Organisations and individuals charged with managing historic buildings face a significant challenge.
How do we respond to the climate crisis whilst ensuring the people using our buildings are comfortable and protect the precious fabric and interiors?
How do we make changes urgently whilst minimising the risk of maladaptation?
How do we heat buildings in the context of UK net zero targets, UK energy strategy, and increasing energy costs?
These were just some of the questions discussed at a recent national conference, organised by the Fit for the Future network, Church of England, and Historic England.
The sold-out conference included presentations from a range of speakers with Places of Worship being a prominent feature. The focus was to provide practical, feasible and where possible proven technical solutions and approaches for a range of historic building types with a variety of uses.
- In terms of the technology, it is possible for church buildings to be net zero carbon and none of the recommended heating technology represents a significant risk to the heritage.
- There is no single heating technology recommended for church buildings.
- A detailed technical feasibility study must be carried out at the early concept stage when replacing a heating system.
What is needed to help us achieve net zero carbon?
- Remove VAT on retrofitting and maintenance.
- Systematic upgrading of electrical supply particularly in rural areas.
- A long-term strategy from the Government, not a piecemeal approach, to give certainty to the industry.
- Address the shortage of materials and skills.
- Train more people in order to give reliable information that is tailored to the needs of achieving net zero carbon and heritage buildings.
- People to work to an agreed standard.
- Accessible funding.
A Few Notes on Some of the Options Available
Air Source Heat Pumps (ASHPs)
- ASHPs are increasingly the first solution people think of when replacing fossil fuel boilers, but they aren’t appropriate for all church buildings, this is why a detailed survey is so important.
- ASHPs are designed to maintain a comfortable level of heat, so they work best when kept on continuously in buildings used daily.
- They do not function like gas or oil boilers which heat spaces relatively quickly to higher temperatures; oil and gas boilers work at 70-80 degrees, whereas ASHPs work at 30-50 degrees.
- The success of an ASHP relies heavily on good design and optimisation. A lot of negative experiences with ASHPs tend to come from the fact that the pump that has been provided just isn’t the right specification for the building type and usage.
- It is also important to remember that ASHPs need electricity to function, so they will not will automatically save you money on energy bills, particularly if your church is used less than 12 hours a week.
- They are also very costly to install. This will hopefully change as the range of products and skills in the industry improve.
Direct Electric Heating: Pew Heaters
Pew heaters, panel heaters and overhead heaters are considered a better option for churches which are only used weekly or less. They are designed to heat people and not the whole building. Pew heaters are a particularly popular option as they are:
- Energy efficient – no pre-warming required; heat the occupied pews
- Safe – thermal cut-out; built in guards
- Compatible – fit any style of fixed pew
- Unobtrusive – silent, discrete, brown finish
The main drawbacks are that they:
- require fixed pews to be mounted to;
- may require the electricity supply to be upgraded which can be costly;
- do not heat the whole building so are unlikely to help with damp issues.
Biomass boilers can be an option for some churches, but it is important to remember a few key things:
- they require space for the plant and storage of the fuel, as well as good access to deliver the fuel;
- breakdowns can be common if fuel is stored incorrectly;
- boilers need manual loading of fuel and regular maintenance.
- Using 100% hydrogen in the gas grid across the UK to displace natural gas has challenges that can probably be overcome with investment and time. That is likely to be 10 – 15 years away – if ever.
- The fastest way to decarbonise now is to replace gas boilers with electric heat pumps. Waiting for hydrogen is not helping the climate emergency.
Advice for Churches
Read The Practical Pathway to Net Zero produced by the Church Buildings Council. This is a summary of how churches can reduce their energy use and associated carbon emissions. It has advice for low occupancy churches through to more advanced projects for churches using more energy.
They key message is to work out what your church needs rather than just replacing existing boilers with new products. For churches which are used weekly or less, the focus should be on low level interventions such as keeping on top of maintenance and switching your energy supplier.
If you are considering changing your heating system because it has reached the end of its life (or will soon), it is important to appoint someone to carry out a holistic survey of the church building and it’s use, rather than someone who has a vested interest is selling you a particular product.
A detailed technical feasibility study must be carried out at the early concept stage, as the type of heating system will be affected by many factors including the:
- Building site and location
- Size and form of the building
- Use and operation of the building
- Condition of the existing heating system
- Existing utility infrastructure
- Potential future uses of the building
If you have any queries or concern, please contact staff in the Church Buildings Team.