General Window Requirements
All windows in the state of Florida must comply with general requirements. For instance, any window located at least 72 inches, or 6 feet, from ground level must have a sill located at least 24 inches from the floor below it. At least one window in each room must conform with egress requirements, meaning the window must qualify as a means of escape from the room. Further laws require the use of specific types of sealants and fasteners, minimum load-bearing resistance requirements and adherence to glass standards created by the American National Standards Institute, or ANSI.
A handful of provisions exist across Florida Building Codes specifically governing the installation of windows in block walls. For instance, you must seal all windows into masonry walls, such as block walls, with a sealant that meets standards set by either American Architectural Manufacturers Association, or AAMA, or ASTM, formerly the American Society for Testing and Materials. Furthermore, all windows installed in masonry walls require anchoring. For instance, a window with a wood shim or buck less than 1.5 inches thick requires a jamb clip or subframe system anchored in the surrounding masonry wall.
Approval and Inspection
You can install any window into an existing window opening or frame in the state of Florida without approval or permits so long as you make no structural alterations to the wall. If replacing an egress window, you must install a window no less than 95 percent the size of the previous window. When installing new window frames in a solid wall or building a new wall, a building inspector must approve your plans before installation. The window you install must be no more than ¼ inch smaller than or ½ inch larger on any side than approved by the building inspector. Upon installation, a building inspector must check and approve the new window. These stipulations first appeared in the 2007 edition of the code in response to the 2004 hurricane season.
Chapter 6 of the Florida Building Code Residential contains most provisions on windows, including masonry windows, though information also appear in chapters 3 and 7. Chapter 3 contains provisions on general building plans, which effect every aspect of a building, including windows. The Existing Building Code also contains information on the installation of windows, particularly the installation of new windows in existing frames, and the required processes for alterations to existing buildings. Find these provisions in chapters 6, 7 and 8 of the Existing Building section.