A wooden floor consists of load-bearing joists (the joist layer) with a deck of boards or sheet material on top. Below are practical examples of how wooden floors are built up.
Examples of floor build-up
- Joist layer with floorboards — the classic upper floor: timber joists at centres, with tongue-and-groove floorboards over them. Common in older houses.
- Joist layer with a sheet floor — instead of separate boards, a deck of sheet material (plywood, OSB or chipboard) as a stable, flat sub-floor.
- Exposed-beam ceiling — the joist layer stays visible as a feature, with the floor deck acting as the ceiling of the storey below.
- Floating parquet floor — a finish layer of parquet or laminate on an underlay, kept clear of the walls to absorb movement.
Points of attention
- Joist spacing — the centre spacing and joist depth determine strength and stiffness; work out span and load in advance
- Deflection and bounce — a floor that is too weak feels springy; choose enough joist depth
- Ventilation — a ground floor over the crawl space must stay well ventilated against wood rot
- Movement of wood — let parquet and boards acclimatise first and leave an expansion gap at the edges
Related terms
- Wooden floors
- Joist layer
- Beam
- Parquet floor
- Sheet material
- Tongue and groove
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.