Plaster protection that is more than 1" in thickness for fire-resistance must be reinforced with an additional layer of approved lath embedded at least how many inches from the outer surface?

The requirement for plaster protection that exceeds 1 inch in thickness and needs to be reinforced for fire-resistance is a vital aspect of building safety and compliance with fire codes. The reinforcement is necessary to ensure that the plaster can maintain its structural integrity in the event of a fire, helping to prevent the spread of flames and to protect the underlying materials and occupants.

When plaster is more than 1 inch thick, embedding an additional layer of approved lath at least 3/4 inches from the outer surface enhances the overall strength and fire-resistance properties of the plaster. The 3/4-inch distance is specified to ensure a proper balance between the thickness of plaster and the protective function of the lath, allowing enough plaster coverage to effectively protect the lath while still adhering to safety standards.

By embedding the lath at this specific distance, it ensures that the fire-resistive properties are optimized while providing adequate support to the plaster, thus fulfilling both structural and safety requirements.