Retrofitting a listed home
12 St. Swithun Street, Winchester, Hampshire, SO23 9JP
See how the owners are tackling the urgent need to reduce energy consumption and greenhouse gas emissions in a Grade II listed building in a conservation area. Includes details of materials, architect, specialist advisers, planning permission and installers.
● Air source heat pump supplies all space and water heating in the property.
● Two types of heat exchange fans.
● The roof space has extensive insulation with hemp and Diathonite plaster to make rooms in the roof warmer in winter and cooler in summer solar.
● All walls are solid. Some have been ‘papered’ with V600 thermal liner, others have been replastered with Diathonite Thermactive .037 insulating lime plaster.
● Inefficient conservatory replaced with highly efficient triple glazing, and walls lined with wood-fibre insulation.
● On the cold ground floor, a layer of high-efficiency insulation has been added below the wooden floorboards.
● New double-glazed windows installed by ensuring traditional external and internal appearance and using inert gas filling and a barrel glass external layer.
● Triple glazing of historic windows by using double secondary glazing.
● On the rear roof, south-facing photovoltaic solar panels have been allowed because they are partially concealed.
● Energy-storing batteries help make the best of the limited output of the photovoltaic solar panels.
● A new high-spec wood burning stove was installed before the owners knew about the air pollution caused by stoves.
Timings & Tours
- Friday 19 September:
- 1000-1700
- Saturday 20 September:
- 1000-1700
Location & directions
12 St. Swithun Street, Winchester, Hampshire, SO23 9JP
- Directions:
- There is no on-street parking available in the immediate area. Park and Ride bus stop on Westgate is approx 10 mins walk - https://www.winchester.gov.uk/parking/park-and-ride/. Railway station approx 15 mins walk.
- Contact on day:
- Christine Holloway
- Telephone number:
- +447779283451
Booking information
- Pre-booking requirement:
- Pre-booking preferred
- Booking conditions:
- Booking via Winchester Heritage Open Days
- Booking contact name:
- Hampshire History Trust
- Booking email:
- [email protected]
- Booking website:
- https://www.ticketsource.co.uk/hampshire-history-trust
- Booking opens:
- 08 Aug 2025 12:00 AM
- Booking closes:
- 10 Sep 2025 12:00 AM
Accessibility details
Flat access through wide door to garden. Main access to ground floor is up a small step. One step change of floor level between front and back of the house. There's a WC on ground floor but it's not wide enough for some wheelchairs. 1st and 2nd floors are accessible only by stairs.
Additional information
Hazards: pond in garden; low doors Free retrofit/home energy advice available via WinACC's My Home Made Better project - https://www.winacc.org.uk/retrofit-for-older-homes/
- Max no of people per tour:
- 16
- Est. tour duration:
- 1 hour(s)
