Submittals and shop drawings

The glulam beams and cross-laminated timber panels for Westgate were made in a factory 600 kilometres from site. Before the factory could cut a single piece, its engineers had to turn the structural drawings into fabrication drawings showing every panel, every connection, every screw pattern and every penetration for services. Those shop drawings went through Brightwater to Arden Moss and the structural engineer, Kessler Structural, who reviewed them and sent them back with comments. The first submission came back marked 'revise and resubmit'. The second came back 'reviewed as noted'. Only then did fabrication begin. Each review cycle took about two weeks, and the factory needed ten weeks after that to make and ship the first floor. That chain of dates, more than any single site activity, determined when the timber frame could start.

Submittals are the documents, samples and data that the contractor sends to the design team to show how it intends to carry out the design. They sit between the contract documents and the work: the designer says what is required, the submittal shows exactly what the contractor proposes to supply and install, and the designer's review confirms that it conforms to the design intent. This lesson covers the types of submittals, the process and the review actions, the responsibilities of each party, and how to plan submittals so that they never delay the work.

Types of submittals

Specifications list required submittals in each technical section, usually under a heading such as 'Action submittals' and 'Informational submittals'. Action submittals need the designer's review before the work proceeds. Informational submittals, such as test reports or installer qualifications, are filed for the record without a formal review action. The general procedures for all submittals are in Division 01, in the MasterFormat section 01 33 00 Submittal Procedures.

The submittal process

On Westgate, a submittal starts with the subcontractor or supplier who prepares it. It comes to Brightwater, where Hannah or the relevant project engineer checks it before it goes further. That check is not a formality. The contractor's review confirms that the submittal is complete, that field measurements and quantities have been checked, that it is coordinated with other trades, and that it matches the contract documents. Brightwater then stamps it, records it in the submittal log and sends it under a transmittal to Arden Moss, who reviews it or routes it to the responsible consultant.

CCDC 2 2020 requires the Contractor to review Shop Drawings before submitting them, to confirm that it has done so, and to point out in writing any deviations from the contract documents. The Consultant reviews them for general conformity with the design concept. The Contractor remains responsible for errors and omissions in its submittals and for meeting the contract documents.

Review actions

The designer returns each submittal with an action stamp. Wording varies from firm to firm, but the meanings are standard.

'Reviewed as noted' deserves care. Comments sometimes add requirements that were not in the contract documents, such as a heavier gauge or an extra coat. Hannah reads every comment against the specification. Where a comment changes the scope, she treats it like a changed RFI answer: Brightwater writes within the notice period to say it considers the comment a change, and does not simply absorb the cost.

Review does not transfer responsibility. A designer's review is a check of general conformity with the design intent, not a guarantee that dimensions, quantities, fabrication methods or coordination are correct. If a shop drawing contains an error that the designer misses, the contractor generally still bears the consequences, unless the error came from the contract documents or the deviation was specifically pointed out and accepted.

Deviations and substitutions

Sometimes a submittal departs from the contract documents: a different product, a changed detail, a revised dimension. The contractor must flag any deviation clearly, in writing, on the submittal itself and in the transmittal, so the designer can make a conscious decision. A deviation buried in the fine print of a 200-page product data package and not noticed by the reviewer is not accepted just because the package came back stamped.

Substitutions, where the contractor proposes a product other than the one specified, usually follow their own procedure set out in Division 01, with a request form, a comparison of the proposed and specified products, and a statement of any effect on cost, schedule and other work. Brightwater keeps substitutions out of the normal submittal stream so they are not mistaken for routine reviews.

The submittal register and schedule

At the start of Westgate, Jun built a submittal register by reading every specification section and listing each required submittal: about 640 items. Each item has a specification reference, type, responsible subcontractor, reviewer, and three key dates: when it must be submitted, when the review is due back, and when the material must be on site.

Westgate's Division 01 asks for a submittal schedule within 30 days of award, coordinated with the construction schedule, and allows the Consultant 10 working days for each review unless otherwise agreed. Brightwater's schedule links long-lead submittals directly to the activities they support.

The key is to work backwards from the date material is needed on site. For each item, Brightwater subtracts the delivery and fabrication time, then the review time, then a resubmittal allowance for items likely to need a second cycle, then the time the subcontractor needs to prepare the submittal. The result is the latest date preparation must start.

The calculation shows why long-lead submittals must start in the first weeks of a project, sometimes before the subcontract is even signed. On Westgate, Brightwater issued a letter of intent to the timber supplier so that shop drawing work could begin while the subcontract was finalized.

# Work back from required-on-site dates to latest submittal start dates
from datetime import date, timedelta
items = [  # name, on-site date, fabrication weeks, prep weeks, resubmit expected
    ('CLT panels level 2', date(2026, 8, 3), 10, 6, True),
    ('Curtain wall units', date(2026, 10, 5), 14, 5, True),
    ('Air handling units', date(2026, 11, 2), 16, 2, False),
    ('Door hardware', date(2027, 1, 11), 8, 3, False),
]
review, resub = 2, 3  # weeks
for name, need, fab, prep, again in items:
    weeks = fab + (resub if again else 0) + review + prep
    start = need - timedelta(weeks=weeks)
    print(f'{name:20} start by {start}  ({weeks} weeks before on-site)')

CLT panels level 2   start by 2026-03-09  (21 weeks before on-site)
Curtain wall units   start by 2026-04-20  (24 weeks before on-site)
Air handling units   start by 2026-06-15  (20 weeks before on-site)
Door hardware        start by 2026-10-12  (13 weeks before on-site)

Tracking and expediting

Once submittals are moving, the register becomes a tracking tool. Each week Hannah reviews items due for submission in the next three weeks, items with the designers past their review date, and items returned 'revise and resubmit' that have not yet come back. Like RFIs, the overdue list goes to the weekly meeting. Expediting continues after review: Brightwater tracks fabrication and delivery for long-lead items, with factory visits for the timber and curtain wall.

• Never release fabrication on a submittal that has not been returned with a review action allowing it.
• Distribute reviewed submittals to the field: the installing crew must build from the reviewed shop drawing, not the original contract drawing alone.
• Keep reviewed submittals in the record: they form part of the closeout documentation and are often needed for maintenance.
• Watch for submittals that sit with the subcontractor; slow preparation is as damaging as slow review.

Samples and mock-ups

Samples and mock-ups set standards that drawings cannot. Once approved, they become the benchmark for the work, so they must be labelled, photographed and kept safe until the work is accepted. On Westgate, the approved timber finish samples are stored in a locked cabinet in the site office, each tagged with its submittal number and approval date. The cladding mock-up was photographed from fixed points in daylight and kept on site until the cladding was complete; it was demolished only after Arden Moss confirmed in writing that it was no longer needed.

Electronic review and the record

Almost all Westgate submittals are reviewed electronically. Reviewers mark up PDFs in the platform, apply a digital action stamp and return them under an automatic transmittal. This is faster than paper, but it creates its own risks. Markups made in a reviewer's own software may not survive if the file is flattened or re-saved; comments added after the stamp may never be seen; and a consultant who reviews only the pages relevant to its discipline may leave other pages unreviewed without saying so. Brightwater asks every reviewer to stamp the cover sheet, list the pages reviewed, and return a single flattened PDF so the record shows exactly what came back and when. The platform keeps every version, so if a dispute arises about what a comment said on a given date, the answer is in the file history rather than in anyone's memory.