The average price for a flat or maisonette in Greater London is pound;205,000, according to the Land Registry. So it would take more than three NQTs, each borrowing three times their income, to get a mortgage. Even traditionally cheap places in London cost a fortune. The average cost of a flat in Southwark is pound;197,000; in Lambeth it’s pound;189,000; and in Hackney it’s pound;165,000.

Against these price tags, a teacher’s salary just doesn’t add up. And the extra few grand in the London allowance looks threadbare given the difference in living costs it’s meant to cover. The average terraced house in the north-west of England this year fetched pound;49,000.

Teachers starting work in the capital must live somewhere, so the Government, local authorities and housing associations are responding to the need for affordable homes for teachers. For instance, shared ownership schemes offer a mixture of renting and buying. These allow key workers such as teachers to buy a proportion of a house, then pay a low rent on the outstanding amount. In future years, they can buy more of the property. Another scheme is Key Homebuy, part of the Government’s Starter Home Initiative. This provides a loan of up to pound;35,000 towards a home. The repayment is made when the homebuyer sells up. This scheme excludes those in FE, non-state schools and some overseas teachers.

And there are local variations. For instance, Tower Homes, part of the London and Quadrant housing association, has a scheme for key workers in the London borough of Sutton that allows teachers to buy a 60 per cent share of a one or two-bedroom flat. They pay no rent on the remaining 40 per cent, but in later years can buy out the outstanding amount. It would be great if such schemes were not needed, but as a market crash or big pay rise seem unlikely, the problem looks set to run and run.

Starter Home Initiative, tel: 0800 015 3357. Websites: www.housing.odpm.gov.uk; www.keyhomebuy.com; www.lqgroup.org.uk (London and Quadrant)