Section 375.11. One-hour fire-resistive ceiling.

  A one-hour fire-resistive ceiling shall be constructed of not less than 1 5 / 8 inch joists, spaced not more than 16 inches center to center, protected on the under side by metal or wire lath and 3 / 4 inch of gypsum or Portland cement plaster or by 3 / 8 inch perforated gypsum lath and 1 / 2 inch of gypsum plaster, the joints of the lath to be reinforced with 3 inch wide strips of metal lath. Other materials and methods of construction having an equivalent fire-resistive rating may be used if approved by the department, as specified under s. Ind 50.12 , 1956 .

1-2-56 ; renum. and am., Register, September, 1974, No. 225 , eff. 10-1-74; corrections made under s. 13.93 (2m) (b) 4. and 7., Stats., Register, June, 1995, No. 474 .