Every dwelling unit must have at least one habitable room of what minimum size?

The minimum size of a habitable room in a dwelling unit is set at 70 square feet. This requirement ensures that the space is sufficient for practical living purposes, providing adequate room for furniture and movement. The designation of a habitable room includes areas such as living rooms, bedrooms, and similar spaces intended for everyday use. By establishing a minimum square footage, building codes aim to ensure comfort and livability, as smaller areas can negatively influence the quality of life within a dwelling. This guideline is essential for maintaining standards in residential construction, and it helps in promoting safe and adequate living conditions for inhabitants.