Fitting floor beams is the placing of the beams (main and/or secondary beams) of an upper floor or roof structure on or into the load-bearing walls or frame, so that a joist layer is formed. It provides the load-bearing base on which the floor is then built up.
How are the beams fitted?
The beams are laid side by side at regular spacing:
- on the wall plate that rests on the wall, or
- in beam pockets or on a bearing in the masonry.
The beams sit at a fixed centre-to-centre spacing, so the load is distributed evenly. In older buildings, the beams were often built into the wall with their ends embedded in the masonry.
Key considerations
Several points matter when fitting floor beams:
- Sufficient bearing — the beam end must rest far enough on or into the wall to transfer the load safely.
- Ventilation of beam ends — ends embedded in masonry must be able to breathe to prevent wood rot.
- Correct beam size and spacing — these are matched to the load the floor must carry and to the span.
By correctly sizing and supporting the beams, a strong, stiff joist layer is created that carries the floor load down to the load-bearing walls.
Related terms
- Beam
- Joist layer
- Girder
- Wall plate
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