There has been a lot of talk, and many millions of words written, about the housing crisis these days (not least under this very masthead). There has also been much excitable chatter about the value of big data and maps. But so far, I think, there has not been much merging of the two topics to help us find effective solutions.

So ministers may have celebrated the increase in the number of homes in England given planning permission since the recession – but it is not the sheer quantity of homes that really matters if you are actually looking for one. What did you ask yourself the last time you moved? What you probably wanted to know is “is it near my job?” – or family, or partner’s job, or the kids’ school.

Yet that’s not always been factored into housing policy. We know that, in the 1960s, a lot of homes were built in the public (and private) sectors; and in the 1980s, a lot of homes were built in the private sector. But we also know that many of these homes weren’t well located at all: they were built instead in peripheral locations, where land was cheap, and the car (or taxi) was the key.

In 2012, the coalition government introduced a new planning policy for England. One key aim of the National Planning Policy Framework (NPPF) was to increase house building.

In 2014, the House of Commons communities select committee analysed the working of this policy. The committee recognised the strength of feeling the NPPF generates; but it considered it important that the outcomes of the NPPF were judged on the basis of evidence, not perceptions.

It concluded that it would therefore be helpful to have a small set of data monitoring a number of key outcomes – including, among other things, the success of the “town centre first” and “brownfield first” policies, and the volume and location of new house building

Since the location of development is a matter close to the hearts of urban planners, the Royal Town Planning Institute decided to take up this challenge. We commissioned Bilfinger GVA, one of the UK’s largest commercial property advisors, to map recent planning permissions for over 165,000 homes granted between 2012 and 2105 across twelve English city-regions – the largest study of its kind.

The resulting report shows exactly where new housing has been granted planning permission; the distribution and size of these developments; and their proximity to both major employment clusters and railway stations. And while these are by no means the only factors that should be considered, this type of analysis does help us to capture some of the spatial dimensions of sustainability. The aim of this research was to test a different way of monitoring the impact of planning – one which adds information to existing debates over quantity and affordability.

Our initial analysis found that, across the twelve city-regions, almost 75 per cent of the houses granted planning permission were within 10km of major employment opportunities, but only 13 per cent were within easy walking distance of a railway station. In other words, accessing those jobs meant having a car.

We’re just at the start of this process. We are going to be holding discussions with our members in the different city regions in coming months to flesh out the basic analysis. This will add local context to our analysis, consider the strengths and limitations of our approach, and look at how this research could be repeated in the future.

Below is our map for the Oxford City Region – an area which features frequently in discussions of house prices and rents, as well as discussions of the future of villages. So now you can tell exactly what is going on. And if you’re from Oxfordshire then hopefully you can be engaged in discussions of the future of the region.

In the meantime you can go on our website to see what we have found so far. The site includes more detailed maps for each of the 12 city regions, and also maps showing how housing permissions relate to jobs of different kinds.

After all, a home is all very well – but if you can’t easily get to work, how can you pay for it?

Richard Blyth is head of policy practice & research at the Royal Town Planning Institute.