Process deep-dive
Shop drawings and the custom fabrication process
Custom fabrication is a process. It starts with a quote and ends with an installed assembly, and the steps in between are predictable when the shop is set up correctly. This page walks through the actual workflow — what happens at each stage, who is involved, what gets produced, and how long each step takes.
The seven stages of a custom fabrication project
1. Inquiry and quote
Every project starts with an inquiry: a phone call, an email, a request through the contact form, or a forwarded set of architectural drawings. We ask for as much information as you have — drawings, photos, dimensions, finish preferences, schedule constraints. For most residential scopes, that is enough to produce a budgetary quote within 2–5 business days. For commercial scopes during the tender phase, we follow the GC's tender timeline and produce a formal quote.
The quote covers material, fabrication labour, finishing, delivery, and installation. It is broken down enough that you can see what you are paying for. For complex projects we sometimes provide a range pending final design decisions.
2. Project award and kickoff
Once the quote is accepted, we schedule a kickoff meeting (in person, by phone, or by video) to confirm scope, finalize specifications, and lock in any open design decisions. For commercial projects, this is also when we receive the architectural drawings, structural drawings, and any supplemental specifications that affect the fabrication.
3. Shop drawings
Shop drawings are the heart of the process. Our team produces detailed 3D models of every assembly, with full dimensioning, weld callouts, connection details, material callouts, and finish specifications. The 3D model is built to actual tolerances, which lets us verify that everything fits before we cut anything.
Shop drawings are submitted to the architect, structural engineer, and (on commercial projects) the GC for review. We expect markups and revisions — that is the point of the review. Most projects go through one or two rounds before final approval.
Timeline: 1–2 weeks for residential scopes, 2–4 weeks for commercial. Revisions add 1 week per round.
4. Material procurement
Once shop drawings are approved, we order materials. Most structural sections (HSS tubes, wide-flange beams, plate, channel) are stocked locally and arrive within a few days. Specialty materials — stainless plate, aluminum extrusions, custom hardware, hot-rolled sections in unusual sizes — can add 1–4 weeks of lead time. We confirm material availability before we commit to a fabrication schedule.
5. Fabrication
Fabrication happens in our Burnaby shop. The workflow:
- Material received, inspected, tagged, and tracked.
- Cutting — saw cuts on tube and bar stock, plasma or oxyfuel on plate, mitre cuts where specified.
- Forming — bending, rolling, and machining where required.
- Fit-up — assembly tacked together to verify dimensions and detail before final welding.
- Welding — by CWB-qualified welders following written welding procedures. Structural welds are inspected per CSA W47.1.
- Cleanup — grinding, weld finishing, surface preparation for the finish stage.
- QC — final dimensional check, weld inspection, and material traceability documentation.
Timeline: 2–6 weeks depending on scope. Simple residential railings run 2 weeks; complex commercial assemblies run 4–8.
6. Finishing
After fabrication is complete, the assembly goes to finishing. This is usually a separate facility (powder coat shop or galvanizing kettle) and adds 5–10 days to the timeline.
- Powder coat: 3–5 days for standard colors, longer for custom RAL.
- Hot-dip galvanizing: 5–7 days through a partner galvanizing facility in the Lower Mainland.
- Industrial paint systems: 5–10 days depending on the spec and number of coats.
- Stainless mechanical finishes: Done in shop as part of fabrication.
7. Delivery and installation
Finished assemblies are loaded, transported to site, and installed by our crews. For residential projects, installation is usually 1–3 days. For commercial projects, installation is coordinated with the GC's schedule and may run over multiple visits.
Crane picks are arranged for any assembly too heavy to set by hand. Field welding is handled by qualified welders. Field modifications are minimized — the goal is for everything to fit as fabricated, and our shop drawing process is designed to make that happen.
Closeout documentation (as-builts, weld test reports, material certifications, warranty information) is provided after installation for commercial scopes.
Why shop drawings matter so much
Shop drawings are where most fabrication projects succeed or fail. A shop that skips shop drawings, or produces them sloppily, will produce assemblies that don't fit, have wrong details, or fail to match the architectural intent. A shop that does shop drawings carefully will catch problems on paper before they become problems in steel.
Our shop drawings are detailed enough that the architect, engineer, and GC can review them and confirm everything is correct before fabrication starts. The reviewers' time is well spent because the cost of catching a problem at the drawing stage is roughly 1/100th the cost of catching it after fabrication.
Total project timelines
- Simple residential railing replacement: 4–6 weeks total
- Custom mono stringer staircase: 8–12 weeks total
- Floating staircase with embedded structure: 14–20 weeks total
- Commercial railing package (mid-rise residential): 12–16 weeks total
- Commercial egress stair system: 14–20 weeks total
- Structural steel package (residential addition): 6–10 weeks total
What a shop drawing actually shows
A shop drawing for a custom staircase, for example, would typically include:
- Plan view: Top-down layout showing stringer position, tread layout, landing geometry, and connection points
- Elevation views: Side views showing the stair profile, tread rises and runs, total rise and run, and any intermediate landings
- Section details: Cross-sections through the stringer showing section size, material callout, and weld details
- Connection details: Close-up drawings of how the stair connects to the building structure at top and bottom, with bolt sizes, plate thickness, and weld specifications
- Tread details: How each tread attaches to the stringer, bracket design, tread material callout, and fastener specifications
- Railing details: Post locations, railing profile, guard picket spacing, handrail height and mounting
- Finish schedule: Which parts get which finish, colour specifications, substrate preparation requirements
- Material list: Complete bill of materials for procurement
- Weld schedule: Which weld procedure is used on each joint, weld size, and inspection requirements
Related reading
For the CWB certification that backs the welding side of the process, see the CWB certified welding page. For how the process applies to working with architects and contractors, see the architect & contractor guide. For the materials used throughout the process, see the materials guide.
FAQs about shop drawings and process
What are shop drawings?
Shop drawings are the detailed fabrication drawings produced by the fabrication shop based on the architectural and structural drawings. They show every weld, every connection, every dimension, and every material — at the level of detail required to actually fabricate the assembly. Shop drawings are reviewed and approved by the architect, structural engineer, and (on commercial projects) the GC before fabrication starts.
Who pays for shop drawings?
On most projects, shop drawings are included in the fabrication shop's scope and folded into the project price. On larger commercial projects, they are sometimes a line item separately. Either way, the cost is part of doing the work — every custom fabrication project requires shop drawings, and they are not optional.
How long do shop drawings take?
For a typical residential staircase or railing scope, 1–2 weeks from project award to first submission. For commercial scopes, 2–4 weeks depending on complexity. Revisions add time — we typically go through one or two rounds of architect/engineer markups before final approval.
Why does the architect need to approve shop drawings?
Because shop drawings are the bridge between design intent and fabrication. The architect designed the project with specific aesthetic and functional intent. The fabrication shop interprets that intent into a buildable assembly. The shop drawing review is the architect's opportunity to confirm the interpretation is correct before the steel gets cut. Skipping or rushing this review is the most common cause of expensive rework on fabrication projects.
What software do you use for shop drawings?
We produce shop drawings in industry-standard 3D modeling software, exported to PDF and DWG formats for review. The 3D model is built to actual fabrication tolerances so we can verify connection details, detect interferences with adjacent structures, and confirm that everything fits before we cut anything.
What happens if I change my mind during the project?
Change requests are handled through a formal change order process. We document the requested change, price the impact on material, labour, and schedule, and submit it for approval. If approved, we update the shop drawings and proceed with the change. If not, we continue with the original scope. Changes requested during design or shop drawings are cheap and easy. Changes requested after fabrication has started are expensive because completed work may need to be scrapped. Changes after installation are the most expensive of all.
Can I see shop drawings before I commit to the project?
Usually not as part of the quoting phase — shop drawings represent significant engineering and drafting time, and we produce them after project award. What we can provide during quoting is a written scope description, reference photos or drawings of similar past work, and budgetary pricing. If you want to see detailed shop drawings before committing, we can sometimes produce them as a paid pre-design exercise.
How accurate are shop drawings?
Our shop drawings are built to the actual dimensional tolerances of fabrication — typically ±1–3 mm depending on the element. They show exact member sizes, weld specifications, finish callouts, connection details, and fastener callouts. When the fabricated assembly arrives on site, it should match the drawing to within fabrication tolerances. Site verification during shop drawings (measured dimensions of existing structure) helps ensure the drawings match the site as well as the design.
What is a submittal and why does it matter on commercial projects?
A submittal is the formal package of documentation a fabricator provides to the architect and GC for approval before fabrication. It typically includes shop drawings, material data sheets, welder qualifications, finish specifications, and any samples required. The architect reviews the submittal to confirm the fabricator has interpreted the design correctly, and marks up anything that needs to be changed. Once the submittal is stamped "approved" or "approved as noted," fabrication can proceed. Skipping or rushing the submittal process is one of the most common causes of expensive rework.
What is an RFI and how do you handle them?
An RFI (Request for Information) is a formal question from the fabricator to the design team about something unclear in the drawings or specifications. On commercial projects, RFIs are tracked through a formal log. We respond to incoming RFIs within 24–48 hours and we issue outgoing RFIs when we need clarification before proceeding. Fast, clear RFI handling is a differentiator between a well-run project and a stalled one.
Do you provide as-built drawings at project closeout?
Yes. For commercial projects, we provide as-built drawings that reflect any field changes, modifications, or adjustments made during installation. These become part of the building's record set. For residential projects, as-builts are provided on request — most residential projects don't formally require them, but homeowners sometimes want them for future reference or resale documentation.
How do field measurements get incorporated into shop drawings?
For projects where dimensional accuracy is critical (retrofits, connecting to existing structure, fitting into tight tolerances), we do a site visit to measure existing conditions before finalizing shop drawings. The measurements are incorporated into the drawings so the fabricated assembly matches the actual site. For new construction projects where the structure doesn't exist yet, we work from the architect's drawings and coordinate with the framer to confirm dimensions during construction.
What happens if the architect rejects the shop drawings?
Rejection is rare if we've done the drawings carefully, but when it happens we go back to the drawings with the architect's markups and revise. Common reasons for rejection: the finish doesn't match the specified colour, the structural detail doesn't match the engineer's callout, or the architect wants a visual change they didn't specify clearly the first time. Revisions usually take 3–5 business days. We don't proceed to fabrication until the drawings are formally approved.
Get in touch
Need a fabrication quote?
Send drawings, photos, or even a rough description. We will review what you have and follow up with a quote or a conversation about next steps.