Interior Floor Elevation Changes and Safety

Slope Tolerance

• Many home builders install floors made of materials such as wood and stone. These and other natural materials have minor imperfections that prevent them from being perfectly level. Building codes contain requirements that regulate how far off-level a floor can be. For instance, the building code of San Francisco allows a variance of 1/4 inch for every 10 feet of granite, marble, limestone, slate, wood and tile flooring. Your local building code establishes the requirements for houses in your area.

Flooring Transitions

• Changes in floor elevation can also occur when flooring transitions from one material to another -- for example, from a carpeted floor to a wood floor or from a wood floor to a vinyl floor. Building codes also contain tolerances for changes in elevation. The transition from one flooring material to another may be finished with a threshold that prevents someone walking through the house from tripping on a material edge. According to the building code for San Francisco, a threshold may extend 1/8 inch above the surface of the finished floor.

Drops in Elevation

• Openings in the floor that create a significant drop in elevation must be surrounded by adequate guardrails or barriers. Your local building code specifies the requirements for these guardrails. For example, the California building code regulates drops in elevation around stairways, ramps and balconies if the drop is 30 inches or more. The code also contains specifications for guardrails to prevent children from slipping through gaps in rails.

Other Hazards

• Uneven elevation is not the only unsafe floor condition that can cause people to trip. Other unsafe floor conditions include loose floorboards, protruding nail heads, cluttered floors, sagging floor supports and wet floors. You can avoid these conditions by picking up items left on the floor and cleaning up spills as soon as they occur. To avoid other hazards, inspect your floors regularly for sags or other defects, and take prompt action when you discover a problem that could make your floor unsafe.