With time, every structure undergoes deterioration due to environmental exposure, change in usage, material ageing, and lack of maintenance. Before any renovation, vertical extension, change of occupancy, or even resale, it is essential to carry out a structural assessment to evaluate the safety and serviceability of an existing building through proper building structural inspection.
Structural assessment is not a formality—it is a technical and safety-driven exercise that must be performed by a qualified structural engineer following systematic steps, supported by a detailed structural assessment report.
1. Collection of Background Information
The assessment process begins with gathering all available data related to the structure as part of a systematic structural audit of buildings, such as:
- Original architectural and structural drawings
- Year of construction and design life considered
- Soil investigation reports, if available
- Past repair or retrofitting records
- Change in usage or additional loading over the years
This information helps the engineer understand the design intent and probable limitations of the structure before detailed building structural analysis.
2. Visual Inspection of the Structure
A detailed visual survey is conducted during structural assessment to identify visible signs of distress through proper building structural inspection, including:
- Cracks in beams, slabs, columns, and walls
- Corrosion of reinforcement and exposed steel
- Water seepage, dampness, and efflorescence
- Deflection or sagging of slabs and beams
- Settlement, tilting, or misalignment
Visual inspection often gives the first indication of structural health and helps decide the extent of further testing required during the structural audit of buildings.
3. Non-Destructive and Semi-Destructive Testing
To assess the in-situ strength and condition of materials during structural assessment, various non destructive testing for buildings are carried out:
Concrete Testing:
- Rebound Hammer Test
- Ultrasonic Pulse Velocity (UPV) Test
- Core Cutting Test (where required)
Steel Reinforcement Assessment:
- Cover meter survey
- Corrosion potential assessment
These tests provide reliable data on concrete quality, uniformity, and deterioration without major damage to the structure and support accurate building structural analysis.
4. Measurement and Verification of Structural Members
Actual sizes of structural members are measured on site as part of the structural assessment, including:
- Beam and column dimensions
- Slab thickness
- Reinforcement detailing (as far as detectable)
These are compared with available drawings or assumed standards of the construction period during building structural inspection. Any deviation or reduction due to damage is carefully noted for the structural assessment report.
5. Load Evaluation and Change of Usage Check
The engineer evaluates the structure during structural assessment by performing a detailed structural audit of buildings, including:
- Original design loads
- Current dead and live loads
- Additional loads due to new equipment, partitions, water tanks, or floor additions
- Impact of change in occupancy (residential to commercial, etc.)
Many old buildings become unsafe not because of poor construction, but due to unintended overloading identified through proper building structural analysis.
6. Structural Analysis and Code Compliance
Using collected data from structural assessment, the structure is analyzed using appropriate models for accurate building structural analysis. The analysis checks:
- Member stresses and load-carrying capacity
- Overall stability of the structure
- Compliance with current IS codes (IS 456, IS 1893, IS 875, etc.)
This step identifies overstressed or underperforming elements during professional building structural inspection.
7. Safety Evaluation and Structural Grading
Based on inspection, testing, and analysis carried out during structural assessment, the structure is categorized under a formal structural audit of buildings as:
- Structurally safe
- Safe with repairs
- Requires strengthening/retrofitting
- Structurally unsafe (urgent action required)
This grading helps owners and authorities make informed decisions supported by the structural assessment report.
8. Repair, Retrofitting, or Strengthening Recommendations
If required after structural assessment, the structural engineer suggests suitable measures based on building structural analysis, such as:
- Crack repairs and corrosion treatment
- Jacketing of beams or columns
- Carbon fibre wrapping
- Addition of RCC or steel members
- Seismic retrofitting for older buildings
All recommendations are backed by calculations, testing data, and non destructive testing for buildings results.
9. Final Structural Assessment Report
A comprehensive structural assessment report is prepared after completing the structural assessment, including:
- Observations and test results
- Structural analysis summary
- Safety conclusions
- Repair or retrofitting methodology
- Limitations and assumptions
This report serves as a technical and legal document for clients, municipal approvals, and future reference in structural audit of buildings.
Conclusion
Structural assessment of old buildings is a preventive engineering practice, not an expense. Timely structural assessment helps avoid structural failures, ensures the safety of occupants, and often saves significant repair costs in the long run through proper building structural inspection.
Never rely on assumptions or visual judgment alone.
A proper structural assessment today, supported by building structural analysis, can prevent irreversible damage tomorrow.
📌 When Should Structural Assessment Be Done?
- Before renovation or interior changes
- Before adding extra floors
- For buildings older than 25–30 years
- After earthquakes, fire, or flooding
- Before property purchase or resale