Posted: Mon Aug 16, 2004 10:33 pm
I have a tarmacked drive which is shared with a neighbour. The drive length is about 15 metres straight to my garage and dropping maybe a metre. There is a branch off to the neighbours’ garage and another to my front door. The whole area is about 180 square yards. The area has been subject to subsidence – both houses and garages have been underpinned c25 years ago. The drive is original about 32 years old. Unsurprisingly, it is littered with irregular cracks that seem to originate in the underlying concrete. In front of the neighbour’s garage there is clear evidence of subsidence in the drive, where it has dropped, probably, by a foot and recently a hole has appeared in the tarmac, adjacent to a soakaway, showing a 2 inch separation of the concrete joint and a hole underneath c18� deep and, at least, 3 foot wide.
One contractor proposes to cut out the centre of the subsided area (about 6 feet square - but more if necessary when he digs it out) and fill it, fill and seal the cracks then put on a new tack/wearing course.
A second contractor says this wouldn’t be satisfactory and proposes to dig the whole lot up and start again laying a sub-base of crushed concrete.
My questions are:
Is simply re-surfacing a false economy as presumably, the cracks – and there are a lot of them – will re-emerge?
Given the subsidence problem and the possibility of further movement under the drive, is tarmac a sensible approach anyway or should I go for blocks?
One contractor proposes to cut out the centre of the subsided area (about 6 feet square - but more if necessary when he digs it out) and fill it, fill and seal the cracks then put on a new tack/wearing course.
A second contractor says this wouldn’t be satisfactory and proposes to dig the whole lot up and start again laying a sub-base of crushed concrete.
My questions are:
Is simply re-surfacing a false economy as presumably, the cracks – and there are a lot of them – will re-emerge?
Given the subsidence problem and the possibility of further movement under the drive, is tarmac a sensible approach anyway or should I go for blocks?