Under the Vernon’s criteria change, mortgage terms can now extend beyond borrowers’ intended retirement age.

There is no maximum age for capital-and-repayment mortgages, while interest-only lending can be considered up to the age of 85 in some circumstances. The changes also create greater scope for reverse JBSP arrangements, where adult children pay for their parents’ mortgages.

The society has also removed the requirement for the property-owning borrower to demonstrate that they can afford at least 50% of the monthly mortgage payment.

Instead, affordability is assessed across all applicants.

The proposition is available for both purchases and remortgages. As with all Vernon mortgages, applications are considered individually and manually underwritten.

Brendan Crowshaw, head of mortgage and savings distribution at Vernon Building Society, said: “Family support can make a real difference to someone’s ability to buy a home, but the rules around how that support is structured can sometimes create unnecessary obstacles. We’ve enhanced our JBSP proposition to give brokers greater flexibility, with a more considered approach to mortgage terms and how the combined income of borrowers is assessed.”

Meanwhile, Loughborough Building Society has launched a new shared ownership remortgage product offering £1,000 cashback.

The two-year fixed-rate product is priced at 6.15%, with no application fee, a free valuation and £1,000 cashback payable seven days after completion.

The product is available to eligible borrowers looking to remortgage on a like-for-like basis, buy additional shares in their property through staircasing or raise funds for home improvements.

Ashley Pearson, head of intermediaries at Loughborough Building Society, said: “Shared ownership remains an important part of our lending proposition and we’re committed to developing products that recognise the different circumstances and needs of borrowers in this market.”