London and Copenhagen take different approaches to urban noise, researcher finds

London and Copenhagen face a shared problem from roads, railways and airports, but England and Denmark make different planning choices about noise, researcher Francesco Aletta wrote in an analysis published October 9. Denmark uses a national guideline in decisions about where homes can be built, while England gives local planners more room to balance noise against housing and economic growth. The distinction matters to residents because long-term exposure can disturb sleep and is linked to other health risks.

Aletta’s comparison, published by The Conversation and republished by Phys.org, examines how much noise each country accepts as part of urban life. It is an analysis of existing approaches, rather than an announcement of a new rule. Nor does it show that one country’s planning choices have caused a measured improvement in health. Both capitals experience substantial transport noise, and Aletta cautions against treating Copenhagen as a quiet exception.

How Denmark and England weigh noise in planning

In Denmark, the national guideline for road traffic noise is 58 decibels. Aletta describes the country’s approach as treating noise as a planning and public-health concern, with the guideline informing decisions about where housing can be built. The measures he discusses include lower speed limits, noise barriers and better insulation. A guideline does not mean all existing homes meet it: the Danish Environmental Protection Agency says almost one in three homes is exposed to road noise above the recommended limit.

England has no equivalent national noise threshold that acts as a cutoff for further development, according to Aletta. Local planning authorities can consider noise alongside the demand for housing and economic growth, making decisions case by case. That flexibility means residential exposure can vary. The comparison identifies a difference in how planning decisions are made; it does not establish that either approach has eliminated harmful exposure.

The agency also describes five demonstration partnerships started in 2005, in which authorities and residents helped finance noise abatement. Residents contributed about 40% of DKK 13 million in construction costs, it says. According to the agency, 500 residents in 250 homes reported improvements to their homes and quality of life. Those projects illustrate one way mitigation has been funded; the agency’s account does not establish a nationwide outcome from that model.

Why the exposure figures cannot rank the countries

Aletta reports that about 16% of Denmark’s population, roughly 918,000 people, is exposed to transport noise above recommended levels, mostly from roads. He also reports that around 40% of adults in England experience long-term road traffic noise above 50 decibels. The figures measure different populations and apply different thresholds. They cannot be read as a direct comparison of the two countries’ exposure, still less as a score for their planning systems.

The Danish Environmental Protection Agency puts the number of homes above its recommended road-noise limit at about 785,000, or almost one in three. Its traffic-noise page recounts older strategy and evaluation work, including material from 2003 and 2010. Those figures should therefore be understood as figures cited by the agency, not as newly collected measurements announced with Aletta’s October analysis. Its account also concerns homes, while Aletta’s national exposure figure concerns people.

What European noise data show

The European Environment Agency’s 2025 report provides a wider measure of the problem. Drawing on data submitted under the 2022 reporting round of the Environmental Noise Directive, it says more than 20% of Europeans are exposed to harmful transport noise. Against the stricter recommendations of the World Health Organization, the share rises above 30%. Those results use their own reporting framework and do not resolve the England–Denmark comparison.

Road traffic is the largest source in the agency’s estimates: 92 million people are exposed above its day-evening-night threshold of 55 decibels. It estimates 18 million people affected by rail noise and 2.6 million by aircraft noise. The agency says the number of people highly annoyed by transport noise in the EU fell by an estimated 3% between 2017 and 2022, and concludes that the bloc is unlikely to reach its 2030 noise-reduction target without additional measures.

The European agency notes that it corrected several numerical estimates for health outcomes in March 2026, while saying the corrections did not change its overall conclusions. The remaining question raised by Aletta’s comparison is how planners weigh noise when they make decisions about homes and transport. The available exposure figures show that noise remains widespread; because their thresholds and populations differ, they cannot establish which capital has less harmful exposure or which planning approach works better.