Driveways, cabro paving and hardstanding
Cabro fails from underneath. The blocks are almost never the problem, and a driveway that has sunk into ruts was laid on a base that was too thin, badly compacted, or drained nowhere. The part that lasts is the part nobody sees.
Priced per square metre. What drives the cost is the base underneath, and the bigger the vehicles the thicker it goes.
The base is the job
Under the blocks there is hardcore, then a compacted murram or quarry dust layer, then a thin sand bed. Each layer has a thickness, and each has to be compacted in stages as it is laid. Skip that and the driveway looks correct for a season and then follows the wheel tracks down.
How thick the base goes depends on what will drive on it. A car is one thing. A loaded lorry delivering building materials or a tractor and trailer on a farm is another, and building for the car when the lorry is coming is a false economy that shows within a year.
Falls and edges
Paving has to be laid to a fall so that water runs off it somewhere sensible, and around here that means away from the house. Water sitting on a driveway gets under the blocks and takes the sand bed with it.
Edge restraint is the other thing that gets left out. Without a concrete kerb or haunching at the edges, the blocks migrate outwards under traffic and the whole field of paving loosens from the outside in.
Cabro or concrete
Cabro can be lifted and relaid, which matters if a service is going to be run under it later. It also handles ground movement better than a concrete slab, because it can settle a little without cracking.
A concrete apron is simpler and often better for a small area, a slope where blocks would creep, or a wash down area. We use both and will tell you which suits the spot.
Questions people ask
Why does cabro sink and go uneven?
Almost always the base. Either it was too thin for the traffic, or it was not compacted in layers, or water is getting under it because the paving has no fall and no edge restraint. The blocks themselves are rarely at fault, which is why relaying them on the same base does not fix it.
How thick should the base under cabro be?
It depends on what drives on it. A domestic driveway carrying cars needs less than an entrance a loaded lorry or a tractor uses. Tell us what will use it and we will build for that, because the cost of getting it wrong is relaying the whole area.
Is cabro better than a concrete driveway?
Cabro can be lifted and relaid if a pipe or cable has to go under it later, and it copes with slight ground movement without cracking. A concrete apron is often better for small areas, steep slopes and wash down bays. We use both.
Planning a driveway?
Tell us the plot and roughly what you have in mind. We will come and look, then give you an itemised figure.