By Mark Harris.
In the current climate of soaring energy prices, a slow construction market and possible fiscal incentives, the refurbishment of existing buildings has become less a question of whether or not to do it and more one of how far to go with it. As much as 77% of our 1.8 million current stock of non-domestic buildings were built before 1985 (source BRE) and since it is estimated that 60% of these will still be in use in 2050, the need to bring many of them up to standard and upgrade their thermal performance is pressing.
Renovating these buildings also represents a major investment, so it is increasingly important that the optimum solutions are found to achieve the necessary energy savings and give the best return. In recognition of the complexities involved, Kingspan has recently commissioned two of the most respected independent consultancies in the industry – Elmhurst Energy and Cyril Sweett – to produce an industry leading piece of research, which examines the different benefits of four cumulative retrofit strategies, and takes into account the CO2 and cash energy savings over 25 years.
The research took four different case studies: a school, an office, a retail unit and an industrial unit, and applied four stages of retrofit to each. The first stage, Retro-1, was to tackle the building envelope, increasing levels of insulation and airtightness in line with the requirements of Approved Document L2B (ADL2B) to achieve improvements in energy efficiency.
The second stage, Retro-2, was to look at the efficiency of heating, cooling, lighting and other building services, also in line with ADL2B. Building envelope improvements must have been made first, as the efficiency of the building fabric can significantly affect the sizing, specification and operation requirements of the building services.
Retro-3 involved the addition of renewables. Retro-4 was essentially a deep retrofit and an advanced combination of the first three stages. This level of retrofit can lead to CO2 emission reductions of 80% or more, and even greater energy savings.
The results were encouraging, highlighting the potential for significant savings over the 25 year life assigned to the improvements. For a full breakdown of the results contact me on the email address below, however here are a few highlights:
- The maximum savings in CO2 and Energy were found by undertaking a deep retrofit of an industrial unit, these were 83% and 86% respectively
- The highest cost saving was achieved by undertaking a deep retrofit of an office building and saving almost £1m over 25 years and reducing the energy usage by 80%
- Even undertaking a basic, EnvelopeFirst retrofit of an industrial unit saved 70% in CO2 , 80% in Energy and almost £300,000
One thing is certain; refurbishment today is an essential part of the construction industry, and it could play a vital role both in our economic recovery and in improving our energy security over the coming years. It can also create significant carbon savings for businesses involved in the CRC Energy Efficiency Scheme. Getting it right could make all the difference in the achievement of these goals. Getting it wrong, by opting for renewables without first maximising building envelope performance, for example, could be a missed opportunity.
Kingspan Insulated Panels’ Retrofit team can to complete a comprehensive energy assessment and provide the expertise and information to let you make the most of these opportunities and decide just how deep you should go.
Mark Harris, Building Technology Manager, Kingspan Insulated Panels. firstname.lastname@example.org