Family houses are under-occupied and only incentives to downsize can help improve the housing market – with a stamp duty cut being one of the most obvious.

That’s the thrust of a new report from the Centre for the Study of Financial Innovation, which says that if nothing is done there will be some 20m ‘surplus’ bedrooms by 2040, in homes occupied by the over-65s.

The growth in older households – over half of them one-person – is set to account for 36 per cent of the projected 3.7m increase in the number of UK households by 2040, it says.

The report says the current stamp duty regime “tends to jam up the housing market and can add significant costs to downsizing.”

It therefore calls on the government to ensure that so-called ‘last-time’ buyers are put on an equal footing with first time buyers with property purchases of up to £300,000 nil-banded for stamp duty.

The report also blames the housebuilding industry in part, saying there is a shortage of appropriate housing at affordable prices for downsizers; out also wants more independent financial guidance for older owners wishing to downsize.