A23 road noise: how it affects nearby properties
The A23 is the principal London-to-Brighton route, running through south London and Surrey and on to the Sussex coast, with the M23 taking the fastest middle section. Dense housing lines its urban stretches through Croydon and Purley, while the Sussex sections towards Brighton pass through more open downland.
Traffic on the A23
High on the London and Surrey sections at 60,000–90,000 vehicles a day, feeding the M23 and the coast. Traffic volume, HGV proportion and speed all influence how much noise reaches nearby homes. As a major A-road, the A23 can carry motorway-level flows on its busiest sections while being much quieter elsewhere.
Areas near the A23
Passing through: Greater London · Surrey · West Sussex · Brighton and Hove.
Residential Croydon, Purley and Coulsdon sit close to the busy northern sections, often with existing barriers, while the approach to Brighton crosses the South Downs. AcoustaPlot reads Defra contours where they exist along the A23 and calculates a terrain-aware level elsewhere, distinguishing the exposed roadside homes from those sheltered by cutting or distance.
How AcoustaPLOT assesses A23 noise for your property
AcoustaPLOT geocodes your property, identifies the nearest carriageway of the A23, and estimates the daytime (Lden) and night-time (Lnight) levels at your facade — reading Defra's mapped value where available, or calculating it from DfT traffic data with real elevation data elsewhere.
Check my property near the A23 →
A23 noise: common questions
How much noise does the A23 make?
It depends on your distance from the carriageway, the traffic flow and the terrain in between. High on the London and Surrey sections at 60,000–90,000 vehicles a day, feeding the M23 and the coast AcoustaPLOT estimates the daytime and night-time level at your specific facade rather than quoting a single figure for the whole road.
Can a fence or barrier reduce A23 noise?
Often, yes. A well-placed barrier breaks the line of sight to the traffic and forces the sound to bend over the top, which costs it energy (insertion loss, per ISO 9613-2). Height, length and position all matter — the first two metres usually do most of the work.
Is a property near the A23 a bad buy?
Not necessarily — exposure varies enormously over a short distance, and terrain or existing screening can make a big difference. The only way to know is to check the exact address rather than the road as a whole.