What is the required thickness for a solid wood door between an attached garage and a dwelling unit?

The required thickness for a solid wood door between an attached garage and a dwelling unit is typically 1.75 inches, which is commonly rounded to 2 inches in practical terms. This requirement is rooted in fire safety standards, as these doors are meant to act as a barrier to slow the spread of fire and smoke from the garage to the living space. A solid door of sufficient thickness provides better insulation and resistance to fire than thinner doors.

Using a door of greater thickness enhances its structural integrity and improves its capability to withstand heat and reduce the transfer of flames and smoke during a fire event. This requirement aims to protect the occupants of the dwelling unit by providing a necessary level of safety. For instance, doors meeting the 1.75-inch thickness are often rated for fire protection, which is a crucial aspect of building codes and safety regulations.

While options that suggest lesser thicknesses do not meet the fire safety standards and would be insufficient for this critical application, the requirement for a thicker door is reinforced by fire codes and insurance standards, aiming to ensure maximum safety for residents.