Underlay choice for stairs specifically
- Stair-specific underlay is usually firmer and thinner than a domestic room underlay, to avoid excessive compression under concentrated foot pressure
- Underlay that's too soft on stairs can feel unstable underfoot and may accelerate nosing wear by allowing more movement
- Fitting no underlay at all on stairs, sometimes done to save on job cost, tends to shorten carpet life noticeably
- Underlay is normally fitted to each tread individually on stairs rather than run continuously like a flat floor


