Michael Lewis
Special to Ontario Construction News
Toronto will hold stakeholder and public consultations on proposed Official Plan amendments that aim to regulate how residential developments including so-called iceberg homes impact surrounding areas and the environment.
The consultation proposal adopted by the Planning and Housing Committee at its May 8 meeting directs staff to report back to the committee with final recommendations in the fourth quarter.
Iceberg homes, single-family detached residential buildings with a larger below grade footprint than their above grade footprint, often with multi-storey basements, are regulated by the same regulations as other detached houses, says a background report tabled with the proposed amendments. Current zoning regulations do not control below ground setbacks for small-scale residential buildings, such as detached houses with large below ground footprints.
But the report notes that iceberg homes can have a significant impact on the environment, climate and neighbouring properties, with the homes typically including additional or reinforced concrete, which has a higher amount of embodied carbon than other materials used for housing construction.
The iceberg design came into focus in 2021 when city council adopted a motion by then-Don Valley West, Ward 15 Coun. Jaye Robinson requesting a study on the emerging phenomenon in construction. The design trend has seen landowners build large, multi-story basements that extend significantly beyond the above-ground footprint, resembling a submerged iceberg. The design allows for expanded living space and luxury amenities below ground such as pools, gyms, or home theatres.
But building down also impacts soil permeability and erosion, results in mature tree injuries and removals, hampers drainage and stormwater management, and can lead to “collapsing neighbouring foundations,” Robinson, since deceased, said at the time.
At its meeting in December 2023, council, directed Planning and Parks, Forestry and Recreation to report on strategies related to protecting and enhancing tree canopy and green space, while also supporting infill housing growth.