A project to transform a historic chapel into an arts centre is using heat pump technology to keep visitors warm, and fuel bills down.
Soar Chapel in Merthyr Tydfil is a listed building dating from the 1840s. A six-year, £1.4 million project has re-established it as a cultural centre for the local community, featuring a theatre, dance studio, music and multi-media rooms, teaching rooms, meeting and conference rooms, a shop and a café.
Dave Tucker of Cardiff-based installer partner WDS Green Energy says efficient heating was essential for the conversion. It was a technically challenging project, involving a variety of different-sized spaces over the three floors of the building.
The centre is now heated by two Dimplex ground-source heat pumps, combined with 20 SmartRad fan convectors and underfloor heating.
“Keeping the centre’s heating on over the winter using the old gas boiler system was costing up to £200 every week, so tackling running costs was a high priority,” says Mr Tucker.
“The heating also had to be reliable, since in the valleys the weather can be very raw. The recent severe winters have seen temperatures drop as low as -15 deg C, but we knew the Dimplex units would easily be able to handle that.”
The most dramatic part of the project involved halving the original height of the chapel, with the upper balcony level being converted into a 200- seater auditorium.
A newly created floor forms a central stage, surrounded by the chapel’s original pews, which now seat the audience. The design was especially careful to preserve the chapel’s beautiful original organ and pulpit, which now forms part of the stairway up to the stage.
“We’ve not been involved in anything like this before,” says Mr Tucker. “But with some creative thinking and support from Dimplex, the project came together beautifully.”
WDS and Dimplex’s heating design team realised that the stage itself could form the heat emitter, using low-temperature underfloor heating to meet the majority of the heat demand for the entire space.
Accordingly, the 90 sq m stage was fitted with pipework, covered by a concrete screed and finished with a wooden floor.
For supplementary heating, eight SmartRad heaters are located around the walls of the auditorium, providing additional warmth to keep the audience comfortable on even the coldest days.
The heaters give excellent performance at flow temperatures as low as 40 deg C, optimising the co-efficient of performance (CoP) of the heat pump system to reduce running costs and CO2 emissions.
A Dimplex SI 37 TE ground-source heat pump was specified to heat the main part of the building. Due to the limited space available around the chapel for ground loops, vertical boreholes were the natural choice, so six 100 m boreholes were drilled under the car park.
The vestry, bookshop and other parts of the building are heated by a Dimplex SI 30 TE ground-source unit, drawing heat from a further five 100 m boreholes. The two heat pumps are linked into one operating system to give control over the whole facility from one point, and a ventilation system recycles the heat.
In addition to the eight heaters in the auditorium, there are another 12 in the various practice areas, classrooms and meeting rooms in the lower two levels of the building.
These areas all had existing flooring, making underfloor heating a more disruptive and expensive option, and therefore less attractive.
Geoff Cheason from Penarth-based architect Lapider says: “The SmartRad fan convectors are very responsive, and they give a kind of heat that people feel comfortable with – if the room’s cold, they adjust the heaters. People are used to this type of heat, and so the heaters are just right for the smaller rooms.”
The project received financial support from a number of sources, including a £527,000 Heritage Lottery Fund grant, and the centre opened in the summer of 2011.
It now attracts a wide variety of users, including professional performance companies, the youth organisation Urdd Gobaith Cymru and the University of Glamorgan.
While true running costs have yet to be established as the winter heating period ends and building use and management begins to settle down, it is anticipated the new heat pump system will significantly improve on the old system’s performance.