Homeowners often ask about heat pump noise, particularly from air source and air-to-air systems, including concerns about fan noise and operation during cold nights. They also raise concerns about noise regulations and how they might affect heat pump installations.

"Oh, and I almost forgot, how noisy is an air source heat pump?"

"How noisy are the latest air-to-air heat pumps?"

"Are the fans of the external units really that noisy?"

"Just curious, but when outside at night when [it is] very cold, have you ever gone into your garden to hear how loud it is?"

"If it is, how’s the noise level?"

Heat pumps are designed to be relatively quiet, with most ASHPs producing noise levels similar to a typical gas boiler. GSHPs are generally even quieter. A Nesta survey found that 85% of heat pump owners were satisfied with their heat pump's noise levels, often describing them as unobtrusive.

In residential areas, the cumulative noise of multiple air source heat pumps operating simultaneously is unlikely to significantly exceed the noise of a single unit even under worst-case scenario assumptions. This means that current planning noise limits for individual heat pumps are effective at preventing any significant noise effects from multiple installations. While some noise may be noticeable at close range or during colder weather when heat pumps work harder, careful placement, such as near fences or away from windows, or installing acoustic barriers and enclosures can help mitigate noise impact further. 

"Would the same environmental health regulations concerning noise apply to all forms of heating, or are heat pumps singled out?"

"Are Ipswich Borough Council going to block the installation of environmentally friendly heating solutions in Ipswich forever based solely on noise?"

Installing a heat pump in the UK is subject to planning regulations. In England, in many cases, installing a heat pump can be done without needing planning permission, as part of permitted development rights, as long as certain criteria are met. These include adhering to noise limits of 42 decibels (dB) within 1 metre of a neighbour's windows and limits on the size and number of heat pumps. It is worth noting that planning rules vary slightly in Wales and Scotland, where more stringent rules related to where the heat pump can be placed in relation to the property boundary exist. 

In the UK, environmental health regulations apply broadly to all noise-generating equipment, including heating systems. This gives local authorities the power to investigate noise complaints and determine if they constitute a "statutory nuisance." However, research into noise complaints about heat pumps shows they are rarely a source of significant concern. A study of Freedom of Information (FOI) requests found that 124 councils reported no noise complaints between 2020 and 2023, while only 42 councils recorded a single complaint each.