St George’s Church, Portsea

St George’s Church, Portsea

Application: Healthcare & Residential,Offices & Public Buildings,Churches & Historical Buildings

St. George’s Church in Portsea is a Grade 2* listed building and was built in 1753 by local dockyard workers, it was originally named the shipwright’s church.

The classification of Grade 2* listed is a building of particular importance with more than special interest.

The church is a fine example of New England colonial architecture representing Portsmouth’s links to the early American colonies.

The Church suffered significant damage during WW2 and was closed for ten years; further significant restoration was carried out in the 1950’s and 1970’s. Located close to the renowned Gunwharf Quays, means it is exposed to sometimes severe weather conditions. In 2012 it was identified that significant work was required to secure the fabric of the building. With support from a National Churches Trust and funding from the Heritage Lottery Fund, £167,000 was invested in making good the building for it to remain a viable community space.

In September 2018, St George’s became part of Harbour Church Portsmouth, which also encompasses St. Alban’s Church and All Saints Church in the city centre. The vision of Harbour is: ‘To play part in the re-evangelisation of the nation, the revitalisation of the Church and the transformation of society.’

Director of Central Services at Harbour Church, Josh Pearson said: ‘The church had no heating at all and was particularly cold through the winter months and, as a consequence, some essential services had even been cancelled. This clearly affected our local community and we were determined to do something about it. Fortunately we received funding from the Church Commissioners which enabled us to install a new heating system.’


Specialist renewable heating company, Bioheat Energy Ltd in Wincanton, was commissioned to design and install a new heating system. Mathieu Pavageau, design engineer at Bioheat said: ‘Churches are notoriously difficult to heat efficiently and effectively. They are generally big open spaces with high roofs, which can be an issue in itself. Furthermore, they are occupied occasionally, so there’s a need to heat the large space up very quickly. Of equal importance is the need to keep the aesthetics of heat emitters unobtrusive and in-line with the surroundings. Noise is always a big consideration and must be kept to an absolute minimum.’

Bioheat installed an energy efficient condensing gas boiler with full weather compensation interface. In simple terms the outside temperature dictates the boiler demand, so providing as much, or as little energy required to heat the space. The added benefit is the improved life expectancy of the boiler and associated components and clearly the reduced energy consumption and related costs.


The choice of heat emitters was vitally important to the success of this project and Bioheat contacted Jaga for help, knowing the company’s expertise in this area. Jaga had successfully designed and supplied heating solutions for a number of churches over the years and was well aware of necessary design requirements. Joe Franks, business development manager at Jaga said: ‘As well as normal church services, St. George’s serves the local community in many different ways and is used for many different events and groups. With this in mind, our proposal had to be robust enough and safe to cope with all types of activity and potential visitors.’

Standard steel panel radiators are ineffective in churches, they are slow to respond to heating demands and not particularly efficient at low water flow temperatures. Jaga’s tow water content heat exchangers hold 90% less water than conventional radiators and as a consequence respond very quickly to changes in temperature demand.

This means that the church can be heated up very quickly and respond rapidly to changes in demand.

Continuous Tempo


Joe added: ‘We put forward our Tempo low surface temperature range of highly efficient thermal heat emitters. These are safe to touch units with casing temperatures not exceeding 43°C. They also look great in continuous perimeter casing format, adding further character to the church architecture and decor.’

‘They were supplied with our ‘dynamic boost effect’ technology, basically fan sets mounted on the heat exchangers to deliver three times more heat than a conventional natural convection equivalent.

Jaga supplied thirteen metres of continuous Tempo each side of the main church hall, delivering in total an impressive 87kW of heat.’ ‘Due to the height of the church, we additionally supplied local perimeter heating units on the upper floor. These again incorporate our low water content heat exchangers with dynamic boost effect and were installed within the floor void.’

Commenting on the installation, Director of Central Services at Harbour Church Josh Pearson said:

‘We are delighted with our new heating system. We can use the church whenever we want and for whatever we want to use it for. It’s great to give the local community, as well as other visitors, a truly warm welcome. The system is so easy to use via a digital application and also with local override control when required.’ ‘Jaga’s equipment is whisper quiet and I would certainly recommend the company for customers with particularly demanding requirements.’

St. George’s is registered with Eco Church, an organisation that provides help, support and resource for five key areas of church life, one being management of church buildings.


Jaga UK is devoted to supplying great HVAC products through great people. We do this by designing and developing ecologically sustainable products that positively impact our planet and through working tirelessly to create a positive environment for our employees, customers and partners.

Our ideal world is built around our five core values that guide us and keep us focused on sustainability, creativity and social responsibility.

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