What do the terms mean?
Props provide support, often vertically or at an angle. Needles are temporary beams inserted through existing walls to transfer load while an opening is formed or masonry is altered. A specialist system can combine these elements, but the equipment description is not a design for a particular house. [2]
Ask the team to explain what is supported at each stage, where that load goes and what has to be complete before the support can be removed. You do not need to choose the equipment yourself.
Temporary does not mean less important
HSE says temporary works need the same care as permanent works. Their management includes appropriate design, checking installation, authorising loading and coordinating dismantling. A temporary works coordinator is a recognised way to manage this, but HSE does not make that particular job title compulsory on every project. [3]
For a homeowner, the practical requirement is a named, competent person or team responsible for those activities. Avoid an appointment gap in which the permanent-works engineer assumes the builder has arranged the temporary design and the builder assumes the opposite.
Agree the plan before removing support
Request confirmation of these project arrangements:
- Who assesses the existing structure and specifies any necessary investigation?
- Who designs or selects the temporary system and checks its suitability?
- Who controls installation, inspection and changes on site?
- Who authorises load transfer and eventual removal?
The contractor's method should address the temporary stages, not merely repeat the finished structural drawing. Discuss access, the occupied parts of the home and how occupants will be kept away from the work.
Keep the work area controlled
HSE's public-protection guidance requires construction access to be managed and unauthorised people kept away from hazards. Openings, exposed edges and excavations need appropriate protection. Living at the property does not make it safe to pass through a propped work area whenever convenient. [4]
Ask for a defined route for occupants and a contact for urgent concerns. Do not move, adjust or remove a support to make room for storage, furniture or another trade.
Who carries the client duties?
Under CDM 2015, a domestic client's health-and-safety client duties normally pass to the contractor on a single-contractor project or the principal contractor where more than one contractor is involved. A principal designer can take those duties under a written agreement. Work commissioned as part of a business has different client arrangements. [5]
Confirm the actual appointments and keep the temporary-works records with the project documents. The spacing of props, sequence of wall removal and allowable unsupported spans require a competent assessment of the building and the proposed work.