Shop Drawings and Submittals: The Approval Queue That Delays the Programme

The structural steel fabricator has a slot booked in the shop for the first week of next month. To hold it he needs the connection details approved, and he submitted them eighteen days ago.

The submittal went to the builder, who forwarded it to the architect, who passed it to the structural engineer, who has queried two connections and returned it. The clock restarts. The fabrication slot goes to somebody else’s job, and the next one is six weeks out. Nobody instructed a delay. Nobody did anything wrong, exactly.

What is a submittal in construction?

A submittal is anything the contractor or subcontractor formally submits to the design team for review and approval before the work is fabricated, ordered or installed. Shop drawings, product data, material samples, mock-ups, test reports and calculations are all submittals.[1]

The purpose is verification: confirming that what will actually be built matches what was specified, before money is committed to fabrication. That makes the submittal a checkpoint between design intent and physical reality.

It also makes it a lead time, and this is the part that gets left out of programmes. A submittal is not administrative overhead attached to a package. It is a duration sitting in front of every item that has to be made before it can be installed.

Shop drawings or submittals: what is the difference?

Shop drawings are a type of submittal, not a synonym for one.[4]

The distinction matters commercially because shop drawings carry a design coordination risk that a product data sheet does not. A returned tile sample costs a week. A returned steel connection detail costs a fabrication slot.

10 to 21 days

Typical contractual review period for shop drawings, with most specifications allowing two to three weeks per cycle

Industry standard review periods

How long does submittal review actually take?

The contractual review period is generally 10 to 21 days, with most specifications allowing two to three weeks.[2] That is the period for one cycle.

The number that matters is not the review period. It is the number of cycles.

Every rejection restarts the clock.[2] A submittal returned twice on a three-week review period has consumed nine weeks before a single item is fabricated, and none of it appears in the programme as a delay event because no instruction was issued.

Multiply that across dozens of trades and hundreds of submittals on a commercial build and the cumulative schedule impact becomes significant.[2] Research into shop drawing delay identifies the same cluster of causes seen on site: rework due to errors, suspension of work due to changes, delays in subcontractors’ work, coordination problems in the design drawings, and unrealistic schedules.[3]

Why the queue eats the programme

Four structural reasons, none of which are about anyone working slowly.

Sequential routing. Builder to architect to engineer to consultant, one at a time, each with their own queue. Where reviews could run in parallel they usually do not, because the routing is a chain rather than a distribution. Parallel routing and prioritising critical-path items are the two changes most often credited with compressing the cycle.[5]

Wrong reviewer. A submittal that lands with someone who cannot action it does not bounce back immediately. It sits, then gets forwarded, and the elapsed time is invisible because the register only records submitted and returned.

Vague review comments. “Revise and resubmit” without specifics guarantees another cycle. The contractor guesses at what was meant, and the guess is wrong often enough to add a third cycle.

Unclear revision tracking. Where nobody can say with certainty which revision is current, trades fabricate from superseded details. That is the same failure mode that makes working from the wrong drawing so expensive, arriving through a different door.

The common thread is that the register records the endpoints and nothing in between. Submitted and returned are captured. Where it actually sat, and for how long, is not.

9 weeks

Elapsed time for a submittal returned twice on a three-week review cycle, with no delay event recorded anywhere

Three cycles at 10 to 21 days

What good looks like

• Long-lead submittals are identified at procurement, not when the package starts, so the review duration is in the programme rather than discovered inside it

• Every submittal has a required-by date driven backwards from the fabrication or installation date, not just a submitted date

• Ageing is visible. A submittal sitting eleven days with a reviewer is flagged before it becomes twenty-one

• Reviews that can run in parallel do, rather than defaulting to a chain

• Review outcomes are specific enough to action in one pass, because a vague comment is a guaranteed extra cycle

• Revision status is unambiguous, so nobody fabricates from a superseded detail

• The approved submittal carries forward into the handover documentation rather than being re-collected at the end

• Submittals and RFIs are visible together, because a submittal held pending an RFI answer is two registers hiding one delay

That last point is the one most registers miss. A submittal waiting on an unanswered RFI looks stalled in one system and normal in the other.

The Australian context

A terminology note worth making, because it affects how teams search for this and how specifications are written.

“Submittal” is primarily North American usage, carried into Australia through international contractors and platforms like Procore. Australian specifications more often say technical submissions, shop drawing approvals, or simply list the items required for review under the relevant trade section. Under AS 4000 and similar general conditions, the obligation usually appears as a requirement to submit documents for the superintendent’s review within stated periods.

The practical consequence is that the same process runs under different names on different jobs, and the review durations are contractual rather than standardised. Two projects for the same client can carry different review periods.

The other Australian dimension is programme risk. With imported facade systems, lifts and specialist plant carrying long manufacturing and shipping lead times, a submittal cycle that runs three weeks longer than planned does not delay the item by three weeks. It can miss a production slot and delay it by months, which is precisely how construction schedules fail without any single dramatic event.

Where Plexa fits

Plexa runs submittals as a register with dates on both ends. Each item carries who it is with, how long it has been there, and the date it is required back to protect the fabrication or installation milestone.

Because submittals sit alongside RFIs, drawings and the programme in one platform, a submittal held up by an unanswered RFI is visible as one problem rather than two unrelated register entries. When a drawing revision is issued, the submittals raised against the superseded version are identifiable rather than assumed to be fine.

Ageing is the part that changes behaviour. A weekly view of what is sitting with whom, sorted by how long and by what it holds up, turns the submittal register from a record of the past into a list of this week’s calls. The eighteen-day item gets chased on day eight.

That steel fabricator does not need a faster reviewer. He needs the connection details to have been identified as long-lead at procurement, submitted six weeks earlier, and chased at day eight of the first cycle. The fabrication slot was always the constraint. The submittal queue was the only thing that could lose it.

Frequently asked questions

What is a submittal in construction? Anything the contractor or subcontractor formally submits to the design team for review before fabrication, ordering or installation. This includes shop drawings, product data, material samples, mock-ups, test reports and calculations.[1]

What is the difference between shop drawings and submittals? Shop drawings are one type of submittal. They are fabrication-level drawings prepared by the trade or fabricator showing exactly how an element will be made and installed. Other submittals include product data, samples, test certificates and calculations.[4]

How long does the shop drawing approval process take? The contractual review period is typically 10 to 21 days, with most specifications allowing two to three weeks per cycle. Because a rejection restarts the clock, a submittal returned twice can consume up to nine weeks in total.[2]

Why do submittals delay construction programmes? Sequential routing between reviewers, submittals landing with the wrong reviewer, review comments too vague to action in one pass, and unclear revision tracking. None of these register as delay events because no instruction is issued.[2][3]

Are submittals called something different in Australia? Often. “Submittal” is mainly North American usage. Australian specifications more commonly refer to technical submissions or shop drawing approvals, with the obligation set out as documents to be submitted for the superintendent’s review within stated periods.

Related reading

The register that most often holds a submittal hostage is covered in what a good RFI process actually looks like. The revision control that stops trades fabricating from superseded details is the subject of document control in construction. And for how these small delays compound, read why Australian construction schedules fail.

If you want to see which submittals are ageing and what they are holding up, book a 30-minute demo with the Plexa team.