A study by the RAC Foundation has revealed that 3.5 million homeowners have concreted over the front garden in the last 20 years - in total it means 7 million gardens have been sacrificed in favour of easier parking.

So why are gardens disappearing, and why is this a concern?

Tarmac

The RAC Foundation revealed that around 80% of Britain's 26 million homes were built with a front garden. However, the relentless march of concrete means that almost a third of these plots have been turned into drives. This equates to a space roughly equivalent to 100 Hyde Parks or 72 Olympic Parks.

Darren Johnson, chairman of the London Assembly's environment committee which produced these figures said: "If this was a real park that had been lost, there would be a huge public outcry."

Why?

The driving force behind the death of the front garden is car congestion. In 1950, there were two million cars. In 2011, there were 28.5 million - and it's getting increasingly difficult to find somewhere to park them all overnight. Not only are there more cars in than ever before, they are getting bigger. The Ford Escort of 1968 was five feet wide. Today's Ford Focus is six feet wide.

Even where properties have garages they are increasingly being used for storage of things other than vehicles or converted into extra accommodation. A third less cars are put away in a garage overnight than a decade ago.

And things are only going to get worse. Based on current rates of ownership, the rise in population alone is set to increase this figure to around 32 million cars in the next two decades.

Professor Stephen Glaister, director of the RAC Foundation, said: "Car ownership is set to keep on rising, but where are these vehicles going to go? Unless we want to see more streets clogged up and front gardens disappear then councils need to address the matter."

Other risks

However, the lack of parking isn't the only threat revealed by this study. There are three major issues that could hurt your pocket as the trend for paving over the lawn continues.

The death of the front garden is leading to flooding concerns. Increasingly the risk of flood is coming from surface water run off, rather than river water. Two-thirds of the homes flooded in summer 2007 were a result of this sort of flooding.

The problem comes because hard surfaces, such as tarmac drives stop heavy rain from sinking into the ground. It rushes to the nearest drain, which is soon overwhelmed, and the area floods. The more people who turn their front gardens into drives, the more hard surfaces cover the roads, and the bigger the risk.

In addition, it can contribute to subsidence. According to Neil Curling, Senior Subsidence Manager at Halifax Home Insurance: "Hard paving can cause severe subsidence as it reduces or stops rainfall getting into the ground."

And it can hit house prices. Johnson insists: "If lots of homeowners along a single street pave over their gardens, then the average house price
can drop."

What can you do?

The Royal Horticultural Society argues that it's possible to design a drive in the front garden, without losing the garden entirely. Homeowners could, for example, put down two stripes of gravel, with planting in between. This won't affect rainwater run-off, and will provide a place to park. If it is planted creatively, it can keep the garden looking attractive to homebuyers too.

But what do you think? Is there a real risk from the march of the tarmac, or is this just a necessary and sensible step for homeowners to take as cars clog city streets? Let us know in the comments.

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