Above Grade by Jana L | Feb 25, 2022 | Glossary of Terms, Glossary of Terms -A, Uncategorized | 0 comments Refers to flooring installed above ground level, with a minimum of 18 inches of well-ventilated space available. Submit a Comment Cancel replyYour email address will not be published. Required fields are marked *Comment * Name * Email * Website Save my name, email, and website in this browser for the next time I comment.