When Toronto was created back in 1834, many building did not have indoor plumbing, electricity, natural gas, or communication lines. Insulation was haphazard if any. When we started to add those "features", sometimes damage would end up being done. That would mean tearing down and starting all over again.
Even furnaces would be monsters taking up most of the basements. The first furnaces would have been using coal, meaning a storage room in the basement for the coal. They would be replaced with oil burners, with an oil tank in the basement.
From
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From
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