For nurses, firefighters, police officers, teachers and paramedics – all of whom have their pay increases restricted by chancellor Gordon Brown's anti-inflation efforts – the problem is now becoming acute, Tim Crawford, group economist at Halifax, believes.
"Housing affordability continues to deteriorate for key workers across Great Britain and it is now clearly not a problem confined to the south of England," he said.
"Nurses face the most difficulties climbing onto the housing ladder but all key worker occupations are likely to struggle to purchase a house apart from in Scotland."
Only one per cent of towns in Britain passed the affordability calculation for British nurses.
Britain's ten most expensive towns are all located in the south-east, with Gerrards Cross, Weybridge and Sevenoaks all in the top five. London's boroughs of Kensington and Chelsea, Westminster and Camden all also feature.
"The government's key worker schemes are providing some relief but given recent trends there would clearly be benefits from broadening their reach," Mr Crawford added.
Halifax classifies towns as unaffordable when the house price: earnings ratio exceeds the first-time buyer average of 4.46 in all five key worker occupations.
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