In Delaware buildings constructed with public funds, ramps that provide handicapped access must have a slope of less than 1 foot rise in 12 feet, according to Chapter 321 of the State of Delaware regulations. The maximum slope cannot be more than 8.33 percent, or 4 degrees 50 minutes.
For residential buildings not publicly funded, ramps must comply with the International Residential Code Section R311.6, notes New Castle County. Residential ramps must have a slope of 1 1/2 inch per foot or less. The Delaware requirements related to handicapped ramp slopes correspond with the federal American Disabilities Act Standards for accessible routes in Chapter Four, as detailed by the U.S. Access Board.