There has been much discussion about tiny homes meeting minimum size requirements for new homes in the Ontario Building Code (OBC). While multi-roomed homes have minimum room sizes, buildings, where rooms are combined (tiny homes), have a different requirement.
Despite Subsections 9.5.4 to 9.5.7 where living, dining, bedroom, and kitchen spaces are combined in a dwelling unit that contains sleeping accommodation for not more than two persons, the area of the combined spaces shall be not less than 13.5 m sq.Section 188.8.131.52 (1)
Within this space, the kitchen minimum areas shall be 3.7 m sq (184.108.40.206) and bedroom 4.2 m sq (220.127.116.11). This means that an 8.5 ft wide tiny home that is 19.25 ft long (outside dimensions) will meet the minimum OBC square footage requirements. The minimum ceiling height is 2100 mm or 6'10.6" heigh.
See the highlighted points in the building code section below for details: