An overhanging stair tread is a stair tread one or both ends of which project beyond the line of the string (stringer) or riser, instead of finishing flush. It is a traditional detail with both visual and functional value.
Form
The size of the overhang varies:
- One side — on open-string stairs against a wall, the tread overhangs on the open side
- Both sides — on freestanding stairs, equal overhang on both sides
- Short overhang — 1 to 3 cm, a subtle detail
- Long overhang — up to 10 cm or more, sometimes with a chamfered or rounded edge
Sometimes the front nosing of a tread is also described as “overhanging” when it projects clearly beyond the riser.
Function
An overhanging tread offers several benefits:
- Visual character — gives the stair a rhythmic, layered appearance
- String protection — reduces wear on the stringer
- Foot support — in some designs the overhang gives extra grip for the foot
- Simplified joinery — easier to build in rustic timber stairs
Applications
Overhanging treads appear in:
- Farmhouse stairs — simple carpenter stairs with oak treads passing through the wall plate
- Industrial stairs — steel or timber stairs with continuous grating
- Designer stairs — modern stairs in which the overhang is deliberately emphasised
- Outdoor stairs — for faster water runoff along the sides
Points to consider
- Safety — a long overhang can be a trip hazard in narrow spaces
- Symmetry — on freestanding stairs left and right overhangs must match
- Fixing — the tread must be solidly anchored, as the overhang is unsupported
- Dimensions — for escape stairs follow building code limits for tread and rise
Related terms
- Tread
- Riser
- Stringer
- Riser board
- Nosing
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