Housing affordability for people with new mortgages reached its lowest level for 15 years in October as borrowers had to spend significantly more of their income on mortgage costs than they did at the start of this year.

The Council of Mortgage Lenders on Tuesday said first-time buyers spent 20.6 per cent of their income on mortgage interest in October, up from 20.4 per cent the previous month and 17.8 per cent in January.