Irish Permanent has introduced an "on demand" mortgage top up product called OnePlan. Homeowners will be able to get approval on borrowings of up to 75 per cent of the value of their home.

A distinguishing feature of OnePlan is that customers will not be obliged to withdraw the borrowings at the time of approval and once the borrowing limit is agreed, the amount approved may be withdrawn on demand, either all at once or on different occasions over a period of years.

A minimum drawdown of £15,000 on any occasion applies. Funds withdrawn under OnePlan attract the standard variable mortgage interest rate.