Laying a Steeply Sloping Driveway: A Case Study

In the mining valleys of South Wales it’s no surprise that laying driveways can be a bit tricky.

Challenging slopes and rock

Much of the housing stock is from the 19th and 20th century before cars were commonplace, so there’s often not enough space between properties to allow a drive wide enough for a modern car. Other options, like driveways in front gardens, can be ruled out because the older houses often open straight onto the street, or have very short, steep gardens.

Even those with long enough gardens often find that the gradient makes a driveway difficult and expensive, not to mention impossible. Then there is the problem of thin topsoil and the Welsh hills, granite or slate, just underneath, making excavation a real pain.

In fact, many of the most successful driveways added to period, Edwardian and Victorian properties in the valleys are those made by people lucky enough to have access to their back gardens from the street over and behind them. There’s at least then an option of building a terrace for a hardstanding and perhaps a garage.

Introducing the happy couple

The owners of the drive featured in this particular case study, Anne and Geraint Hughes*, were luckier than most, but still faced a tricky situation. Their property is an Edwardian semi-detached house in a village about fifteen miles north-east of Swansea.

“There isn’t really enough space between us and next door for one drive, let alone two,” said Geraint, “and the ground rises very steeply behind the houses, so a shared driveway to garages in each other’s gardens isn’t on.”

“We did think there was enough length in the front garden, but the slope is something like one in three,” he continued. “A couple of people further down the road have done tarmac drives in their front gardens, but we really wanted some that looked a bit less commercial.’

Research is vital

It was then a case of getting books out of the library and searching the internet.

“Don’t get me wrong,” he said, there was no way I was going to do it myself. But the more I feel I know about a subject the more I feel there’s less chance of a cowboy pulling the wool over my eyes.”

At this point in the interview Anne stoically kept a very obviously straight face and we guessed that this wasn’t the first time Geraint had buried himself in a quest for knowledge until finally being happy to part with his cash.

Surface comparisons

The long search for suitable driveway surfaces began. Gravel and other loose surfaces never even got a look in, for pretty obvious reasons, and concrete went the same way as tarmac.

For a steeply sloping drive concrete can be used very successfully but the laying and curing processes are slow. This is because wooden formers need to put down in small increments up the drive, to prevent the mix sliding too far down hill as it sets. But for many people, the Hughes included, the look of concrete was enough to put them off. Large concrete paving slabs were similarly discounted.

“To cut a long story short,” interjected Anne, speaking for almost the first time since setting down the tea and biscuits some three-quarters of an hour beforehand, “we decided on clay blocks. Then we just had to decide the colour and texture.”

Block paving

“That’s right,” Geraint said, “we felt the smaller blocks would cope better with any undulations, didn’t we love?”

“I knew it would be hard to get a completely flat surface,” he continued, “as the land slopes from side-to-side as well, and we’d just have to work with it. There was an old boy in the next street over who had it done but he wasn’t too happy as he didn’t think they’d haunched it well enough. Of course the blocks started moving after about five years.”

This showed the extent of Geraint’s research and he was dead right. Any block paving on a driveway should be well haunched to prevent the blocks pushing out sideways, or in Geraint and Anne’s case, in every direction.

Colour choice at last

“We picked as close as we could get to a Welsh blue granite,” Anne chipped in, “and I’m really pleased with the way it looks, but it’s not as slippery in the wet as the real thing.” She gazed out of the lounge window, which had been continuously lashed by the relentless rain since we’d arrived.

“Yes, that’s right,” said Geraint, “and we used flexible construction, not rigid.”

“Yes, the contractor wanted to use rigid,” Anne added.

“Now we’ve been through this,” said Geraint, “It might move if we use flexible construction but at least it’ll be easier to reset. With rigid it would have all broken in one go and the whole lot would have to be re-laid!”

We felt that we had intruded enough and beat a hasty but polite retreat. As we drove away the pristine driveway glistened in the early afternoon murk.

* names changed to protect the innocent. Well, Anne mostly.