uses that heat or energy to power another part of the building.
- Waste – The use of pre-cast materials to minimise wastage is another way to gain extra credit but go above and beyond the usage of pre-cast concrete panels, flooring etc. and seek to innovate the use of pre-cast materials where they are not already industry standard.
- Water – Efficient design in terms of sustainable water solutions, e.g., supply shut off in sanitary areas may seem standard, but what about leak detection, metering on all inlets to accurately determine and adjust water usage to drive building use efficiency.
- Health & Wellbeing – In terms of health and wellbeing, think of the usage of the building, i.e., if it is a city centre with limited parking by allowing for an increasing the number of cycle bays, it encourages the use of cycling.
- Materials – the use of floor and ceiling finishes in the show areas only of a building.
- Ecology – The use of a Biodiversity Champion to review, assist and influence site activities such that they can avoid detrimental impacts on-site biodiversity. The principal contractor on-site should also train the workforce on the ecological risks and actively manage them.
- Pollution – If there are refrigerants in use in the building, have them fitted with leak detectors which are capable of continuously monitoring.
- Management – Demonstrate that all third-party stakeholders have been consulted before the completion of the concept design. And that not only has consultation taken place, but you can demonstrate that in conjunction with those stakeholders you have considered: functionality, quality, impact, management and operational implications, impacts on the local community, inclusive and accessible design.
- Energy – For motorised walkways such as escalators, fit them with load sensing devices that directly affects the motor output link to demand for automated operation.
- Transport – Demonstrate how you have considered the travel patterns and opinions of the existing building or site users when developing your design and have made allowance for this. Be able to demonstrate that you have considered the impacts of disabled access requirements and public transport links that currently serve the site and how all of these requirements and needs will be managed and supported by the building’s management team once in operation.