Catch the errors that cost money —
before they reach the floor.
Automated shop drawing review for fabrication shops. Every sheet checked against 14 fabrication and engineering criteria. Fast turnaround — most reviews back within 24 hours. As low as $1 per sheet at scale.
What Plumb is actually catching in real packages.
A sample of findings from recent reviews. Each one would have hit the floor at full cost.
“Weld size missing on B/8 — would have stopped welder at fit-up.”
“Veneer direction not specified on three reception desk panels — would have triggered re-veneer.”
The errors are predictable. The cost isn't.
Every fabrication shop has the same conversation. A package goes through detailing, gets approved, hits the floor — and then the foreman sees it. A weld size missing on Sheet 8. A finish callout that contradicts the general note three sheets back. A dimension chain that doesn't close.
None of these errors should have made it to the shop. Each costs money. The worst part: they're predictable. The same categories of errors show up again and again because nobody has the time to systematically check every sheet against every criterion before fabrication starts.
| Error | Typical cost | What drives it |
|---|---|---|
Field RFI on a missed dimension | $500–$2,000 | Delays + engineer time + rework setup |
Re-cutting a wrong material allocation | $1,500–$8,000 | Scrap + reprocessing + missed sequence |
Wrong finish caught at install | $3,000–$25,000 | Rework, recoat, ship-back, schedule slip |
Missed PE-required item at permit | $5,000–$50,000+ | Permit hold, redesign, owner penalty |
Connection error at field-fit | $10,000–$100,000+ | Demobilize, re-fab, crane time |
Industry rule of thumb: rework on the floor costs 5–10× what catching the same error would have cost in the office. In the field, 10–50×.
Upload a PDF. Get back two files that drop into your workflow.
You upload
Drag your drawing PDF. Tell us tier and trade. ~2 minutes.
Plumb reviews
Every sheet, every category. Findings graded by severity. PE-required items isolated.
You receive
Marked-up PDF + Excel comments file. Typically in your inbox the same business day.
14 categories. Every sheet. Every package.
The criteria a senior reviewer would apply with a red pen — applied faster, more consistently, across every sheet.
Dimensional completeness
Every part dimensioned, chains close, tolerances stated.
Weld and joint definition
Weld size, type, length, finish, all-around vs intermittent.
Material specification
Grade, thickness, alloy, mill source, ASTM compliance.
Finish and coating callouts
Surface prep, primer, topcoat, dry film thickness, color.
Cross-sheet consistency
General notes vs detail notes vs schedules.
Bill of materials accuracy
Quantities match drawings, items numbered, no orphans.
Connection design clarity
Bolt type, grade, hole pattern, edge distance, slip-critical.
Fabrication sequence
Sub-assemblies defined, weldment hierarchy clear.
Shipping and handling
Pick points, weights, max dimensions, splice locations.
Field installation
Erection sequence, temporary bracing, anchor coordination.
Code and reference standards
Specs cited correctly, edition years, addenda.
Drawing legibility
Text size, line weights, conflicting notes, OCR accuracy.
Scope boundary
By-others items called out, owner-furnished material flagged.
Engineering review flags
Items requiring PE judgment isolated for licensed review.
↳ CUSTOM CATEGORIES AVAILABLE ON ENTERPRISE PLANS
Three tiers. Pick the depth your package needs.
Buildability
Documentation completeness for fabrication. Catches what stops the floor.
All trades, all packages
Engineering & Permit Submission
Tier 1 + readiness for engineering review and permit submittal. Catches what stops the permit.
Permit-bound work
Specification Compliance
Tier 2 + line-by-line compliance against your client's specifications.
Spec-driven contracts
Built for the way fabrication shops actually work.
Structural Steel
Beams, columns, connections, weldments.
- ·AISC connection geometry
- ·AWS weld symbols and procedures
- ·Camber and sweep callouts
- ·Bolt-hole patterns and edge distances
Architectural & Ornamental Metals
Aluminum, stainless, decorative.
- ·Alloy and temper specification
- ·Finish (mill, brushed, anodized, PVDF)
- ·Reveal and miter callouts
- ·Hardware and fastener exposure
Millwork & Carpentry
Custom casework, joinery, finish carpentry.
- ·AWI grade specification
- ·Veneer match and direction
- ·Edge band and hardware callouts
- ·Field-vs-shop scribe boundaries
Fiberglass & Composites
FRP, GFRC, mold-built parts.
- ·Laminate schedule and gel coat
- ·Mold parting line and seam locations
- ·Embed and pull-point specifications
- ·Cure schedule and post-cure callouts
Themed Entertainment / Scenic
Theme park, attraction, exhibit fab.
- ·Hardcoat thickness and texture
- ·Theming intent vs structural callouts
- ·Guest-reachable edge and finish requirements
- ·Show-action loading and durability notes
Carved Rockwork & Scenic Paint
Sculpted rockwork, hardcoat, scenic finish callouts.
- ·Carve depth and texture callouts
- ·Scenic paint schedule and topcoat
- ·UV/durability spec vs interior/exterior
- ·Wash, dry-brush, and detail finish layers
↳ MIXED-TRADE PACKAGES SUPPORTED
What QC costs your shop today vs. what it costs with Plumb.
Most shops don’t review every sheet — they spot-check, then absorb the cost when something slips through. Plumb’s value isn’t replacing reviewer hours you’re already spending; it’s catching the errors that currently hit the floor at full cost.
| Metric | Traditional QC | Plumb (Shop plan) |
|---|---|---|
| Cost of ONE error reaching the floor | $5,000–$50,000+ | Caught in the office, ~$0 |
| Annual sheets reviewed | 600 | 600 |
| Reviewer time per year | 350–400 hours | 0 hours |
| Labor cost @ $65/hr loaded | $22,750–$26,000 | $0 |
| Plumb subscription (annual) | — | $4,490 |
| Plumb overage (300 sheets @ $1) | — | $300 |
| Total annual cost | $22,750–$26,000 | $4,790 |
| Annual savings | — | $17,960–$21,210 |
| Senior staff freed up | 0 hours | 350–400 hrs |
If Plumb catches even one $5,000 error per year that would have reached the floor, the entire annual subscription pays for itself with $200 to spare.
Most shops catch that in the first two packages.
Five things that matter.
Built by fabricators, for fabricators
25 years between the shop floor and the engineering office. The findings sound like a senior shop reviewer because they were written by one.
Fast turnaround. Predictable.
Most reviews complete within several hours and typically land same business day. No human reviewer's schedule to wait on.
Price scales with sheet volume, not seats
Whole shop on one account. Detailers, PMs, foremen, estimators all share access.
Recurring patterns surface automatically
Plumb tracks repeat findings across your reviews. Fix the root cause in your detailing process, not just the symptom on each drawing.
Tier 3 specification compliance is real
Theme park, federal, healthcare, institutional. Your spec gets parsed once, lives in your private library, runs on every Tier 3 review. NDAs available.
How Plumb compares to the alternatives.
- Cost *
- $72–$1,800
- Turnaround
- When time allows
- Consistency
- Variable
- Drag
- Pulled from running the shop
- Cost *
- $90–$2,400
- Turnaround
- When time allows
- Consistency
- Variable
- Drag
- Pulled from winning new work
- Cost *
- $135–$3,300
- Turnaround
- When time allows
- Consistency
- High but expensive
- Drag
- Pulled from running the business
- Cost *
- $200–$5,000
- Turnaround
- 3–10 business days
- Consistency
- Variable
- Drag
- Zero impact
- Cost *
- $0
- Turnaround
- —
- Consistency
- —
- Drag
- Errors hit the floor at full cost
- Cost *
- $99–$2,000
- Turnaround
- ~24 hours typical
- Consistency
- Same criteria each package
- Drag
- Zero impact
* Cost ranges shown per package, based on typical 5–50 sheet packages and loaded hourly rates of $90–$200 for the relevant role.
Two files. Drop them straight into your existing workflow.
- • Bubble comments at every finding, color-coded by severity
- • PE-Review-Required findings marked with a [PE] badge
- • Trailing pages: summary stats, comment table, per-finding detail
- • Summary tab + Comments tab, one row per finding
- • Severity-color cells, frozen header, AutoFilter pre-applied
- + Documentation completeness and consistency review
- + Built by people with over 50 years of combined design-build, shop fabrication and engineering coordination experience
- + The criteria a senior reviewer would apply with a red pen — faster and more consistent
- −A code-compliance certification — we flag known code issues we spot, but we don't certify code compliance
- − A substitute for your PE or Engineer of Record
- − A drawing stamp or certification
Anything requiring engineering judgment is explicitly flagged as PE-Review-Required and isolated for review by your licensed design professional. That boundary is by design.
Questions shops ask before their first package.
01How accurate is the review?+
Plumb applies the same 14-category checklist to every sheet, every package. Consistency is the main accuracy gain over human spot-checks — where fatigue, time pressure, and the reviewer's familiarity with the project all create gaps that vary package to package.
We do not claim 100% capture, and we won't. No review process — human, automated, or both — catches every error in every drawing. Anyone claiming otherwise is overselling. What Plumb commits to is this:
- ·Every sheet gets a complete pass against all 14 categories.
- ·The same criteria get applied the same way, every time, regardless of package size or time of day.
- ·Findings are graded by severity so your team can triage instead of re-reviewing.
- ·Items requiring engineering judgment are isolated and flagged [PE] rather than guessed at.
What Plumb will not catch: errors that depend on tribal knowledge of your shop's specific practices, errors that require engineering calculations to identify, and errors in information that isn't present on the drawing itself. Those remain the responsibility of your team and your Engineer of Record.
The Express money-back guarantee exists for this reason. Send us a package you've already reviewed internally, compare what we found against what your team caught, and decide from there. If the review isn't useful, we refund you.
02What if Plumb misses something?+
Plumb is a documentation review service, not engineering. The Engineer of Record remains responsible for structural and code adequacy. See our Terms for full disclaimer.
03What file formats do you accept?+
PDF only, for now. Most CAD packages (Tekla, SolidWorks, AutoCAD, Revit, Inventor) export to PDF directly. Multi-sheet PDFs are fine.
04What counts as one "sheet"?+
One page in the submitted PDF. A 47-page PDF is 47 sheets, regardless of drawing size.
05What about my NDA / confidential drawings?+
Drawings are processed through Anthropic's API (no training on your data, per Anthropic's API terms) and stored on Supabase. Source files are deleted 30 days after upload. NDAs are available for Studio and Enterprise plans. Government-classified work is not supported.
06How fast is turnaround?+
Most reviews complete within several hours of upload. Our target for typical packages is delivery within 24 clock-hours, though very large or complex packages can take longer. Express orders carry a money-back guarantee if you want to validate timing on your own drawings first.
07Can I dispute a finding?+
Yes. Reply to your delivery email with the finding number and your reasoning. We'll review and reissue the deliverable if appropriate. Disputed findings inform our prompt and library improvements.
08Does it work with shop drawings exported from Tekla / SolidWorks / AutoCAD?+
Yes — Plumb reviews the PDF output, not the source CAD file, so the originating package doesn't matter as long as the PDF is text-searchable or high-resolution scanned.
09What if my drawings are hand sketches?+
Plumb works best on production shop drawings. Hand sketches may produce lower-quality findings due to OCR limits. Try one Express package to see if your sketch quality is sufficient.
10Can I switch tiers mid-month?+
Yes. Upgrades take effect immediately; downgrades take effect at the next billing period. Email hello@plumbreview.com to switch.
Still have questions? hello@plumbreview.com →
Ready to see what we'd find in your drawings?
Send us a 5–10 sheet package via Express ($99 one-time) or start a monthly subscription. Marked PDF + Excel typically back within 24 hours. Compare what we found against what your team caught. No sales call.