Four clashing dimensions and a disputed revision on a fit-out
You are the lead carpenter on a two-storey commercial fit-out and have just received the drawings for release. Three problems appear on the same wall line:
- Architectural sheet A-02 (Rev C) shows a 900 mm x 2100 mm door opening in a 100 mm CHB wall. The door frame plus head clearance needs roughly 50 mm above the leaf.
- Structural sheet S-03 (also Rev C) shows a 250 mm x 400 mm beam running directly along that wall line, with its soffit 2350 mm above finished floor level.
- The partition schedule calls for 50 x 100 studs at 400 mm on centre for partitions over 2.7 m high - this wall is 3.0 m - but the general notes on A-02 say 600 mm on centre.
A dimension string of three bays at 1200 mm and two at 900 mm sums to 5400 mm, yet the overall dimension printed on the same line reads 5600 mm. The transmittal says Rev D is the current issue, but every sheet in the package is stamped Rev C.
1. In what order do you resolve these conflicts, and why that order?
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Stop layout on the affected wall line only; keep the crew productive elsewhere. Then work in this order:
- Revision status first. If the set is not the current revision, every other answer may be wasted effort. Compare the revision block with the transmittal, ask the consultant in writing which set governs, and mark the controlled copy. Never work from an unconfirmed set.
- Structural conflict second. The beam soffit at 2350 mm against a 2100 mm door plus frame leaves about 200 mm, which may or may not close - but if the door cannot fit, the layout of the wall, the frame order, and possibly the design change. Safety-critical and it stops fabrication.
- Dimensional closure third. A 200 mm discrepancy in the overall string means nothing downstream can be set out reliably; it must be resolved before any chalk line or formwork is placed.
- Stud spacing last. It affects the wall's performance (tiling, cabinetry fixing, straightness) but not structural safety, and can be resolved with a short written clarification.
The principle: resolve the item that invalidates everything else before the item that only affects one trade. Also verify the discrepancy by measuring on site - do not scale off the drawing and do not average two numbers.
2. Draft the content of the request for information (RFI) that covers these items.
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One RFI can cover the package, but each question is numbered separately so each can be answered and closed independently. Include:
- Header: project, RFI number, date, from, to, response required by date.
- References: drawing numbers and revisions, transmittal reference, gridline and level, so there is no ambiguity about location.
- Question 1 (revision): the transmittal lists Rev D but the set is stamped Rev C - confirm which revision governs and issue the current set.
- Question 2 (structure): S-03 shows the beam soffit at 2350 mm above FFL on the same line as the A-02 opening of 900 x 2100 plus frame and head clearance - confirm the opening can be formed as drawn, or issue a revised detail.
- Question 3 (dimensions): the bay string sums to 5400 mm but the overall dimension reads 5600 mm - confirm the correct overall dimension and bay sizes.
- Question 4 (studs): notes on A-02 give 600 mm on centre, the partition schedule gives 400 mm on centre for walls over 2.7 m; this wall is 3.0 m - confirm which governs.
- Your recommendation and impact: for example, propose 400 mm on centre as the conservative option, and state the cost/time effect of a late answer (frame order, wall setting out).
- Attachments: a marked-up sketch and site measurements.
Keep questions factual and answerable, not argumentative. One question per item is the difference between a fast reply and a three-week argument.
3. What do you do with the crew while the RFI is open, and what do you record?
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Keep the crew on work that cannot be invalidated: other wall lines, ceilings, areas unaffected by the beam and the dimension string. On the disputed wall, mark the line on the slab in chalk, install nothing, and treat it as a hold point. Do not pre-cut studs at either spacing - cut material to the wrong spacing and you have created waste and a second argument about who pays for it. Do not release the door frame for fabrication.
Record:
- The RFI number, date issued, and the date a response is required.
- The hold point in the daily site diary and in the weekly progress report.
- Photographs of the site measurement that shows the 200 mm discrepancy.
- Any verbal instruction, confirmed in writing within 24 hours (who said it, when, exactly what).
- The cost/time implication if the answer arrives late, logged as soon as it becomes apparent.
Explain to the crew in one sentence why they are waiting - 'the drawings disagree, so we are not building it twice' - because unexplained idleness damages morale and invites someone to guess. Guessing on a structural line is the single most expensive habit on a fit-out.