Over the past few years, it’s become easier and easier for homeowners to install green heating systems in their houses. Air source heat pumps have now joined the likes of biomass boilers and thermal panels as Permitted Developments in England, Wales, Scotland and Northern Ireland, providing certain requirements are met.
What this means is, for the majority of homeowners, you no longer need to worry about applying for planning permission to install a heat pump. However, we always counsel readers to err on the side of caution – call your local planning authority and double check with them. Your local MCS-certified installer can also answer any questions you may have regarding planning permission for a heat pump in your area.
Planning permission for air source heat pumps
So long as your heat pump installation complies with the following Permitted Developments criteria, you won’t have to apply for planning permission. However, these criteria vary slightly in different countries in the UK. In Scotland for instance, the air source heat pump’s external unit and housing cannot exceed 3 metres in height, but in England, the unit mustn’t be larger than 0.6m³. Remember – when in doubt, check with your local planning authority.
- Your air source heat pump is only used for heating (space heating and hot water).
- The installation complies with the Microgeneration Certification Scheme Planning Standards (MCS 020). It’s the responsibility of the installer to ensure that your heat pump installation is compliant with MCS standards.
- Only the first air source heat pump falls under Permitted Development rights – adding a second would require planning permission.
- Similarly, an air source heat pump is a Permitted Development on the condition that there isn’t a wind turbine on your property. If there is, you’ll need to apply for planning permission.
- The air source heat pump must be removed when it’s no longer in use.
- The heat pump must be sited in a way that minimises its effect on the appearance of the building and the amenity of the area. This may involve siting the external unit at the back of the house, out of view from the road, or if you’re fixing it to a wall, it must be below the first storey.
- The air source heat pump must be installed on flat surfaces. You may be permitted to site the external unit on a flat roof providing it’s at least 1 metre from the roof’s edge, but check with your local planning office to be on the safe side (England, Scotland and Wales only).
- If your home is a listed building or scheduled monument, you’ll have to receive listed building consent prior to the installation.
- If your property is situated within a conservation area or World Heritage Site, you’ll have to check with your local planning authority to check whether air source heat pumps are deemed Permitted Developments.
- Size of external compressor: in England, the outdoor unit and housing isn’t larger than 0.6m3. In Wales, the compressor unit and housing can’t exceed 1m3, in Scotland, it can’t be taller than 3 metres, and in Northern Ireland, the external unit must be no taller than 2 metres.
- Distance from boundary / nearest house: in England and Scotland, the air source heat pump must be at least 1 metre from the property’s boundary. In Wales, it must be more than 3 metres, and in Northern Ireland, the external unit must be more than 30 metres away from the nearest house (other than your own).
- The external unit can’t protrude more than 1 metre from the outer wall, roof or chimney of the dwelling.
Sourced from Town and Country Planning, England 2011, Wales 2012, Scotland 2016, & N. Ireland 2015 (General Permitted Development), legislation.gov.uk
MCS Planning Standards and noise level requirements
The MCS Planning Standards (MCS 020) stipulate that noise levels for an air source heat pump on its own must stay at or below 42 decibels (dB) from a metre distance away from any habitable room. Where there is a wind turbine already installed, the total noise pollution from both microgeneration technologies must not exceed 42 dB. If it does, you’ll need to get planning permission approval.
Planning permission for water source and ground source heat pumps in the UK
Water source and ground source heat pumps fall under Permitted Developments rights in England, Wales and Scotland, so long as the heat pump stays within the curtilage of your home, doesn’t exceed 0.5 hectares, there’s only one heat pump on site, and it’s removed as soon as possible when it’s no longer in use.
We always counsel checking with your local planning authority just to be on the safe side.
Grid Connection for a heat pump
Installing any heat pump adds a significant demand for electricity on the local grid. For this reason, the local Distribution Network Operator (DNO) will need notifying once the installation is complete. The good news is that this is for the installer to do – you won’t see any documentation or paperwork for this part of the installation.