importance of Structural Audit

DAYANAND J. NENE
July 4, 2011
Dear Saketians,
Repairs to Society – Please READ these facts and ask yourselves questions..
For the past one year we all have been deliberating as to how to repair our society buildings, what should be the budget, whether it is affordable for our pockets etc. etc.
We all are attending General Body meetings and participating in discussions.
But let us ask ourselves a question: Are we really equipped with adequate knowledge to discuss the issues of repairs?
Can we or should we take decisions amounting to crores of rupees without getting satisfied about certain basic information?
I am again and again writing to all of you on the subject and providing you with some basic information or other, on the subject – only because you all should be well informed when you come to the General Body meetings and should be able to participate and take correct decisions.
And while doing so, I am not intending to offend, criticize or cast doubts or aspersions on anybody.
You are all aware that last year we conducted a STRUCTURAL AUDIT of our buildings.
Why was it conducted?
Structural Audit
Did you know that it is now mandatory for all co-operative housing societies, whose buildings are more than 15 years old to have a mandatory STRUCTURAL AUDIT carried out every 5th year to determine the existing life of the building's structure & the balance life of the structure?
The general health and performance of a building depends on its quality of maintenance. As a building grows old, ageing, use (or misuse) and exposure to the environment can affect the health of the building significantly.
Therefore, it is advisable to monitor it periodically by taking a professional opinion.
Structural Audit is a preliminary technical survey of a building to assess its general health as a civil engineering structure. It is usually initiated as the first step for repair. This is similar to the periodic health checkup recommended for older people.
When to do Structural Audit???
Model byelaw no. 77 specifies Structural Audit as a mandatory (necessary and binding) requirement. It stipulates that if the age of a building is 15 to 30 years, Structural Audit must be carried out once in 5 years and for buildings older than 30 years it should be carried out once in 3 years. You may, however, go for it even earlier if you suspect the condition of your building to be bad.
How is it carried out???
Structural Audit is commissioned by appointing a Consulting Structural Engineer registered with the Municipal Corporation of Greater Mumbai (MCGM or BMC) or in our case, TMC.
The Consultant carries out as a visual survey of the building covering its faces, stilts, staircase, terrace, flats, and ancillary structures such as pump room, compound wall, etc.
Repair history of the building and specific observations/ experiences of the members are also noted. Critical observations, probable causes of distress, remarks on structural health and recommendations for further action are given in the Structural Audit Report.

Why Structural Audit / Status Report???
• Exact details of distress at columns/beams/slabs (cover or core) 25%-50%-75% are known.
• Additional proof of sound structure before purchase or sale flat
• Members can understand the exact status/condition of their individual flat
• Easier to convince, to get co-operation and fund from members
• To produce if required by registrar or TMC or any other Govt. Dept
• Helps contractors to understand the exact nature of distress before touching the structure for repairs, so chances of increasing the work/cost is minimum.
• Even members can visualize the extent of repairs during work and can experience
• The condition of water distribution and water protection system also forms part of structural status report.
• Cost effective solutions and remedial measures will give full justice to your contributed amount. (Every single rupee of yours should be put to good use)
On the strength of authentic reports even after some years if problem arises you can contact consultants or contractor for rectifications.
Consultant’s involvement in repairs (proper planning-systematic/methodical repairs) improves the work –effectiveness by 95% .
STRUCTURAL AUDIT is a means of determining the existing defects present in the building's structure, the ways and means of rectifying these defects & the optimum cost required to rectify these defects.
The existing defects will determine the further life span of the building, and the STRUCTURAL AUDIT will also determine the further addition to the existing life span of the building after the defects pointed out in the structural audit have been rectified.
Sample Structural Audit
The buildings are visited and inspection carried out for:
A] STRUCTURAL DEFECTS & FAILURES.
B] SEEPAGE & LEAKAGE DEFECTS.
C] PLASTER DEFECTS.
D] PLUMBING DEFECTS & LEAKAGES
The entire report is subdivided into the following headings:
BRIEF SUMMARY.
IMPORTANT OBSERVATIONS & INFERENCES.
OTHER OBSERVATIONS & INFERENCES.
PROPOSED METHODS OF REPAIRS.
INTERNAL REPAIRS.
DEFECTS ON DRAWINGS.
DEFECTS IN TABULAR FORM.
GIVING OF FINAL SUMMATION WITH COST.
SUBMITTING BILL OF QUANTITIES
There are 2 distinct ways of conducting a STRUCTURAL AUDIT:
1. Simple visual survey + light hammer tapping to check the soundness of the structural members like columns & beams.
2. Complex visual survey + N.D.T. (Non Destructive Testing) using machines like the Rebound Hammer & the Ultrasonic Pulse Velocity test meter.
The entire building structure, right from the topmost point like the overhead water storage tank top, down to the underground water storage tank is checked internally as well as externally. Each and every flat is examined internally as well as externally to check for the following:
• STRUCTURAL DEFECTS
• WATERPROOFING DEFECTS
• PLASTER DEFECTS
• PLUMBING DEFECTS
• PAINTING DEFECTS
All the defects are noted in the form of a comparative chart & are also saved in the form of notations on the floor plan drawings of the building, Proper digital photographs of all the defects are also taken & preserved.
Based on these tools of observation, all the defects are then compiled into a proper B.O.Q. (Bill of Quantities) using a perfectly scientific methodology of selection in the preparation of the B.O.Q.
After the Structural Audit Report is received, it is decided what quantum of Repairs are required for any building.
Repairs to reinforced concrete structural members like columns, beams and slabs are becoming increasingly necessary, on account of the corrosion of reinforcement steel.
Corrosion leads to several other distressing aspects like cracking, spalling, delamination etc.
Repairs to these damages calls for special techniques and materials. Proper identification of the extent of repair is the first step. Removal of damaged plaster, concrete or mortar follows. At same time it is also essential to support or prop various elements, so that during repairs there is no possibility of unforeseen yielding of any structural elements.
REPAIR TYPES

(a) Minor
Minor repairs can generally be looked upon as those that do not require attending to the structural skeleton. Such repairs as water proofing, replastering, filling up non-structural cracks can be minor jobs.
(b) Major
Major repairs would need to tackle with the structural skeleton - at least attend to some of its members. This calls for an evaluation of the likely extent of repairs and strengthening measures required.
Based on the report received from the Structural Audit, depending on the amount of corrosion of reinforcement steel, it is determined whether the building will require major repairs.
We have got the Structural Audit done.
Now ask yourselves a question – how many of you know what is said in the Report?
How many of you have made an effort to find out, know or understand the nuances involved..??
As I have put earlier, the Structural Audit is the base of any repairs to a building.
Now I come to the Strut Report.
1. On perusing the Report, especially the Structural Audit part of it, I find that the recommendations made by them are very superfluous and surface floaters.
2. There are no concrete observations about the EXISTING status and ESTIMATED LIFE of each building.
3. All observations have been clubbed together and have been generalized. For example the report says while commenting on the Structural Status,
“Based on inspection of building from external side, internal flats and staircase from inside, it can be said that at present, the structural frame of the building of the building exhibits MODERATE degree of structural deterioration” – according to me, this comment indicates / confirms that the wear and tear is normal for a 20 year old structure.
4. Strut’s observations’ after the Core Test state “the above results show that the average compressive strength is of acceptable limits”. (This clearly means that the life cycle of our buildings is very much within the expected norms).
5. The report states that the strength of concrete is falling in Medium to Doubtful category.
6. It also states that reinforcement of steel is under corrosion and the probability of corrosion from 50% to90% was observed at all 96points tested at all buildings.
7. For healing Seperation Cracks between RCC members and wall panels-which is the root cause of leakage in the flat during monsoon – especially in everybody’s Living Rooms-, the report states that it should be treated using joint stitching treatment.
To sum up I have the following to say:
1. I fear that in spite of members contributing heavy amounts, we may still face problems after the work is done as again patch work plaster is being recommended, incomplete study by the present consultants, and a hurried approach towards the issue in the name of shortage of time.
2. Haste makes waste. I had said in my earlier communications to you also and I repeat again that it was impossible to start the Repair program before the onset of this monsoon – and I have been proved right. (It is a different part that nobody had agreed with me then.)
3. I am also afraid at the approach taken towards the cost of the project. Earlier it was in the vicinity of 10 crores. Then in the SGM, it was stated that 4.5 crores were required. Then after calling for tenders etc., I believe the figure is hovering around 6 crores. (I don’t understand how these figures are fluctuating so much?)
4. I also want to point out the lacunae in an EMI plan, which is one of the options. Suppose there is a delay (which is normal for a project of this magnitude), leading to costs escalation, this will trigger off a perpetual EMI trap for all members opting for EMIs - meaning members will have to contribute a huge sum every month for at least 4 to 5 years.
5. Let me explain my perception. The present contribution to Repair Fund @0.33 ps is fetching us appx. 20 lakhs per anum. If you recall that we had spent Rs. 1.90 crores in the year 2001 -2 on repairs and as per Strut’s report, the requirement is 10 crore in 2011 - at constant prices, it means that cost have increased 5 times in 10 years, which in other words means, we shall have to increase our contribution to Repair Fund by 5 times, making a 20 year old society’s outgoing at par with a modern day complex like Rustomjee.
Summing up, friends, please mull on all the facts. There are merits and demerits on both sides – if we do take a decision to undertake repairs in totality or otherwise.
So don’t decide emotionally or in haste. Let it take more time but ask for all information you want about the project. Think, consult, digest the information and then take your decision.
And let it be your decision – not because anybody, including me is telling you.
As is a saying in Marathi – ‘ Aikawe janache, pan karawe manache’- take everybody’s opinion but let the decision be yours.
Let our decision be collective, positive and in the overall interest of the society.
Regards,
Dayanand Nene