Dimension errors are some of the most common and expensive mistakes in construction drawings. One wrong number can ripple through the entire project. This guide covers the systematic checks that catch dimension problems before they cause trouble in the field.
Step 1: Check That Dimension Strings Add Up
This is the most basic check: do the parts equal the whole?
1
Add up the individual dimensions in each string. They should equal the overall dimension.2
Check both horizontal and vertical dimension strings3
Verify dimension strings on all four sides of floor plans4
Compare overall dimensions between plans and elevations5
Make sure building dimensions match site plan setbacksWatch Out For This
Designer changes one dimension but forgets to update the overall. Now the parts don't add up to the whole. But which number is actually correct?
Step 2: Cross-Check Between Different Views
The same dimension should match everywhere it shows up:
Floor Plan vs. Section
Room widths, corridor widths, wall thicknesses
Plan vs. Reflected Ceiling
Room dimensions, column locations
Plan vs. Enlarged Plan
All dimensions should match at different scales
Section vs. Elevation
Floor-to-floor heights, window sill heights
Step 3: Verify Critical Clearances
Some dimensions have to meet minimum requirements:
Door widths
32" clear for accessibility, 44" for egress corridors
Corridor widths
44" minimum for egress, often 60" for healthcare
Ceiling heights
7'-6" minimum for habitable rooms (varies by code)
Stair dimensions
Tread depth and riser height per code
Equipment clearances
Per manufacturer requirements and code
Step 4: Compare Against Schedules
Schedules have dimensions in them that need to match the drawings:
Door schedule widths should match door openings on plan Window schedule sizes should match elevations and plans Room finish schedule heights should match sections Equipment schedule dimensions should fit in the rooms shown Structural member sizes should match what's drawn Step 5: Verify Grid Line Spacing
The structural grid is the backbone of dimensional control:
Grid spacing should be consistent across all disciplines Grid dimensions should match between structural and architectural Column centerlines should align with grid intersections Dimensions to grid lines should be consistent Grid labels should match between plans and sections Step 6: When in Doubt, Check the Scale
If dimensions seem off, verify the scale:
Is the stated scale correct for the printed sheet size? Do scaled measurements match the noted dimensions? Are details at consistent scales within the same sheet? Was the PDF printed at the correct scale? Important
Never scale drawings in the field. If a dimension is missing, submit an RFI. Scaled dimensions aren't contractual and may be wrong because of printing issues.
Automate Dimension Verification
Checking every dimension string by hand is slow and it's easy to miss things. Articulate's AI can automatically verify that dimension strings add up and flag discrepancies across your drawings.
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