Set project tolerances before steel or concrete alignment. Compare measurements against specs in seconds onsite. Download reports, avoid rework, and meet inspection targets easily.
| Height (mm) | Rule | Value | Allowable offset (mm) | Allowable angle (°) |
|---|---|---|---|---|
| 3,000 | Ratio | 1:500 | 6.00 | 0.1146 |
| 6,000 | Ratio | 1:750 | 8.00 | 0.0764 |
| 4,000 | mm per meter | 3.00 mm/m | 12.00 | 0.1719 |
| 8,000 | mm per meter | 2.00 mm/m | 16.00 | 0.1146 |
| 5,000 | Percent | 0.200% | 10.00 | 0.1146 |
Plumbness is the horizontal offset of a vertical element from its true line over the element height. Small deviations can amplify eccentricity, create secondary bending, and complicate connections, cladding, and MEP fit‑up. Defined limits let crews correct alignment early, protect load paths, and reduce costly rework. For tall cores and precast panels, minor offsets can affect crane set‑down and joint sealing.
Specifications commonly state limits as a ratio (1:N), a linear rate (mm per meter), or a percentage of height. Ratio rules scale with taller elements, linear rules are quick to verify with a tape, and percentage rules support performance‑based criteria. Some documents cap the offset with a limit, even when the rule scales. Always confirm which rule governs inspections and submittals.
The calculator converts the entered height to a consistent base unit, then computes allowable offset using the selected rule. It also expresses the same limit as an equivalent angle using arctan(offset ÷ height). If you enter a measured offset, it reports PASS/FAIL, the over‑limit amount, and an achieved ratio. Keep the measured value as a top‑of‑element offset taken at the same height you entered.
Use stable control: establish grid lines, verify benchmarks, and measure in low‑wind conditions when possible. Record the measurement point, height reference, instrument type, and face orientation. Take readings on two perpendicular faces to detect twist, and repeat after temporary bracing changes or final bolt tightening. For embedded plates, confirm that local bowing is not being mistaken for out‑of‑plumb.
Use allowable offset to plan shimming, brace adjustments, and connection tolerances before concrete set or final lock‑off. When results are near the limit, re‑check after load changes such as deck placement, grout curing, or formwork removal. Export CSV or PDF to attach a dated QA/QC record, photos, and sign‑offs. Consistent reporting improves tracking across floors and supports documentation for audits.
It is the horizontal offset between a vertical element’s top (or check point) and its true line over the measured height. It is usually recorded as an offset value and compared with a specified limit.
Use the rule stated in your contract documents or inspection checklist. If multiple limits appear, apply the most restrictive requirement or the one referenced for acceptance. This calculator supports ratio, mm per meter, and percent.
No. It is a quick compliance check and documentation helper. Final acceptance may require survey control, instrument calibration records, and formal reporting per your QA/QC plan.
Measure at the defined check height, commonly near the top of the element, from a verified control line or laser reference. Use consistent points (same face and elevation) across repeats to avoid mixing local bow with global lean.
Angle gives an intuitive sense of lean and helps compare different heights. It is computed using arctan(offset ÷ height). For small angles, the degree value will be very small, which is normal for tight tolerances.
You will still receive the allowable offset and angle for planning. Enter the measured offset later to get PASS/FAIL and the over‑limit amount, then export the report for your inspection record.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.