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Vandana Ramnani vandana.ramnani@hindustantimes.com
India has five tall buildings,the highest being the 117-sto-
rey World One project in
Mumbai, that have made itto the recently released Council
on Tall Buildings and UrbanHabitats list of 100 tallest
buildings under construction
in the world 2013. The countryhas over 100 tall structures that
are ready and another 200 are
in the pipeline.What is alarming is that
despite the country not having
a tall buildings code, both Noidaand Gurgaon, which are part
of the high-risk seismic zone4, are building 50-storey-plus
structures, and Delhis Master
Plan 2021 focuses on verticaldevelopment as the only way
forward.
Structural and seismicengineering experts lay great
emphasis on the fact that a
specialised tall buildings codeis the need of the hour. In its
absence, most tall projects in the
country are being constructedin consultation with interna-
tional experts who h ave workedon similar projects abroad.
While theres nothing wrong
in following international bestpractices or codes, nobody can
be held accountable if an even-
tuality like an earthquake wereto occur and destroy or damage
buildings, say experts.
They also point out that mostbuilding codes in the country
are almost a decade-old or moreand applicable to structures of
up to only nine to 10 storeys.There are also no mandatory
specialised provisions for wind
or earthquake loads that are
prerequisites for construct-ing tall structures. What this
means is that in the eventuality
of an earthquake in the zone3 or zone 4 areas, nobody can
be held accountable if there is
damage to the structures, asthese have been built according
to the existing code. Developersattempting to build structures
above 50 storeys should know
that the outcome will be similarto an automobile manufacturer
attempting to make aircraft, the
experts warn.Mumbai has tried to make
up for the absence of a tall
buildings code by setting upa tall buildings committee
which reviews the projects. TheNational Management Disaster
Authority (NDMA) had also pro-posed the setting up of a Delhi
Tall Buildings Council to the
Delhi government in 2011. That,
at best, can only be a stop-gaparrangement. The need of the
hour is a tall buildings code,
say experts.Rama Raman, CEO, Noida
Authority, agrees. As of now,
developers planning to buildtall structures are expected
to submit no-objection certifi-cates with the auth ority. These
include clearances from the
airport authorities and thefire department. We, too, may
consider setting up a council
Continued on page 12
Related stories on page 12
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N E W D E L H I , S A T U R D AY , J A N U A R Y 2 5 , 2 0 1 4 , 1 4 P A G E S w w w . h i n d u s t a n t i m e s . c o m
takefive
what are the codes all about?
* The rates, in rupees, are indicative only Source: Makaan.com
RENT AND CAPITAL RATESFARIDABAD (RESIDENTIAL)
Location Rental (per sq ft*) Capital (per sq ft*)
Ashoka Enclave 9-11 6000-10000
Badkal Lake 8-10 4000-9000
BPTP 7-14 3000-4000
Charmwood Village 18-20 9000-11000
Green Field 10-13 3000-6000
Nahar Par 8-10 3000-4000
NIT 7-11 4000-6000
Palwal 5-10 2000-3000
Codes versus guidelines:Codes are legallyenforceable but guidelines are for designers and are notlegally enforceable. India has neither a tall building code norguidelines
Ensuring earthquake protection: There are anumber of advanced technologies available in the world forprotecting buildings from earthquakes shock transmissiondevices, dampers, etc
Zero accountability: The Bureau of Indian Standardscodes are for general buildings that are up to nine to 10storeys high. While following an international code is fine,using the existing building code meant for 10 storeys is funda-mentally wrong. Both cases offer zero accountability
Responsibilities of a developer: Any developerconstructing a tall building has to submit a detailed plan of theproject. He is also expected to carry out surveys such as windload, earthquake load, environment impact, traffic impact etc
What is required: Awareness and updation of codesevery two to three years. Public should also be made awarethat even if the code prescribes that the building adheres to thelowest level, it can be designed to the next level
Talk to us
Should India have a tallbuildings code?Why or why not?Write to us on facebook.com/htestates
SPECIAL ISSUE
SAFELIVES,SAFEBUILDINGS
SAFETY BE DAMNED
Safety standards set low for Delhi buildings
Vandana Ramnani vandana.ramnani@hindustantimes.com
The highlight of Delhis
Master Plan 2021 is verti-cal growth to accommo-
date the Capitals growing popu-
lation. Despite that, a formalcode for tall buildings does not
exist in the country, and mostbuildings are designed at col-
lapse prevention level which
is a minimum performance
standard.
The National DisasterMa na gem ent Autho ri ty
(NDMA) has, however, come up
with a proposal to set up a Delhitall building council (DTBC) on
the lines of the Mumbais Tall
Building Committee.The proposal was sent to
the Delhi government for itsapproval in 2011. The idea
behind the document will be
to ensure that Delhi is prepared
to meet the challenges related
to tall structures and use it asa tool for better management
of tall buildings much before
such projects come up on theground, says an NDMA source.
The role of the tall build-ing council, as proposed in the
document, will be to guide the
city as it transits from low-rise/medium height structures to
safer tall buildings. As more
tall buildings come up in thecity, a higher level of techni-
cal knowledge and stringentrequirements that may not
be laid down in the municipal
bylaws will be required, the
proposal says.
The draft proposes thatevery agency that wishes to
construct a tall building on the
land that falls under the Delhigovernment, will be required
to present a technical dossier tothe proposed tall building coun-
cil of the government of Delhi.
Potential members of theDTBC could include senior
structural engineers with wind
and earthquake design expe-rience, senior architects with
architectural design and facadedesign experience, senior fire
engineers, senior geophysicists,
green building engineers.
Delhi, Noida and Gurgaon, all part of the high-risk seismic zone 4,are getting ready to go as high as 80 floors. What is alarming is thatthe city does not have a tall buildings code for safety of structures
NDMA has proposed the setting up of atall building council for the Capital
TALL BUILDINGS CODES AROUND THE WORLDChina: The Chinese code iscalled JGJ 3-2010 TechnicalSpecification for ConcreteStructures of Tall Building. Thisis considered the best code inthe world by expertsUS: Tall Buildings Initiative:Guidelines for performance-based seismic design of tallbuildings; Los Angeles TallBuildings Structural DesignCouncil: An alternative proce-dure for seismic analysis and
design of tall buildings located inthe Los Angeles region;Recommendations for the seis-mic design of high-rise buildingsby the Council of Tall Buildingsand Urban Habitat (CTBUH)Japan: The document usuallyreferred to as the JapaneseCode is the Building StandardLaw, including its enforcementorder, which contains require-ments enabling implementationof the Building Standard Law
THINKSTOCK
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12htestatesHINDUSTAN TIMES, NEW DELHI,SATURDAY, JANUARY 25, 2014
on the lines of the Mumbai tallbuildings committee, Raman
adds.Interestingly, local bylaws
do not define tall buildings.Anything above 15 m in height
is generally classified as a high-rise. There is confusion overthe definition of a high-rise
structure and a tall building.Both, a 10-storey building and a
structure above 50 -storey, comeunder the same category. This
is a big loophole, say experts,adding that the Real Estate
(Regulation and Development)Bill, 2013 also does not mention
this issue at all.Most codes in India are 10 to
20 years old. For example, theBureau of Indian Standards
code (BIS) IS 1893 (part 1):2002lays down the criteria forearthquake resistant design
of structures. This is as oldas 2002. Even countries like
Pakistan, Bangladesh andPhilippines have their codes
updated every three years. Whyhave we not updated our codes
for over a decade? The fact thatour codes are not updated is a
big drawback,saysSandeepDonald Shah, managing director,Taylor Design and Engineering
Consultants Pvt Ltd & TaylorDevices India Pvt Ltd, a com-
pany that manufactures earth-quake-absorbing devices such
as dampers.According to Sanjay Prakash,
principal consultant at SHiFt:Studio for Habitat Futures,insurance companies are unpro-
fessionally managed in India.What is needed is an ombuds-
man under the National DisasterManagement Authority, which
might be able to assure that abuilding has been designed and
constructed as per the propercodes.
The issue of accountabilityneeds to be addressed in a bigway. Strangely enough, no engi-
neer in India can be held respon-sible for damage to structures
in any court of law as there isno engineering council such
as the council of architectureunder which architects across
the country are registered. Thecouncil keeps a tab on the stand-ards of practice to be complied
with by the practising architects.A draft of the engineers bill that
proposes setting up a council forengineers has been pending with
the MHRD since 2007, says anNDMA source.
Continued from page 1
SAFETY BE DAMNED
What is a tall building?There is no absolute definition ofwhat constitutes a tall building. Itis a building that exhibits someelement of tallness in one or moreof the following categories:Height relative to contextIt is not just about height, but aboutthe context in which it exists. Thus,
whereas a 14-storey building maynot be considered a tall building in ahigh-rise city such as Chicago orHong Kong, in a provincial European
city or a suburb this may be distinct-ly taller than the urban norm
ProportionAgain, a tall building is not justabout height but also about pro-portion. There are numerousbuildings which are not particular-ly high, but are slender enough togive the appearance of a tall build-ing against low backgrounds.
Tall technologiesIf a building contains technologieswhich may be attributed as being aproduct of tall (eg, specific vertical
transport technologies, structuralwind bracing as a product of height,etc), then this building can beclassed as a tall building. Althoughthe number of floors is a poor indica-tor of defining a tall building due tothe changing floor to floor heightbetween differing buildings andfunctions (eg office versus residen-tial usage), a building of perhaps 14or more storeys or over 50 meters(165 feet) in height could perhaps
be used as a threshold for consider-ing it a tall building.
Source: Council on Tall Buildings and Urban Habitat(CTBUH)
TALL FACTS
Vandana Ramnani vandana.ramnani@hindustantimes.com
Its a safety standard thats bare-
ly there, say housing experts.Most buildings in India are
designed at a collapse preventionlevel which is a minimum per-
formance standard. In countriesaround the world safety of lifeis prioritised.
Developers adhering to suchlow standards can take the easy
way out and not be held respon-sible in case there is extensive
damage to their buildings aftera calamity like an earthquakes.It also costs money to maintain
stringent safety standards. Thecode should clearly state that one
is free to design buildings of ahigher grade, experts add.
Th e N ation al DisasterManagement Guidelines for
ensuring disaster resilient con-struction of buildings and infra-structure financed through banks
and other lending institutionswere brought out in 2010. These
clearly spell out the expected per-formance of buildings (8.2.1) and
assess the safety of buildings infour categories (see box below).
The guidelines mention that thebuilding should be designed so asto meet the minimum perform-
ance level, but it does not stateanywhere that people are free
to design for higher standards.These are some of its administra-
tive flaws, says a seismic expert.Today, low safety standards
are set despite the modern tech-nologies being available to designsafe buildings and maintaining
immediate occupancy (a solidstructure which has all chances
of surviving a quake). In theunfortunate event of a building
collapsing the structural design-er can claim that he cannot be
held accountable as he has fol-lowed the code which requiresminimum safety standards. Hell
simply say that the structure isweak because it conforms to
the minimum requirement, theexpert adds.
The cost of building a struc-ture at an immediate occupancy
level comes to`300 per sq ft morethan collapse prevention level.
Indias structures are built forminimum damage control
Safety compromised in buildingsTHE FOUR PERFORMANCE LEVELS OF BUILDINGS
Fully opera-tional level:This means thebuilding in theaftermath of aquake has everychance ofremaining oper-
ational with electricity, air condi-tioning, lifts etc all working. Nodamage is likely in the buildingand its functions are not likely tobe disrupted
Immediateoccupancy per-formance levelmeans a buildingcan remainintact after anearthquake butits services are
likely to get damaged. The function-ing of such buildings are likely toresume immediately after a quake
Life safety per-formance levelmeans the struc-ture can getdamaged in anearthquake butsuch damagesare likely to be
minor and can be repared. Therecould be significant damage to thebuilding but it would not collapsedand could be retrofitted
Collapse pre-vention per-formance levelmeans the build-ing and its utili-ties can sustainmajor damage inan earthquake.
The structure can also be in thedanger of collapsing completely.The building can also becomeuninhabitable after a quake
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