An Post is to launch a "one-stop shop" for householders who are upgrading their homes to make them more energy efficient.
The scheme involves a package that includes cheap loans, having the work carried out for homeowners, and applying for the grant for the consumer.
The all-in-one approach will mean that those taking a loan from An Post will have the retro-fitting work carried out for them, project management looked after, and the grant- application process handled.
The Green Finance offer is being launched at a time when there is a national push to retro-fit up to 500,000 houses.
The scheme will enable householders to make environmentally responsible decisions when investing in their homes or when replacing petrol or diesel vehicles.
It comes under the State company's An Post Money brand, which already offers current accounts, personal loans and credit cards, with plans to offer mortgages and loans for small firms in the future. An Post has set up what it calls a Green Hub on its website, but consumers can also access it in 950 post offices.
The 'green loans' are issued by AvantCard for An Post with a rate of 4.9pc on amounts over €20,000.
Managing director of An Post Retail Debbie Byrne said this was a market-leading rate.
The loans are expected to be typically used for installing heat pumps, solar panels and wall insulation. The repayments on the loan can be stretched over 10 years.
Ms Byrne said: "This one-stop-shop approach will cover loan-only or full retro-fit services, from initial home assessments to completed works and a seamless Sustainable Energy Authority of Ireland (SEAI) grant application and payment process."
The offer also includes the provision of a survey.
An Post has partnered with the SEAI and energy company SSE Airtricity to carry out the works, and provide access to grants.
The SEAI administers grants, with up to €6,000 available for external-wall insulation on a detached house.