In this guide
Use this material to examine your own work. Confirm current requirements, forms and dates with IStructE before applying.
Provide a minimum of three critical details. Generic or simple typical details are explicitly unacceptable.
Which details are critical
A detail is critical when the scheme depends on it: when getting it wrong would change the design, and when it is where the load has to be resolved.
Ask which junctions in your scheme are doing something difficult:
- Where the load path changes direction or transfers. Transfer beams onto columns, hangers, changes of frame.
- Where the stability system connects. Bracing connections, shear wall to slab, core to frame.
- Where there is a discontinuity. Movement joints, major splices, changes of material.
- Where a cantilever is supported, including the back-span and any tie-down.
- Where the ground is involved. Retaining wall stems and bases, pile caps, ground beams.
- Anything unique to your scheme. If you proposed something unusual in 1a, its key junction is by definition critical.
A simply-supported beam-to-column bolted cleat is a typical detail, not a critical one. Drawing three of those is the failure mode the instructions are warning about.
How to draw one
Each detail wants: the members meeting, dimensioned; the connection medium (bolts, welds, reinforcement, bearing) indicated by type and rough size; a note of what it is transferring; and a label saying which part of the scheme it belongs to.
Annotate the force path through it. A note reading *"tie force 320 kN taken through the cleat into the slab reinforcement"* shows you understand what the detail is for, which is what is being marked.
On the supplementary paper this is a quarter of the marks
Part b is worth 20 of 80. That makes it proportionally the most valuable detailing section of any of the three papers, and it is worth practising specifically: selecting details from a scheme you have just invented, under time pressure.
Is this detail critical?
Ticked locally in this browser. If a detail satisfies none of these, it is a typical detail, and the instructions say those are not acceptable.
Drawing the details
Look for
- Dimension the members meeting at the junction
- Indicate the connection medium by type and rough size
- Annotate the force being transferred, with a magnitude if you have one
- Label which part of the scheme each detail belongs to
- Draw at least three
Watch for
- Submit a standard beam-to-column cleat as a critical detail
- Draw three variations of the same junction
- Detail reinforcement bar by bar: estimating standard is enough
- Leave a detail unlabelled and unplaced
- Run the section over on the supplementary paper, where it is worth a quarter of the marks
Official sources
Selected publisher pages were rechecked in September 2026. Other source records were last checked in July 2026. Open the latest official document before relying on a requirement.