New homes and the climate crisis

Sir, – Whether it’s achievable or not, Taoiseach Simon Harris’s promise to deliver 250,000 new homes between 2025 and 2030 seems bizarre, first in the context of Ireland’s obligation to reduce its CO2 emissions, and second in view of the number of vacant properties in the country.

The Massachusetts Institute of Technology (MIT) calculates that, depending on the size and type of house being built, the construction of one unit is responsible for between 15 and 100 tonnes of CO2 emissions. Assuming an average of 50 tonnes of CO2 emissions associated with building a new house in Ireland, the planned construction of 250,000 units would represent 12.5 million tonnes of CO2 emissions. But that figure covers only the houses themselves. Extra access roads and civic amenities such as supermarkets will also have to be built to serve the occupants of those houses. Road construction alone is a seriously high CO2 emitter, with the construction of one mile of single-lane road estimated (by the UK’s Institute of Civil Engineering) to be responsible for the emission of over 3,000 tonnes of CO2.

In 2022, the Central Statistics Office (CSO) calculated that Irish households, on average, consisted of 2.74 occupants, and that there were 166,000 vacant homes in the country, many of them vacant for several years. If occupied, those vacant homes could, theoretically, accommodate almost 700,000 people, while on the demand side, the CSO’s most recent estimate of the number of homeless came to 166,000.

It would, of course, be grossly simplistic to suggest that all the country’s vacant properties should be requisitioned to house the homeless, but there is a need for a much more imaginative and holistic approach to housing than just continuing to build new units. Bringing a vacant property up to a required standard is, in most cases, much more environmentally friendly in terms of CO2 emissions, and it doesn’t require the covering of new land with concrete. Assuming a requirement of 0.2 hectare per house (including road access, amenities, etc), 250,000 houses would cover about 500 square kilometres.