Park Hill housing estate in Sheffield © Urban Splash
Repairing and repurposing historic properties could play a significant role in helping the UK government meet its target of providing 1.5m homes over the next five years.
Developers cautious despite benefits of repurposing
Converting historic properties makes sense on economic, social and environmental grounds. They are often more attractive to buyers than new buildings, with some properties worth up to 9% more just through proximity to a listed building or a conservation area.
Besides reducing the need to build on green belt land, historic regeneration projects can even contribute to meeting net-zero targets by capitalising on existing embedded carbon.
Yet many developers – especially small and medium-sized firms – are reluctant to take on such projects, daunted by a perception of significant hidden costs and labyrinthine regulations.
To demystify heritage housing projects and offer developers a clear guide to the process, Historic England and Deloitte together published Heritage works for housing in September. It shows how to minimise risks at every stage of projects, from acquiring a site to occupation and management.
This is complemented by a range of case studies from large-scale developments, such as Urban Splash's regeneration of the vast grade II* listed Park Hill housing estate in Sheffield, and the Watch this Space Wood Street Townhouses development in Manchester alongside the conversion of a former mission building into five residences.
Understanding and engagement reduce risk
Crucial to the successful repurposing and refurbishing of a historic property is feasibility testing. Taking time to understand potential problems, costs and design options will help reduce risk at all stages of development.
When developer Almacantar was planning to repurpose the grade II* listed 34-storey Centre Point building in central London, for instance, it carried out an extensive feasibility review before purchasing the site.
This included establishing whether the conversion of the office block into residential use would be acceptable in principle, and whether such a scheme could remain sensitive to the site's heritage significance. This helped to realise its vision to transform the building into 82 new homes with the overall project completed in 2018.
Carrying out a heritage appraisal to establish the areas of greatest historic and architectural significance – building on an initial assessment made at the time of purchase – can play a pivotal role in design development and in avoiding potential delays in the planning process.
Engaging with Historic England and the local planning authority can be useful at this stage.
Stripping building back may clarify work needed
Before the main works begin, a soft strip can also help to reduce risk by providing more programme and cost certainty.
This involves removing non-structural items of no heritage significance to reveal hidden elements of the historic property, offering clarity on a particular aspect such as structural condition or the potential presence of asbestos.
After securing planning permission for the conversion of the grade II* listed St James' Hospital in Portsmouth into 151 homes in 2019, developer PJ Livesey undertook such early works to better understand the condition of the building. This will help inform the detailed design process before main works commence on site.
Combining new and old can enable viability
Incorporating a new building element is another way to ensure the economic viability of historic property reuse.
When Manchester-based developer Watch This Space looked at converting a 19th-century former mission building in the city, it realised that the project was not financially viable on its own owing to challenges around optimising the building envelope.
However, the addition of two sympathetically designed new-build residences on the site of an adjacent former car park enabled the scheme to be profitable, with the project completed in 2021.
Historic England is using a similar approach on a larger scale at Shrewsbury Flaxmill Maltings. The organisation is planning to sell the surrounding brownfield land for new housing to help fund the restoration of some of the site's listed historic properties, with the developer partner expected to be announced in the summer.
Engage community on future of heritage
Perhaps the most important piece of advice to anyone looking at a historic property conversion is to engage with stakeholders at the earliest stage.
Communities have great affection for their historic properties and will want a say in their future. Getting them on side early through meaningful engagement will give a project a better chance of success.
Duncan Wilson is chief executive at Historic England
Contact Duncan: Email
Related competencies include: Conservation and restoration, Design and specification, Development/project briefs