The green mortgage product rewards existing borrowers who want to take additional borrowing to fund home improvements with a lower interest rate.
To be eligible, borrowers must intend to use at least half of the funds for one or more environmentally friendly home improvements.
The GoGreen further advance product options include a five-year discount at 1.49 per cent which is from 0-60 per cent loan to value (LTV) and another five-year discount at 1.59 per cent, from 0-75 per cent LTV.
The minimum and maximum loan amounts are from £2,500 to £39,999.
This product was developed in response to the chancellor’s announcement of a £5,000 grant to homeowners looking to make greener renovations to their homes.
Karen Smith, sales manager at Newbury Building Society, said: “More of us are becoming increasingly aware of our impact on the environment and are seeking ways to reduce our carbon footprint.
“One way of doing this is to encourage homeowners to make energy efficient changes to pre-existing homes, not just new-build investments.”
She added: “Our GoGreen further advance incentivises existing borrowers to improve their energy performance certificate to help combat climate change.”