You viewed at two on a Saturday afternoon and it was quiet. The agent said the road "calms down after six". The pub on the corner looked like the sort you'd want on your corner.

Here's the plain version. Noise is four or five different problems that happen to share a word, and each one has its own dataset, its own law, and its own time of day. Nothing you can look up was measured at the house. The maps are computer models, the airport contours are annual averages, and the only instrument that has ever been pointed at that specific bedroom window is you, on a visit, at the wrong time. So the job is to find the right time, and to know which map to distrust for which reason.

This is England. The maps and the law differ elsewhere in the UK.

What it actually is

It isn't one number. A main road is a steady hum that peaks at rush hour. A railway is intermittent, and half of its problem is vibration through the ground rather than sound through the air. A flight path is a sequence of events that follow a schedule and the wind. A pub is people, at the hours people are loud. A map that scores a street 60 dB tells you almost nothing about which of those it is, and the fixes are different for each.

The maps are modelled, not measured. Defra's strategic noise maps for England, the dataset every "noise map" website is ultimately drawing from, are the fourth round of mapping under the Environmental Noise (England) Regulations 2006. The current round was created on 24 October 2024 from analysis done in 2022, covers "all road traffic sources" and railways, and is "modelled on a 10m grid". The headline figure is Lden, an annual average over 24 hours "with a 5 dB(A) penalty for evening noise (19:00-23:00) and a 10 dB(A) penalty for night-time noise (23:00-07:00)". Nobody went out with a microphone. The model knows how much traffic a road carries and how fast; it doesn't know that the lorry route changed in 2024 or that the bus stop is outside your window.

And it's airborne only. Ground-borne vibration from trains, the thing that rattles a glass on the shelf, isn't in any public map.

Nookaly's quietness score is in the same family. It's computed from the road and rail network around the property, using OpenStreetMap road classes and distances, with no measurement involved. It's a screening figure, like Defra's, and it's honest about that. The rest of this post is what to do after the screening.

Main roads

The road map is the most useful of the four, because road noise is the most predictable. If the model says the front of the house sits at a high Lden, it will, and the daytime hum will be roughly what the model says.

What the map won't tell you is the shape of it. Rush hour on a commuter route, night buses, the difference between the front bedroom and the back one. Nor whether the windows are the reason it's bearable.

Our own data gives a sense of scale. Across active listings in and around London in September 2026, only about 7 per cent have no major road at all within 300 metres, and roughly one in five sit close enough to a big enough road to score in the top half of our index. That's modelled from the road network, not measured, and it says nothing about any one listing. It does say that "on a main road" isn't an edge case in a city; it's a fifth of what's for sale.

One legal point worth knowing before you complain to anyone. Section 79 of the Environmental Protection Act 1990, the statutory nuisance regime, excludes traffic noise. Subsection (6A) puts sound from traffic outside the definition, so the council can't serve a notice on a road. The remedy for a main road is glazing, orientation and which room you sleep in, all of which you choose when you buy.

Railways

We've written a whole post on buying next to a railway line, so only the outline here.

Two separate problems. Airborne noise, which the Defra rail map models, and ground-borne vibration, which it doesn't, and which is fixed at the track when the line is built rather than at the house. Freight runs on demand and outside the passenger peaks, so a weekday viewing tells you nothing about it. And section 122 of the Railways Act 1993 gives the operator statutory authority for running rolling stock on the network, which works as a defence to nuisance proceedings. The railway was there first, in law as well as in fact.

It's also common. Re-sampled in September 2026, about one active listing in five in and around London sits within 100 metres of a railway track, and one in ten within 50 metres.

Flight paths

Aircraft are the source people most often forget to check and the one the law does least about. Section 79(6) of the 1990 Act: the statutory nuisance provision "does not apply to noise caused by aircraft other than model aircraft". There's no council remedy and no neighbour to talk to.

What exists instead is measurement of a sort. The Civil Aviation Authority's Environmental Research and Consultancy Department produces the noise contours for Heathrow, Gatwick and Stansted using ANCON, "the UK civil aircraft noise contour model", and runs fixed noise monitors around those airports to validate it. The contour reports are published through the airports and the CAA, and they're the thing to look for: not "is it under a flight path", which most of London is, but which contour the postcode sits in and what the night-time figure is.

Two things to hold on to when you read one. A contour is an annual average, so a postcode "outside the 57 dB contour" can still have a plane over it every ninety seconds on the days the wind sends arrivals that way. And the World Health Organization's guidance for night noise, as its own fact sheet puts it, is "less than 40 dB(A) of annual average (Lnight) outside of bedrooms". Compare the airport's Lnight contour against that, not against silence.

Then visit under the approach, early morning, and count.

Pubs, venues and the neighbours

This is the one source with a legal route, and it's worth knowing how it works before you rely on it.

Statutory nuisance. Section 79(1)(g) of the Environmental Protection Act 1990 lists "noise emitted from premises so as to be prejudicial to health or a nuisance" as a statutory nuisance, and a council has a duty to investigate complaints from people living in its area. That covers a pub's garden, a venue's bass and the flat upstairs. It doesn't cover the road outside the pub, for the reason above.

Licensing. A pub or venue operates under a premises licence, and section 4 of the Licensing Act 2003 makes "the prevention of public nuisance" one of the four licensing objectives the council must promote. Section 51 lets "a responsible authority or any other person" apply for a review of a licence on grounds relevant to those objectives. So a resident can ask the council to look again at a pub's hours and conditions, though the council can reject a ground that's "frivolous, vexatious, or a repetition" of something already considered.

But the planning system expects the pub to have been there first. The National Planning Policy Framework, in its August 2026 edition, says at policy P4 that existing businesses "should not have unreasonable restrictions placed on their current or permitted operation as a result of development being approved after they were established", naming pubs and music venues specifically, and puts the burden on the developer as "the agent of change" to design in mitigation. If the flat you're viewing was built after the pub opened, the building was supposed to have been designed to cope with it. If it wasn't, that's a question about the building, not a complaint you'll win against the pub.

For all three, the honest test is the same. Ask the seller, in writing, whether they've complained to the council about noise from anywhere, and look at how the flat is built relative to the source.

What to do about it

Source by source, and then all of them at once.

Find the Defra road and rail maps for the postcode. The datasets are "Road Noise - All Metrics - England Round 4" and its rail equivalent, on environment.data.gov.uk, and they're what every noise-map website is showing you. Read the Lden and the Lnight, and remember both are 2022 models on a 10-metre grid.
If an airport is within twenty miles, read its contour report. Find which Lden and Lnight contour the postcode sits inside, and hold the night figure against the WHO's 40 dB. Then check whether the property is under an arrival or departure route, which the report's maps show and the average doesn't.
Visit three times, at the bad hours. A weekday at 8am for the road, a Friday at 11pm for the pub and the night buses, and a Sunday morning for what's left when everything else stops. Stand in the bedroom, not the kitchen.
Open the windows. Glazing is doing more work than you think. If it's quiet only with them shut, you're buying the glazing, and the seller's glazing may not be the one you'd have chosen.
For a railway, put your hand on the wall when a train passes. Vibration is the problem no map shows and no glazing fixes. Ask specifically about freight.
For a pub or venue, work out which was built first. If the flat's newer, ask what mitigation went in. If the pub's newer, the licensing review route exists and you can ask the council for the licence's hours and conditions.
Ask the seller in writing whether they've ever complained to the council about noise. A no is worth having in writing, and a yes is the most useful sentence in the whole purchase.

The honest summary

Every noise figure you can look up is a model or an average, so use it to decide which hours to visit rather than to decide the house. Roads are predictable and legally untouchable; railways are a vibration question the maps don't cover; aircraft have contours, measurements and no remedy; pubs have a legal route that works best when the pub is newer than you. Roughly a fifth of what's for sale in London sits near a big road and a fifth near a railway, so this isn't a niche worry.

The map tells you where to stand. Your ears, at eight in the morning and eleven at night, tell you whether to buy.

Worth reading next: buying next to a railway line, "near a station" is meaningless, what to measure instead, and how to read crime stats without scaring yourself.

This is general information, not legal advice. The datasets, planning policy and statutory provisions described here apply in England and are as at September 2026. Noise is subjective and varies by floor, aspect and glazing; visit at the hours that matter to you before you decide.