Despite the urgent need, very little work is currently being undertaken for the primary purpose of improving energy efficiency and reducing carbon emissions in the UK’s existing commercial building stock. Most often improvements are driven by commercial or operational necessity: through redevelopment projects, major refurbishment, occupier fit-outs, or the replacement of equipment at the end of its service life.

Where low carbon retrofit is considered, it is usually on the basis of either a simple economic payback or a CSR driven agenda to reduce carbon emissions in owner occupied buildings or single tenanted premises on a long lease term. This works best in these situations as the benefit of any investment in retrofit is directly attributable to the party making the investment and the long term association with the building helps to underpin the business case.

Making a business case for low carbon retrofit in multi-occupied buildings is more difficult. The complexity of leasing arrangements, varying lengths of tenure and the split incentives, which do not always align the party making the investment with the benefits accrued, often conspire to frustrate potential improvements. Where investments are made they are usually driven by a financial or business imperative, rather than to improve energy efficiency and reduce carbon emissions. For example, to encourage an existing occupier to extend their lease, reposition the building in the marketplace, reduce voids or to replace failing plant and equipment. Additionally, such works can be disruptive to the workspace and it is much easier, therefore, to undertake them when part or all of the building is vacant. For this reason owners are understandably reluctant to carry out retrofits when buildings are fully occupied

Nevertheless there are two key retrofit activities that stand out as major carbon-reducing opportunities in multi-occupied commercial properties. These are low-disruption retrofits intended specifically to improve energy efficiency; and accelerated replacement of existing services equipment.

This study identifies the main barriers limiting the uptake of low carbon retrofit in the marketplace and provides a low carbon retrofit roadmap to help overcome them supported by BBP members’ case study examples.