M20 road noise: how it affects nearby properties
The M20 is the primary route through Kent to the Channel Tunnel and the Port of Dover via Folkestone, which gives it an unusually high and around-the-clock heavy goods vehicle share. Because HGVs generate more low-frequency noise that travels further and is harder to screen than car noise, the freight character of the M20 often makes night-time levels the deciding factor for nearby homes.
Traffic on the M20
Around 80,000–100,000 vehicles a day nearer Maidstone, with a heavy and sustained cross-Channel freight flow. Traffic volume, HGV proportion and speed all influence how much noise reaches nearby homes. As a motorway, the M20 carries sustained high-speed traffic day and night, so night-time levels are often the key concern.
Areas near the M20
Passing through: Kent.
Housing near Maidstone, Aylesford, Ashford and the Folkestone approaches sits close to the carriageway, and the Kent Downs create locally variable screening along the route. AcoustaPlot factors the M20's high HGV proportion into its calculation where Defra coverage is absent, and uses terrain data to reflect how the downland and cuttings shape the noise reaching a particular property.
How AcoustaPLOT assesses M20 noise for your property
AcoustaPLOT geocodes your property, identifies the nearest carriageway of the M20, 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 M20 →
M20 noise: common questions
How much noise does the M20 make?
It depends on your distance from the carriageway, the traffic flow and the terrain in between. Around 80,000–100,000 vehicles a day nearer Maidstone, with a heavy and sustained cross-Channel freight flow 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 M20 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 M20 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.