High Road Noise
Significant traffic noise
High road noise is the top band on the strategic noise maps: modelled traffic noise over 75 dB Lden. Lden combines day, evening and night traffic noise into one annual figure, penalising the later hours. The maps are remade in rounds roughly every five years. Every UK nation produces this mapping, through a different body.
What This Means
Traffic will be constant rather than occasional, and audible indoors with the windows shut. Sleep and concentration are the first things to suffer at this level. A garden or balcony will be hard to use for quiet conversation. Secondary glazing can make the inside acceptable; nothing makes the garden quiet. If you later extend or build, the council may ask for a noise assessment. This does not normally affect mortgage approval, buildings insurance or resale.
Score Ranges
Low Noise
45 to 65 dB LdenTraffic noise is minimal and unlikely to intrude indoors or outdoors.
Medium Noise
65 to 75 dB LdenTraffic noise is noticeable but generally tolerable for most people.
High Noise
Over 75 dB LdenTraffic noise is significant and can affect sleep and outdoor use.
Practical Advice
- Get a quote for secondary or triple glazing on every room fronting the road before you agree a price.
- Visit at the evening rush hour to hear the worst case, then again at 3am.
- Check your nation's noise action plan to see whether this property lies in a priority noise area flagged for the highway authority to investigate.
- Ask your conveyancer to raise traffic noise in the pre-contract enquiries to the seller.
Additional Information
Important Areas are England's term. Scotland designates Candidate Noise Management Areas instead, and Wales and Northern Ireland run their own priority schemes. The collection linked here is England's; its strategic maps are round four, published in 2024 from 2021 traffic data.