Sliding Door Sills and Flooring

This should never happen in new luxury home construction but I see it all the time. It takes a little planning, a little math, and a little caring to ensure sills are 3/16" or less above the flooring.

Sliding door sill risers vary in height depending on manufacturer and required design pressures to keep water out during wind driven rain events.

If you have a 2-5/8" sill riser with 1-1/2" of flooring (nominal), then you will be 1" below slab. This puts the top of a 120" door 119" above slab and 117-1/2" above finished flooring.

Aligning top of doors with top of floor to ceiling windows requires windows be shorter and that will depend on the frame size and what reveal the client wants at the floor. A 3/4" picture window frame has to be a LOT shorter than the door, a 1-3/4" storefront frame may only be 1" shorter than the doors.

Ideally this will be clearly defined in the shop drawings but at minimum the frame details reviewed with the architect and GC prior to shell construction.