Arun Energy have earned an excellent reputation for energy assessments throughout Scotland since 1994. Our clients include architects, builders, businesses, housing associations, local authorities, social landlords, as well as home owners and self-builders.
We pride ourselves in being solution focussed rather than mere ‘data loggers’, and are happy to use our expertise to find optimal solutions as appropriate to meet client requirements.
We have seen energy assessment develop from humble beginnings as a ‘niche’ service, into a fundamental part of current legislation relating to energy efficiency in buildings. It has become far more sophisticated over time, and this evolution continues.
Evolution of Energy Ratings in Scotland
The pioneering energy assessments were made under the National Home Energy Rating Scheme (NHER), which had been introduced in 1991. SAP was initially introduced in a basic form in 1995, but many organisations continued to use the then more advanced NHER ratings.
The majority of energy ratings were carried out on behalf of social landlords looking to improve their housing stock and reduce fuel poverty. There was no requirement for energy ratings in the Scottish building standards. Insulation requirements were minimal, single glazing was acceptable and extensions could be built without any wall or floor insulation.
In 1997 SAP rating based on energy costs was added to building standards as an optional method of compliance.
The 2002 regulations introduced a new SAP calculation using estimates of carbon emissions for compliance rather than energy cost.
2005 saw Building Regulations re-organised by the introduction of separate domestic and non- domestic handbooks, but otherwise the content changes were minimal.
The 2007 amendments to the regulations saw other options to compliance withdrawn, resulting in a change of emphasis from energy efficiency (based on running costs) to environmental impact (based on carbon emissions) with new builds having to achieve a carbon emissions target. SBEM calculations were introduced for non-domestic new-builds, again basing compliance on carbon emissions. There were also new requirements for minimum efficiencies of heating systems.
Energy Performance Certificates (EPCs) became a requirement under the 2007 regulations for new builds, to be submitted by the Applicant to Building Control on completion.
From 2009 EPCs were required for sale or rental of houses and sale of non-domestic properties.
From 2010 the carbon emissions target for new-builds was reduced by 30% compared to 2007 values.
2010 also saw the introduction of Certifier of Design (Section 6 – Energy) schemes, allowing accredited certifiers to take responsibility for certifying Section 6 (Energy) instead of Building Control.
2011 saw the introduction of air testing on completion of new builds.
From 2013 EPCs had to be registered on the Scottish EPC Register by members of an approved organisation such as Elmhurst or NHER
The 2015 regulations amendment saw the Carbon emissions target for dwellings reduced by 45% compared to 2007 and for non-domestic reduced by 60%. The majority of new buildings now had renewable or low carbon energy systems. The levels of air tightness meant that many dwellings had to have whole-house mechanical ventilation systems to ensure adequate air quality.
In 2016 the pioneering NHER ratings scheme was discontinued. The SAP ratings scheme had all but caught up in sophistication and was more widely used, rendering the NHER scheme almost obsolete.
The 2015 regulations continued to use the same SAP and SBEM procedures until amendments came into force in 2023, despite much of the data becoming increasingly outdated. For example, electricity generation had become much ‘greener’ with the rollout of renewable technologies, and the assumed carbon factors became progressively more inaccurate. In 2010 fosssil fuels had accounted for 75% of total generation, but by 2020 this was down to a little over 40%. Rather than being one of the highest emission fuels electricity had become almost the fuel of choice, especially when linked with heat pump technology.
The regulations introduced in February 2023 intend to deliver a 32% (domestic) and 20% (non domestic) reduction in emissions for new builds over 2015 standards. Going forward, it is expected that in 2024 the ‘New Build Heat Standard’ is to be adopted, for which heating systems must have zero emissions at point of use, although there will still be ‘carbon factors’ associated with delivered energy. This will effectively ban for example oil and gas conventional boilers, in favour of electric systems such as heat pumps, and heat networks (district/community heating systems).
The target carbon emissions rate for compliance remains for now, but only for so called ‘direct emissions’ systems which produce carbon emissions on-site, such as gas or oil boilers. Electric systems and heat networks do not produce on-site emissions, so are exempt from this. Following the introduction of the ‘New Build Heat Standard’ (due in 2024) it is expected that emissions at point of use will no longer be relevant for building regulations compliance,
The 2023 regulations also saw the introduction of a new metric defining delivered energy demand, where a target as calculated by SAP and SBEM procedures has to be met to comply with regulations. Delivered energy is not influenced by fuel type, but principally depends on building fabric properties instead.
