The commissioning walkdown: how to run one that actually produces evidence.

1. What a walkdown is for

A walkdown verifies that a subsystem physically matches its documentation and is fit to progress. It is normally the trigger for the punch list that gates mechanical completion, and it is usually attended by the client, so it is also the point where the project's record quality becomes visible to the customer.

2. Before the walk

1. Confirm the boundary. Everyone must be walking the same subsystem, with the boundary marked on the P&ID. Half of all walkdown disputes are boundary disputes.
2. Check readiness honestly. Walking a subsystem that is not ready wastes the client's day and costs credibility. Outstanding A-ITRs should be visible before you schedule it.
3. Print or load the tag list. The walk is against tags, not impressions.
4. Agree attendance. Construction, commissioning, the client and the relevant disciplines. Missing the electrical lead means an electrical re-walk.
5. Carry the previous punch. Open items in the same subsystem should be visible during the walk so they are not raised twice.

3. During the walk

Work systematically along the process flow rather than wandering by proximity. For each tag in scope, the checks are broadly consistent across disciplines:

• Installed as drawn — correct item, correct location, correct orientation.
• Accessible and operable — valves reachable, instruments readable, panels openable.
• Labelled — tag identification present, permanent and correct.
• Supported and protected — supports installed, insulation and lagging complete, no temporary works remaining.
• Complete — no missing bolts, blanks, gaskets, glands or terminations.
• Clean — construction debris, scaffolding and temporary supports removed.

Raise each finding at the item, with a photo and the tag, not from memory afterwards. This is the single biggest determinant of whether the walkdown produces usable punch — and the main reason walkdowns on tablet outperform paper.

4. After the walk

1. Categorise the findings — A, B or C, by a named authority rather than by whoever wrote them down. See punch categories.
2. Assign owners — every item gets a responsible contractor or discipline before the meeting ends.
3. Sign the walkdown record — the inspection itself is evidence and belongs in the dossier.
4. Publish the same day — punch raised digitally is visible immediately; punch typed up next week has already lost a week of correction time.

5. Avoiding the re-walk

A re-walk is the most expensive outcome, because it consumes the client's time twice. The three causes are almost always the same: the subsystem was not ready, the boundary was ambiguous, or the findings could not be actioned because they lacked a tag or a photo.

All three are preventable before the walk begins, and all three are cheaper to prevent than to repeat.