The thickness of these treads put over your existing stairs may cause a trip hazard because you are adding a full inch which may cause stumbles. Different counties have codes regarding changes in the rise of steps in relation to each other and with the landings at the bottom and top of a stair case. Most likely this application will be outside of code. These treads are designed to replace not go over existing steps.
Please call our Sales Dept. (800) 476-0007 for pricing and availability of retro-fit treads that are designed to go over existing steps and will only add about 1/2" in height.
Thank you for your inquiry.
Answered on 9/26/2012 by cc-2