Retrofitting our existing housing stock to make it fit for 21st century living is a win-win. Though not cheap, it is an investment in the long-term for people and planet. As clients and governments become more ecologically aware, enthusiasm for sustainable retrofit of our existing buildings is growing.
Having carried out several historic and sustainable retrofits in Midlothian, mostly as part of the CARS (Conservation Area Regeneration Scheme), Halvorsen Architects is being asked to do more and more similar projects.
At present we are working on several buildings of various sizes on the Balcaskie Estate in the East Neuk of Fife. They are all Georgian sandstone buildings and of varying degrees of neglect.
Balcaskie is an example of an estate that is repurposing its buildings incrementally and organically, responding to the demands of local tenants and trades. Toby Anstruther, who owns the 2,000-hectare (4,940 acre) estate, wants to make this part of the East Neuk an attractive place for people to live and work by fomenting a greater sense of community. He has been doing this, with his estate manager Sam Parsons, since 2008, soon after taking over the farm from his father. It had been intensively farmed. Now it is regeneratively farmed.
Most of the existing buildings are being repurposed as homes, offices or workshops. There is also a children’s nursery and an indoor food market – Bowhouse. There are a diverse range of businesses operating out of the converted buildings from a camper-van repair outfit to bijou craftsman. Typically, like-minded tenants are clustered together around a key tenant creating a community of interest. A recent Financial Times article, The local heroes of Balcaskie, describes the tenants in one of the creative clusters as including a knitwear label, bespoke guitar maker and a stained-glass window designer. The tenants describe how they find stimulation and companionship from the shared kitchen, meeting room and garden. This helps tackle the potential problems of isolation that can arise from self employment and more homeworking following Covid. Opening the nursery was an important first step to enable flexible working patterns.
However there are many obstacles thrown in the way of such developments, not least the fact that VAT is applicable to renovation and extensions, but not new builds. This is a national scandal, for which the Westminster government is responsible.
The planning system also struggles to keep pace with sustainable developments along such lines. Because of the scale of the projects, junior planners with insufficient knowledge are allocated to them. We need a more sophisticated planning system that is capable of facilitating multiple small-scale but complex rural developments. As Sam says “simplification and streamlining” is not going to help.
Retrofit is not something that can be applied equally across the board. At Balcaskie Estate, Halvorsen Architects is advising more broadly on the sustainable retrofit of existing building stock. We have drawn up an easy-to-use template of alternative methods with a pick’n’mix list from which to choose. There is no one-size-fits-all solution. Decisions about aesthetics, buildability, costs and the condition of the existing fabric have to be balanced as do planning and building regulations. For example should insulation be on the outside or the interior? There are many factors to consider and pros and cons for each. Preserving historical features could sacrifice levels of insulation or airtightness. And once these decisions have been made, comparisons need to be made between the alternative natural materials such as wood-fibre, hemp, sheep’s wool, or flax. We compare their levels of insulation, thermal storage capacity, durability and life-cycle impact, taking into account the level of expertise needed to install each.
It becomes even more complex when an extension is involved. Positioning the extension on different sides of the building will have significantly different effects – on the north side it could be designed as an additional layer of insulation whereas on the south side, it could act as a sun space capturing heat.
With retrofit, it is impossible to achieve levels of insulation that can be delivered with new build. However Balcaskie Estate is slowly installing a variety of local renewable energy systems for each farm-steading and so, on balance, the lower levels of insulation are considered sufficient. We will however be targeting extremely high levels of airtightness, similar to what can be achieved in a Passivhaus building. This will significantly help retain heat inside the building. These are the typical sorts of trade-off that have to be made with retrofit.
A lot more time needs to be spent on retrofit design but it is this organic transformation of our rural landscape that people are crying out for – preserving our heritage while protecting the environment and making places where, thanks partly to the joys of high-speed broadband, people actually want to live and work.
