Key Issue 1 - Chimney Flashcards
Why could the corbelled design not be left in-situ? What change had occurred to warrant extra works?
- Brickwork was deteriorating.
- Walls either side being removed.
- Thinner at bottom of breast [should be thicker].
Did you refer to any literature to assist in identifying any signs of failure?
BRE Good Repair Guide 3 - Repairing Damage to Brick and Block Walls.
Chimney: What was the cost and programme implication of each option?
- Approx £5,000 cheaper and 1 week less for Option 3.
How did you specify the brickwork repairs and the suspended ground floor works in the tender docs?
Brickwork: Referred to Good Repair Guide 3.
Floor: Structural engineer’s design portion.
Did you not allow for any unforeseen works in the budget?
Yes £10,000 contingency, but asbestos removal and lintels replacement used this up.
Who had design responsibility for the altered chimney works?
I did (CA), as it was not part of the original Contractor’s Design Portion.
[Structural engineer provided informal advice so their liability was limited].
[We did the design for most of the works – traditional procurement].
Chimney: Aside from cost variation, did this not require extension of time to the contract programme?
- Gained time by not doing the corbelled brick repairs.
- Other works continued while materials were ordered and installation was short (half a day).
KI 1: If there was a delay, would an EOT be warranted if requested? Why?
Yes, because it was a design change from the CA and not the contractor’s fault.
How did you cost the three different chimney rectification methods?
- Quote from principal contractor.
- Quote from one other contractor.
What RIBA stage was your project at when you had the chimney issue?
RIBA Stage 5 (Manufacturing and Construction).
When was the decision made to carry out the chimney support works?
3 weeks in.
How did you establish the time it would take to undertake these chimney works?
- Got a quote from the contractor who provided time implications.
- Reviewed the works involved and lead-in times for steel delivery to assess whether it seemed reasonable.
Who was responsible for the additional steels added in to support the chimney?
The structural engineer agreed to provide formal advice to change it to a box structure [instead of just one steel each side of the chimney at floor level].
How did you determine whether the chimney was loadbearing or non-loadbearing?
The structural engineer told us it was loadbearing.
Chimney: How did you verify the adequacy of the existing foundations to support additional loads from any new structural interventions?
- Part of the structural engineer’s works.
- Refurb works only - no significant weight was being added.
Chimney: How did you reassure the client about the structural safety of the final solution?
- Works built according to AD A.
- BCA signed off the works at the end of the project.
