Driveways & Paving

Heave on Tarmac driveway laid over 16 years ago

Anonymous user 23/02/2024 - 2.57 PM

We have lived in our house about 16 years. We have a Tarmac driveway which was present when we moved in. Some years ago we noticed a crack across the driveway on the surface but this did not worry us. In the last few years the crack has raised. A few weeks ago we noticed we could see through the crack and to our horror there appears to be a hole of around 18 inches deep underneath. Underneath the Tarmac is concrete. We live in the South East. We have a flowering cherry in the front garden close to the crack. Our neighbours had two medium sized trees cut down about a year ago..not sure what the trees were but could be oak. We have sewer drains close by but these have been checked by our water authority and we are told they are in tact. Can anyone suggest what could be the cause of this heave and which type of surveyor/expert we should consult to find out what to do and what the cause is? Many thanks!