How we decide between hardboard and plywood
Hardboard is well suited to boards that are structurally sound but slightly uneven or gappy, where the main goal is a smooth surface rather than added stiffness. If the floor has genuine movement, spring or larger gaps, plywood is the more appropriate choice because it adds rigidity that hardboard simply can't offer at that thickness.
What we find when we lift old hardboard
- Boards that were never properly re-fixed before the hardboard went down, so movement continued underneath.
- Pins or staples that have worked loose over time and telegraph through thin floor coverings.
- Damp staining where hardboard has trapped moisture against boards near an external wall.
Finishes it suits, and where it falls short
Hardboard is a long-standing base for carpet and was traditionally used under sheet vinyl too. For LVT, particularly glue-down products, we'd generally favour plywood instead, since hardboard's thinness and surface characteristics aren't always as reliable a substrate for adhesive bonding over the long term.
Fife reality: older housing with layered flooring history
It's common in older Fife properties to lift an existing carpet and find hardboard already down over the original floorboards, sometimes from a renovation decades ago. We assess whether that layer is still sound and worth keeping, or whether it's better removed and replaced as part of the new fitting.
Fitting considerations
- Sheets are staggered to avoid aligning joints across the room.
- Conditioning sheets to the room's humidity before fixing reduces later movement.
- Proper pinning pattern avoids squeaks and loose spots developing later.