Binsted, North Hampshire

Located in a village in North Hampshire, this approximately five hundred square metre, grade one listed barn was constructed around 1230AD. Although due to extensive insulation efforts, the maximum heat load is only approx 16kW. Such an old and protected structure was going to be a real challenge for all involved in its conversion and renovation.

The barn’s current owner has been undertaking the process of converting several outbuildings on the site, previously converting an oast house to a dwelling. The conversions were to provide character properties to be rented for income. Having used a ground source heat pump in the oast house the owner was keen to use renewable energy on this project, as the Renewable Heat Incentive would provide him with an additional income to the property’s rent. However, unlike the oast house, there was little in the way of land available for the installation of ground loops or boreholes.

After discussing the options with a representative of the heat pump installation company he decided to use an air source heat pump solution. Though large, a master/slave arrangement of two Vaillant Arotherm 15kW heat pumps could provide all the heating energy required for the property, even with sub zero temperatures outside! The system also provides hot water via a 500-litre, heat pump specific, hot water cylinder and is controlled by Vaillant’s user friendly VRC700 controller. The two heat pumps themselves are linked at a 200-litre buffer, which stores water for the underfloor heating. Rehau insulated pipe was laid the 15 metres between the barn and the garage to carry the hot and central heating water.

Being nearly eight hundred years old this building certainly never had any heating system and the overall finished design was very minimalist. For that reason, underfloor heating was chosen to distribute the heat throughout. All the underfloor heating can be controlled via a simple app from any smart phone or tablet.

The customer was very happy with the finished result of the project and has successfully completed an application for the Renewable Heat Incentive, which based on results so far should be enough to entirely pay for the plant equipment that was installed in the property. He now looks forward to many years of enjoying what is now the oldest habitable barn in the United Kingdom!