How far should the clearance be from an obstruction in front of a lavatory?

The correct clearance from an obstruction in front of a lavatory is 21 inches. This dimension is established to ensure proper accessibility and usability of the lavatory space. Maintaining this clearance allows users to comfortably approach the sink, facilitating easy access for washing hands and performing other tasks.

Adequate clearance is especially important in residential and commercial settings, where design should accommodate various users, including those with mobility impairments. The 21-inch standard strike a balance between functionality and space efficiency.

Other possible clearances, while they may seem reasonable, do not align with the commonly accepted building codes and guidelines, which prioritize user accessibility and ergonomics in bathroom design.