"Subfloor" means, for purposes of 35 Ill. Adm. Code 218 and 219, subflooring material over floor joists, including any load bearing joists. Subflooring is covered by a finish surface material.
Ill. Admin. Code tit. 35, § 211.6460
Added at 34 Ill. Reg. 14119, effective September 14, 2010