A recessed entrance mat is the cleanest, most accessible threshold detail available — but it only works when the matwell, drainage and frame are detailed correctly from the start. This guide walks through the decisions that matter at spec time.
Match the recess depth to the profile
The matwell depth must equal the mat's profile height so the surface finishes flush with the adjacent floor. ALUEK profiles run 12, 17, 20 and 22 mm; the recess is formed to suit, with the substrate held to roughly ⅛ inch over 10 feet out of level.
Where a drainage pan is required for wet or exterior-adjacent doors, allow additional depth for the sloped tray and outlet.
Detail the frame and the transition
The matwell frame — aluminum, brass or stainless angle — retains the mat and forms the floor edge. Specify a flush transition so any change in level stays within the ¼-inch vertical / ½-inch beveled rule, keeping the threshold accessible.
Drop in the CSI 12 48 13 language
ALUEK publishes editable guide specs in CSI MasterFormat Section 12 48 13, Entrance Floor Mats and Frames, alongside CAD details and BIM-ready files — so the spec, the drawing and the model all agree.