Structural Audit is a Condition Survey of an existing building undertaken through a Structural Engineer/ Consultant with a view to understand if its Structural Stability has been adversely affected thereby causing Risk to the life of its occupants. The expert survey may be undertaken as per the Statutory Provisions or by the Own Choice of the Owner/s.


The Condition Survey consists of the following:

1. External Survey of walls, terrace, stilts, lobby and such other common areas

2. Internal Survey of tenements in the building such as Flats, Shops, Offices etc

3. Study of the Repair History and Feedback (problems faced) received from the occupants

4. Non-Destructive Testing of important structural elements of the building


Further action will depend on the findings documented in the Structural Audit Report and the Consultant’s Recommendations.

After construction, a building (structure) is handed over to its Owner. Thereafter, it becomes the responsibility of the owner to maintain it in a safe and habitable condition. Over a period of time, the structural condition of the building may deteriorate due to the following reasons:


1. Natural ageing, external seepage (rainwater) or internal seepage (flat to flat)

2. Additions, alterations, overloading or other misuse carried out by the Owners/ Occupiers

3. Poor maintenance, prolonged neglect of deterioration

4. Environmental factors such as saline weather, pollution & subsoil chemicals

5. Disasters such as fire, earthquake, blast


Therefore, Periodic Assessment, Maintenance and Repair of building is the key to enhance the Useful Life of your building!

The purpose of Structural Audit is to ensure Periodic Condition Survey of an existing building so that the Owners/ Occupiers become aware of its Structural Condition and they can take timely action to repair or strengthen it to maintain it in a habitable condition and to enhance its useful life.

Structural Audit came into effect by way of an Amendment to the Maharashtra Municipal Corporations and Municipal Councils Act, 2008 (Fifth Amendment dt. 07.02.2009). The following are the key points of the Amendment:

1. Structural Audit was defined as an “Examination by a Structural Engineer”

2. Purpose was defined as to check the “Fitness of Building for Human Habitation”

3. The Certificate of Fitness for Human Habitation was termed “Structural Stability Certificate”

4. Structural Audit is a Mandatory Provision and came into force with immediate effect


These amendments are reflected in the following Acts:

− Mumbai Municipal Corporation Act 1888 (Bombay ACT No. III) … Insertion of Section 353B

− Bombay Provincial Mun. Corporations Act, 1949

− City of Nagpur Corporation Act, 1948 and

− Maharashtra Municipal Councils, Nagar Panchayats & Industrial Townships Act, 1965

a) Structural Audit of buildings coming under the purview of Brihanmumbai Municipal Corporation (BMC):

These provisions are governed by Section 353B of the Mumbai Municipal Corporation Act, which are as under:

1. The First Structural Audit is to be undertaken when a Building is aged 30 years from the First Date of Assessment OR Issue of Completion/ Occupation Certificate OR Physical Occupation of at least 50% BUA OR Date of Water Connection, whichever is earlier.

2. Further Structural Audits to be undertaken every 10 Years thereafter.

3. Stability Certificate (Certificate of fitness of building for human habitation) must be submitted to BMC within 1 year.

4. The Consultant (Auditor) should be registered with BMC as a Structural Engineer.

5. BMC can direct the Owner to carry out Structural Audit earlier than specified depending on the Structural Condition of the building.

6. If Structural Audit or the corrective repair work is not carried out in time, BMC can charge a fine.


b) For buildings owned by Cooperative Housing Societies:

Model Bye-laws of Cooperative Housing Societies published by the Mumbai District Co-operative Housing Federation Ltd in August 2024, has provided for Structural Audit in Bye-law No. 76. The provisions are as under:

1. For a building ageing 15 to 30 years … once in 5 years

2. For a building ageing above 30 years … once in 3 years

For Societies which are in Municipal Corporation limits shall be conducted by approved Engineers from the Corporation panel. In case of other Societies, it shall be carried out by a Govt approved Structural Engineer.

Contents of the Structural Audit Report may be as under:

1. Building Description as a Structure, Repair History

2. Observations: Area/ Location wise

3. Distress Maps & Photographs/ Videos

4. Description of Repair Works to be undertaken

5. Stability Certificate/ Remarks:

- Whether Habitable, Type of Repair (Major/ Minor) & Urgency?

- Critical Remarks: Need of Evacuation, Propping, Safety Measures?

6. Proforma ‘B’ of BMC (Critical Observations & Recommendations)

7. Classification regarding Structural Stability : C1 or C2-A or C2-B or C3

8. NDT and/ or Repair Estimate, if undertaken


As per the guidelines provided by BMC, the Structural Condition/ Stability of the building may be classified as:

C1 - Unsafe Bldg: To be Vacated & Demolished Immediately

C2 - Needing Major Structural Repairs

- C2A – by Partially Vacating Dangerous Part

- C2B – without Vacating

C3 - Minor Repairs (No evacuation required)

Non-destructive Testing (NDT) may be undertaken depending on the structural condition of the building. Following is a list of NDT, which are commonly undertaken for RCC buildings and what they indicate:

1. Ultrasonic Pulse Velocity Test … Integrity/ Denseness of Concrete

2. Rebound Hammer Test … Surface Hardness of Concrete

3. Half Cell Potential Test … Probability of Corrosion

4. Carbonation Test … Depth of Carbonation of Concrete

5. Core Test … Compressive Strength of Concrete

6. Chemical Analysis … Chloride (Corrosion of Rebars), Sulphate (Deterioration of Concrete), pH (Alkalinity of Concrete)

7. Cement Aggregate Ratio … Indicative of Concrete Mix


However, which tests should be undertaken for a particular RCC structure and the no. of its testing points should be decided by the Consultant (Auditor).

They will be added progressively.