Temporary support is a construction-stage design problem. This page no longer publishes generic prop spacing, prop counts or removal times. Those details cannot be established from a beam length alone.
Establish the temporary load path
The design must address what is being supported, how forces reach adequate foundations or supporting construction, and how stability is maintained throughout the sequence. The permanent beam design does not automatically provide a temporary support design. See HSE guidance on structural stability and HSE temporary-works guidance.
Information to gather
Provide the existing construction, proposed opening, access, floor levels and any known concealed features. Identify where support equipment could bear and where occupants or other trades will be present. Unknown conditions should be resolved by the responsible competent people before relying on them.
Agree responsibilities in writing
Identify who designs the temporary works, selects equipment, installs it, inspects it and authorizes changes or removal. Keep the current design and sequence available on site. A change in equipment or support position must not be treated as an informal equivalent.
If site conditions differ from the design, pause the affected work and obtain direction from the responsible designer. Our calculators do not analyse props, needles, temporary bracing or the supporting floors.
Structural work requires a chartered structural engineer and the applicable Building Control approval. This educational article has not received an independent engineering review.