How to review shop drawings
Helonic is an AI construction drawing analysis platform for people review shop drawings during plan review.
A systematic approach to shop drawing review that catches errors before fabrication.
Shop drawings bridge the gap between design intent and actual fabrication. A thorough review process protects the project from costly field corrections and ensures the finished product matches the design. Here's how to review shop drawings effectively.
What Are Shop Drawings?
Shop drawings are detailed drawings prepared by contractors, subcontractors, suppliers, or manufacturers. They show:
- Exact dimensions for fabrication
- Material specifications and grades
- Connection details and hardware
- Finishes and coatings
- Fabrication and erection sequences
How do you verify submittal completeness?
Before diving into details, confirm the submittal package is complete.
- All sheets included per the submittal log
- Correct revision number and date
- Project name and number clearly marked
- Specification section referenced
- Contractor's review stamp present
- Product data sheets attached if required
Where do most shop drawing errors hide?
Most shop drawing errors hide in dimensions that do not match the contract documents.
- • Total width, height, depth
- • Opening sizes match plans
- • Clearances to adjacent work
- • Member sizes match specs
- • Spacing and layout correct
- • Hole locations and sizes
Look for dimensions that require field verification. If the shop drawing says "verify in field," ensure this is acceptable or request actual dimensions.
How do you verify materials and finishes?
Confirm materials and finishes match the project specifications.
- Material grade, ASTM A36 vs A992, etc.
- Finish type, Paint system, galvanizing, anodizing
- Color, Matches spec color code
- Thickness/gauge, Sheet metal, glass, panels
- Fire rating, Where applicable
Where do shop-drawing connection failures happen?
Connections are where shop-drawing failures usually show up.
Bolt sizes and grades, weld symbols and sizes, connection type matches structural drawings, embed plate sizes and anchor patterns
Anchor types and spacing, sealant joints and backing, thermal breaks, drainage provisions, movement accommodation
What do shop drawings reveal about other trades?
Shop drawings often reveal coordination conflicts with other trades.
- Does the steel framing clear the ductwork?
- Are electrical rough-in locations coordinated?
- Do penetrations align with structural openings?
- Is there clearance for maintenance access?
What do shop drawing approval stamps mean?
Approval stamps tell the fabricator whether to proceed, revise, or stop.
Proceed with fabrication. No changes required.
Proceed with fabrication incorporating marked corrections. No resubmittal needed.
Do not proceed. Corrections required before fabrication. Resubmit for review.
Fundamental problems exist. Complete redesign may be required. Resubmit.
What shop drawing errors show up most often?
The most common shop drawing errors are dimension mismatches, wrong materials, and missed coordination.
Fix: String dimensions and verify totals
Fix: Cross-reference specification sections
Fix: Verify all rated assemblies are labeled
Fix: Check scale bar and verify dimensions
Fix: Confirm current revision referenced
Fix: Require explicit deviation lists
Keep exploring
Related guides for submittal review and coordination.