Energy efficiency and house prices

One of the issues I explore in the forthcoming book 'The Future of Planning' is whether it is possible to improve properties and areas without triggering gentrification and the associated increase in property values. The key idea is that the stock of low priced housing and the local environment of low priced neighbourhoods often needs upgrading to improve the quality of life of residents; but the tendency for the market place to capture these new benefits in higher property values, while benefiting property owners, can often be disadvantageous for tenants and existing SMEs, who may face competition from people and businesses with deeper pockets. So the question is what kind of improvements enhance local people's quality of life without leading to upward property price moves and the wholesale shift in local communities (business and residential) associated with gentrification? It did seem that energy efficiency improvements were one answer to this question. Investment in such efficiency measures reduces energy bills and combats fuel poverty and, so it seemed, did not lead to much in the way of price movements. Recent research conducted for DECC suggests this may be changing:
www.gov.uk/government/publications/an-investigation-of-the-effect-of-epc-ratings-on-house-prices.
On average there seems to be an impact of £16,000 additional value from raising the EPC rating by two 'levels'; this equates to an average increase of 14% but the impact is much higher in low priced areas. The study has been done by real experts in this kind of analysis (McAllister, Fuerst, Nands and Wyatt) but as ever there are caveats: the analysis could not control of the condition of the properties or home improvements between sales. But taking the general finding as sounds, this raises important questions. This is good news for home owners and should encourage retrofitting. What how will this impact on tenants? Is there a differential take-up on efficiency measures that means that lower income households, includng home owners, are not getting the benefit of this price shift? An analysis of the social distribution of these price impacts and the take-up of public subsidies for retrofit would be very timely.