Cheaper rates will be offered to those who let properties with an energy performance rating of A to C. The products have a free valuation and £250 cashback.
The range is available for both purchase and remortgage and is also open to borrowers switching from another lender.
The remortgage options are at 60 and 75 per cent loan to value (LTV) with rates starting at 1.71 per cent for a two-year fixed at the lower tier. It offers free legals and has a fee of £995.
The product is 10 basis points cheaper than the mainstream alternative.
For purchases, there is a product at 75 per cent LTV with rates starting from 1.86 per cent for a two-year fixed mortgage with a £1,495 fee.
These products are available through intermediaries.
George Higginson, director of home buying and ownership at Bank of Ireland UK, said: “At Bank of Ireland for Intermediaries we want to play our part in responding to climate change. And by listening to our intermediary partners, we know that demand for green mortgages is growing. We want to make sure we respond to that demand by launching this exclusive buy-to-let mortgage range which recognises energy efficiencies.
“This green buy-to-let range is just the first step in our plans to launch more green initiatives in the months to come.”
Higginson added: “The bank has a commitment to be make its operations Net Zero by 2030 and so we want to make sure our products reflect that commitment, as well as help customers achieve their own personal energy efficient and sustainability goals.”