The federal government has announced $5.75 million in grants and loans to support "deep energy retrofits" in four residential buildings in Toronto and Hamilton.

Officials say the project, which is being funded through the Federation of Canadian Municipalities' Green Municipal Fund, will retrofit heating, cooling and lighting systems alongside other measures to reduce energy and water waste.

"I think we're all in agreement of why we need to improve the energy efficiency of buildings — it's the biggest, it's the fastest, it's the cheapest way to fight climate change," said Julia Langer, CEO of The Atmospheric Fund, which is leading the project.

According to a news release, the retrofits will reduce energy consumption by 40 per cent in these buildings, as well as cut energy bills for residents. The project includes measures like replacing baseboard heaters and window air conditioning units with all-in-one, energy efficient units, air sealing and weatherization on windows and doors, as well as the installation of solar panels and ground and air source heat pumps.

All-in-one heating and cooling units like this one are being installed in the building at 66 Walpole Ave., in the city's east end. (Chris Langenzarde/CBC)

The city says these upgrades are in line with Toronto's "TransformTO Climate Action Strategy," which includes a push to reduce greenhouse gas emissions in the city by 80 per cent by 2050.

"We're doing so much in the Toronto Community Housing communities," said Mayor John Tory at Monday morning's announcement. "It's never going to be enough, but [this is] a huge step forward."

"When you have homes and buildings accounting for 45 per cent of our greenhouse gas emissions, then you just know that initiatives like this one today — and then after that neighbourhood by neighbourhood, building by building across the city — [are] going to be something that is very important for the environment, but also very important for people."

A resident whose apartment has been retrofitted speaks with officials, including Mayor John Tory, at the project's announcement Monday morning. (Chris Langenzarde/CBC)

The buildings that will be renovated include one rental apartment building, one condo building and two low-income social housing buildings, representing nearly 800 households. Here's where they are located:

66 Walpole Avenue, Toronto

155 Wellesley Street E., Toronto

1 Palace Pier Court, Toronto

Sherwood Place, 25 Lynden Avenue, Dundas

The funding comes on the heels of a $1.3-billion funding infusion the federal government announced in April aimed at fixing Toronto's longstanding problems with crumbling community housing stock.