Air Source Heat Pump System at Brixton Baptist Church

The brief for the project was to replace the church’s ageing gas heating system, which was no longer fit for purpose, with a new energy-efficient system which met the client’s goal of embracing the green heating revolution. They wanted to slash their carbon footprint, cut their energy bills and reduce ongoing maintenance costs. The client was also seeking a cost-effective way of cooling the building in the warmer months.

Our initial energy survey identified a major heat loss problem arising from the height of the main hall ceiling (c. 15 metres). This meant a considerable waste of energy as hot air rose into the unoccupied roof space rather than heating the main hall. An additional comfort issue flowed from the lack of a dedicated heating supply on the 1st-floor gallery where many people sit during services.

Ash Technical Services reviewed the renewable heating options available. We advised that the most energy-efficient method of warming (and cooling) the church – given building size, design and budget constraints – would be to install an air source heat pump (ASHP) system.

To tackle issues arising from the building design, we also agreed with the client that we would:

• Install high-level ceiling fans on the underside of the roof trusses to reduce waste and drive heat down into the occupied areas.

• Install discrete ASHPs on either side of the 1st-floor gallery to supply warm air to the entire floor.

We agreed on a programme of work that would allow us to operate around ongoing church activities and minimise disruption to church users. From the outset, we worked closely with the church’s Estate Manager to ensure all works were carried out safely and respected the ‘live’ church environment.

Ash Technical Services supplied weekly project updates to Paul McKnight, the Estate Manager, to ensure he was aware of developments and could inform church users and board members of progress.

We successfully installed the new ASHP heating system, carried out full electrical testing and inspection, undertook remedial work on the electrics to ensure the safety of the building’s users, and replaced the existing (non-compliant) hot water system.

The five-week project was delivered one week earlier than the contracted completion date. It exceeded the client’s brief in our provision of a total building support package above and beyond their expectations.

During the project, we successfully overcame several challenges linked to the church’s existing infrastructure, including:

• Having to erect scaffolding in the hall’s main seating area to safely access the 10-metre-high roof trusses.

• Dealing with incorrect or non-existent service records for the electrical infrastructure (due to the age of the building and multiple changes and adaptions over the years).

• Rectifying major issues with the electrical systems that emerged as work progressed.

The project has delivered a range of benefits, including:

• Delivery of an energy-efficient, cost-effective heating and cooling system that can be used all year round. (ASHPs can significantly reduce energy bills over the long term, and we will be monitoring usage throughout the year to quantify the savings for the client.)

• Peace of mind for the client that the church is compliant with Building Regulations requirements for electrical testing, fire alarms, emergency lighting, gas certification, and ongoing service plans to maintain safety and compliance.

• Modernisation of an historic building, in keeping with its original design, that allows it to maintain its important role in the community.

• Significantly greater comfort levels for staff, worshipers and other building users.

• Provision of a low maintenance system requiring annual or biannual servicing based around cleaning filters, checking refrigerant levels and clearing any leaves and debris from the outside condensing units.