The bin lorry is the real client

You can design a cul-de-sac for the people who'll live there. You can design it for the architect, the planner, even the estate agent. But the vehicle that really decides whether your layout works is the one that turns up every other Tuesday at 7am.

The refuse lorry. Eleven-odd metres of steel, a turning circle like a cruise ship, and a driver who has seen every tight corner going.

We run swept path analysis on just about every layout we touch. For the uninitiated, that's software that drives a virtual vehicle round your road and draws where every bit of it goes. It is brutally honest. It doesn't care that the turning head looked fine on the masterplan. If the back end clips the kerb, the footway or someone's front garden, it shows you in bright colours.

Favourite moments over the years include:

• A turning head that worked perfectly, as long as the lorry reversed in from the other end of the street
• A 'shared surface' where the only surface not shared was the bit the lorry needed
• A beautiful tree, planted precisely where the overhang would remove it within a week

None of this is anybody being careless. Layouts go through a lot of hands, and it's easy for a few hundred millimetres to go missing along the way. That's exactly why we check early and check again once the landscaping and parking go on.

Our advice? Treat the bin lorry like the most important visitor to the site. Fire engines, delivery vans and the odd removal lorry tend to follow where it can go.

And if your turning head currently looks more like a parking space, we'd be happy to have a look….