Cladding maintains the privacy and security of exteriors, provides access to ventilation and hygienic environment, and prevent the spread of fire. Basically, its properties like termite resistance, waterproofing nature, environmental friendliness, and their wide range of colours & designs make cladding a trend, notes Rachhpal Kanwar, General Manager – Exterior Cladding and Cubicles, Stylam Industries.

1. Cladding Choices
Over the years cladding industry has been going through a sea change. Along with a flood of
innovative materials and designs introduced in the market, we see the advancement in
technologies in application as well. As per a research report ‘Grand View Research, Inc.’, the
global cladding market is expected to reach USD 111.1 billion by 2025 and is projected to grow
at a CAGR of 2.6 per cent from 2017 to 2025. The increasing construction spending and the
development of more efficient building technologies using automated production and installation
processes is expected to foster industry growth.Stringent green building regulations and codes
such as the LEED certification, and growing demand for energy efficiency in project exteriors,
especially for key construction industry participants, including architects and designers, are
encouraging investments in lightweight and energy efficient exterior panels in commercial as well
as residential buildings. Choice of cladding has a significant effect on the environmental
performance of a building.
We spoke to several experts in the construction sector, including architects, façade consultants,
manufacturers of cladding materials and builders on the advancement in cladding sector, the
newest in cladding technologies & materials, fire tests and fire performance of external cladding
systems. Here is what experts have to say about the latest in the industry.

2. Godrej One Mumbai Picture courtesy Aluplex
PURPOSE OF CLADDING
Cladding serves many purposes, including creating a controlled internal environment, protecting
the building from external conditions, preventing the transmission of sound, for providing thermal
insulation and improving appearance of buildings, among other things, says Amit Shah,
Managing Director, Classic Marble Company.
Cladding maintains privacy and security of exteriors, provides access to ventilation and hygienic
environment and prevent the spread of fire. Basically, its properties like termite resistance,
waterproofing nature, environmental friendliness, and their wide range of colours & designs make
cladding a trend, notes Rachhpal Kanwar, General Manager – Exterior Cladding and
Cubicles, Stylam Industries.
The main functions of any cladding are to provide enclosed area which will provide protection
from all-weather condition like rains, wind, cyclone; also the safety of inhabitants is major
concern while designing a cladding system. According to Upendra Walinjkar, Director,
Aluvision Façade Solutions Pvt Ltd., all these can only be achieved with very good structural
and system design.
Alhad Patil, Technical Director, Diamond Metal Screens, observes that exterior cladding,
especially perforated metal façades, plays an important role on the structural aspects of the
building. Being generally light weight in nature – due to perforations, they add minimal weight/sq
m to the building, while adding a host of advantages such as ventilation, sun screening and more
importantly dissipating heat absorbed structurally through the aluminium second skin.
According to Akash Saini, Director, Notion Flooring, cladding not only provides protection but
also enhances the architectural concept and appearance of the building. Its impermeable and
porous material helps to absorb water during rainfall and completely keep out the rain infiltration
and keep buildings secure and safe.

3. Purpose of cladding:
 Create a controlled centralised environment
 Protect the architecture from alien conditions
 Prevent the transmission of sound
 Provide thermal insulation
 Create an external façade
 Prevent the spread of fire
 Generate an ‘airtight’ architecture envelope for building
 Provide openings for access, lights and ventilation
STRUCTURAL ROLES OF CLADDING
Cladding, even though essentially the nonstructural secondary surface attached to the primary
structural surface of the building, has a fitting effect structurally on the building, points out Prof.
Charanjit S Shah, Founding Principal, Creative Group. Though it is merged with the primary
face of the structure, it does not contribute to the stability on the whole. Regardless, it does play
a structural role transferring wind loads, impact loads and its own weight back to the structure
which implies that ample amount of strength is required both within the cladding system and its
joineries for the primary face to ensure that it does not crumble under wind load pressures.
Walinjkar too agrees with this statement.
According to Rohan Keswani, Director,Aluplex India Pvt Ltd, curtainwalls and cladding
materials are designed and engineered to withstand wind loads based on the topography and
geometry of the building, the deadloads of the curtainwall, the live loads imposed, seismic loads
and thermal loads, whilst also accounting for loads imposed on the cladding due to building
movements such as column shortening and creep movement. The cladding is designed to limit
the deflections of the cladding framework and infill panels within serviceability limits, as desired.
More importantly, design and engineering checks are carried out to ensure that the stresses
within the façade elements are limited to the yield stress to ensure that there is no permanent
deformation of the materials. Further, the framing members of the cladding are designed,
engineered and checked to ensure that there is no buckling caused by the compression loads
imposed in the axial direction (Euler Buckling), as well as, the compression loads imposed due to
bending (by lateral torsional bending).
In explicit, wind causes positive and negative pressure on the surface of buildings and cladding
should have ample strength and stiffness to resist this load, each in terms of the types of
cladding chosen and its connections back to the structure, explains Rajendra Shah, General
Manager – New Age Products, Century Ply. Cladding can help to reduce mechanical and
electrical energy needs, and so enhance electricity efficiency and lower the running costs, he
adds.

4. Curved Metal cladding
KEY FACTORS TO CONSIDER WHILE DESIGNING AND
SELECTING MATERIALS FOR CLADDING
Cladding of any building requires engineering characteristics, should be aesthetically appealing,
and should comply with visuals, says Rajan Govind, Director & Façade Specialist, BES
Consultants Pvt Ltd.
Selection of material depends on factors like the architectural intent of the designer, types &
properties of the product, the loading factors at desired location and elevation angles,
adds Shabbir Kanchwala, Senior Vice President, K Raheja Corp.
In today’s context, choosing the right cladding system is essential to bringing in the
environmental impact of the building down in a future context as façade construction accounts for
almost 35 per cent of the building costs, adds Ar. Gurpreet Shah, Principal Architect, Creative
Group. A few other factors that might be essential to the selection of materials for the cladding
system should be – usage type of the building, internal and external conditions, durability, local
context, planning requirements, accessibility and buildability, appearance, availability, budget,
maintenance requirements as well as the structural requirements.
According to Devesh Kumar, Sr. Manager – GICS & Technical Support, Aludecor
Lamination Pvt. Ltd., in addition to the above points, the key factors for selecting the material
for cladding are its ability to withstand wind load and fire ratings of the product.
Factors like building height, seismic conditions and required product size too decide the type of
cladding, adds Julie Etavard, Business Development Manager (in charge of India market),
Terreal.
Consideration of wind factor is important for selecting the thickness of the cladding,
says Patil. Open areas decides the ventilation factor. The structural framing design of the panel
is imperative for withstanding static and other dynamic structural loads. The material grade and
coating decides its life span, preventing corrosion. According to Patil, the best choices are
aluminium (marine grade – 5xxx series) considering saline environment, and Stainless steel 304
grade, though they are expensive but long lasting.
According to Keswani, the key factors to be considered while designing and selecting materials
for cladding are structural performance, corrosion resistance, water tightness, air permeability,
thermal resistance (by conduction/convection/ radiation), aesthetic intent and artistic finish, and
reduction in carbon footprint.
Points to consider while designing and materialselection:

5.  External and internal conditions
 Use of the building
 Resilience, strength and durability
 Fire resistance
 Planning and requirements
 Building regulation requirements
 Accessibility and buildability
 Aesthetics
 Availability & budget
 Maintenance requirements
 Structural requirements
 Control of air leakage
 Integrity and continuity of Insulation
 Prevention of water penetration or provision of drainage
 Control of thermal movement • Ease of installation
 External attachments and fixings
(Inputs by Rajendra Shah, General Manager – New Age Products, Century Ply)
Metal cladding with light
THE BEST SUITED PRODUCTSCONSIDERING INDIAN
CLIMATIC CONDITIONS
The Indian weather ranges from tropical in the south to temperate in the centre to Alpine climates
in the North. So depending on the region, the choice in cladding materials could vary. Indian
climatic conditions require any façade materials to be of external grade that could withstand

6. harsh conditions like hot and humid weather, and also highly durable on wet and dry climates,
observes Rajan Govind. Market is flooded with traditional materials (brick, stones, wood) to the
most innovative ones like Corian, Hi-Macs (an acrylic solid surface), Cor-Ten steel, etc., most
common products used being wood, metal, brick, vinyl, and laminates. According
to Keswani, the most suited cladding materials are those with low emissivity which reduces heat
losses by radiation. He adds that in temperate climates, the primary heat transfer method is
conduction and thus, the most suited cladding materials are those with low thermal conductivity,
thus we use materials such as thermally broken aluminium profiles as well as double glazed
units.
Considering Indian climatic conditions, explains Walinjkar, one need to choose cladding having
following properties:
 Resistance to corrosion: Materials shall be having high corrosion resistance like aluminium,
steel and they should be properly treated with hot dip galvanizing and epoxy or PU paint.
 Cleaning and maintenance: We must know the cleaning cycle of the external building envelope
while selecting cladding. (If cleaning cycles are not regular then we need to select material which
will attract less dust and with minimum horizontal surfaces as architectural features, flush seal
systems must be avoided, non-bleeding sealants need to be used for weather proofing of
system, etc.)
Diamond Metal Screen
Walinjkar suggests glass, aluminium solid sheet, aluminium composite panels (FR grade A2),
natural stones, terracotta, pressure laminates (HPL), copper cladding, zinc cladding, fibre cement
board cladding, Corian cladding, GFRC etc. as best suited cladding materials.
There are varieties of cladding materials/systems used these days. It’s quite difficult to
distinguish them from one another and numerous methods for installation too, says Rajendra
Shah. The most suitable products are those which do not contain any hazardous substances like
ash or asbestos. According to him, the best suited are fibre cement board (FCB) & fibre cement
panels. However, the all-weather cladding material popularly opted in the country are engineered
marble and porcelain tiles, points out Amit Shah.

7. Saini chooses wooden cladding and waterproof aluminium cladding as the best suited products.
Unlike the traditional cladding, they both can be easily fixed in the least amount of time, is
exceptionally durable, lightweight and maintenance free, weather, moisture, and UV resistant as
well as eco-friendly cladding. These materials do not rot, warp, peel or fade and is even
impervious to insects, adds Saini. It is also one of the pleasant materials that neither gets too hot
or nor too cold, maintaining the stability regardless of the external conditions. Further, stone and
ceramic materials are also used in the cladding that provides earthy effect and also eco-friendly,
helping the overall performance of the building.
Architects from Creative Group suggest terracotta panels as the most suitable cladding material
since they are durable, resistant, requires minimal maintenance, thermally insulated and
aesthetically providing another dimension to the building. “Our highly intensive tropical climate
calls for more measures towards ‘green cladding’ that will be able to add more years to the life of
the building,” adds Charanjit Shah.
Julie Etavard too emphasises that terracotta cladding is compatible and excellent for Indian
climate conditions. Terracotta panels have low-thermal diffusivity; it contributes to a stable and
comfortable indoor temperature during the day and night. Its ventilated system allows air to
circulate throughout the panels (joints are not sealed) and cool down the whole facade. Also,
they are fired over 1000 degrees celsius resulting to have fixed colours which will not fade over
time and which are UV resistant. Pollution and acid rain are not damaging the products and they
are maintenance free. Clay is a natural and inert material; meaning through its natural property, it
keeps the heat received during the day and release it when it’s cooler during the night, helping to
control the temperature inside, she adds.
To ensure the cladding accustoms itself to the geographical climate, products like Mangalore
roofing tiles or exterior stone finish that can be sourced from the local region and is abundantly
available, are the best bet, suggests Kanchwala.
HPL (High Pressure Laminate) is the best for exterior cladding, says Kanwar, as it can be
exposed to combined action of sunlight and atmospheric agents including rain, hail or wind
deposits. These are not affected by thermal shocks and have the ability to withstand extreme
climate changes. Further, it reduces the amount of water that is absorbed and provides
protection against chemical or air pollution.
Wooden cladding
ROLE OF CLADDING IN CONTROLLING THE INTERNAL
ENVIRONMENT
The primary functions of cladding is to split the indoor environment of a building from the outside
in such a way that the outdoor environment will not affect the indoors. It is also best for regulating

8. the light penetration and controlling the radiation and conduction of heat from the sun, and
prevents interiors from getting faded and dull. Additionally, sunshades and louvred panels allow
for reflected light to enter the building that enhances the comfort, rather than direct sunlight.
Stylam Industries
Gurpreet Shah emphasises that the cladding is like a thermal layer to minimise heat gain/winter
frost gain. If installed correctly with proper vapour cavities and ideally using climate favouring
cladding materials with adequate insulation, the thermal mass can be rightly reduced, which in
turn would make the internal environment of a structure very pleasant with little or no requirement
for mechanical measures to regulate the temperatures inside. Adding to this, Kanchwala points
out that designs like filler slabs, double roof, cavity walls, composite walls, and shadings also
help insulate buildings.
Contrary to the above comment of Gurpreet Shah, Rajan Govind observes that for Indian
climatic conditions, insulations do not necessarily add significant benefits (except in very hot
regions). Insulated cladding will benefit in reducing heat loads only for very hot climates,
notes Govind. Furthermore, such cladding is majorly used on walls in front of shear wall or
beam/column locations. He also points out that any cladding system should be equipped with
ventilated rain screen principle, so that the cladding system will have an extended life and lesser
risk of corrosion and damage.
Guwahati data centre

9. A façade which is ventilated and insulated can save up to 70 percent energy costs for heating or
cooling the building. Cladding of a building ensures that the internal temperatures are maintained
at ideal levels, reducing both the cost burden of HVAC and impact on the ecology, states Amit
Shah. Another point mentioned by him is the protection from water permeation. Many parts of
the country experience heavy rains and cladding serves as a coat which reduces the infiltration
of water into the primary structure.
ACOUSTIC PERFORMANCE
The acoustic performance of the cladding depends upon the substrate behind the cladding which
may vary as per the thickness of the wall and constructions, says Amit Shah. Devesh
Kumar adds that insulated façade provides better sound absorption.
According to Rajendra Shah, the isolation of noise is excellently achieved with partitions which
are airtight, large and resilient. The use of the resilient pad prevents transfer of sound originating
inside the structure to outdoor, vertically through the cladding members, he adds.
Deviating from the above views on the acoustical properties, Gurpreet Shah points out that
cladding necessarily does not provide adequate sound insulation with the exception of brick (a
high mass, high thickness system).
The level of acoustic attenuation of the cladding material is decided based on the type of external
and internal environment, with respect to the frequencies and amplitude of the ambient noise and
sounds. Laminated double glazed units having a varying glass thickness, with acoustic PVB is
the best choice for acoustics, states Keswani.
CLADDING FOR BETTER THERMAL INSULATION AND
EFFECTIVE VENTILATION
Facades are designed with passive and active ventilation, such as double skinned facades that
allow the warm air to rise, and exhausted from the void between the two skins,

10. explains Keswani. Additionally, for high-rise buildings where windows cannot be opened due to
high wind pressures, passive ventilators are the solution, which can be opened and closed. This
allows for air circulation through the façade without the need to open the window.
Rear ventilated facade concept is quite popular and helps saving energy costs, while increasing
the lifespan of building sustainability, spots Kanwar. He warns that poor design, detailing or
installation may compromise cladding’s performance and can result in safety problems like
cladding collapse or cladding panels pulling away from the structure. One should pay particular
attention towards control of air leakage, thermal movement, condensation, integrity and
continuity of insulation, prevention of water penetration, maintenance, resilience, etc., while
selecting or designing cladding to gain effective results in both thermal insulation and effective
ventilation.
The cladding assembly can control the radiation and conduction of heat. Cladding is made from a
low conductive material to stop localised condensation on interior surfaces. It eliminates thermal
bridges and controls/stabilises the desired degree of the conduction of heat into and out of the
building.
Prof. Charanjit Shah too states that the integration of thermal insulation with the cladding
system (the most common insulation materials being mineral wood and polystyrene), forms a
closed insulation envelope which helps to eliminate thermal bridges. The ventilated air gap
between the primary face and the cladding face is responsible for draining the heat and moisture
from outside the building and prevent it from reaching the interiors which regulates thermal
insulation to the greatest extent. Composite claddings having insulation with higher R-values (the
measure of a material’s resistance to heat flow) can eliminate the need for bulk insulation
between the frames in many climates. With effectively designed and efficiently mounted vapour
cavities, condensation risk can be reduced or eliminated. Tensile fabric can alternatively be
considered as a second cladding layer which provides a facade as well as shading to a structure.
With a selection of the better cladding system, says Walinjkar, we can achieve the desired value
of thermal insulation. Wide range of products is available with low thermal conductivity (U-
value). Widely used curtainwall systems can control the heat transfer from hot external ambient
temperature 300C – 450C to an internal ambient temperature of 200C -240C by introducing the
barrier of EPDM gaskets for better thermal insulation. Polyamide strips are used to cut the heat
flow from either side and provides the best thermal values.
HOW TO ACHIEVE DESIRED U-VALUE:
 With the use of Rock wool and mineral glass wool, we can achieve very good thermal insulation
on a spandrel area of facade by increasing overall system U-value.
 Curtainwall claddings support effective ventilation by use of openable vent. With advanced
technology we can use active or passive ventilation in the facade, there are development in
accessories for openable vent to maintain micro ventilation. Micro ventilation keeps the room well
ventilated.
 The double skin facade provides great flexibility for the best combination of U-value and effective
ventilation to remove hot air by natural or force ventilation. The skins may be single or double
kept 20cm – 100cm.
In the application, considering the cross-section of a Trombe wall, says Rajendra Shah, both the
insulation values and transparency of the cladding material are of critical considerations,
particularly in cooler climates where night time heat loss can offset the daytime heat gain.
Trombe walls rely on the combined action of thermal lag of the mass and insulation from the air
gap. Unwanted convection is controlled with open able vents at the top and bottom of the wall.
Additional insulation can also be gained in cooler climates through the use of double glazing
(higher SHGC, lower R-value) or multi-celled polycarbonate (lower SHGC, higher R-value).
In India, one of the biggest energy consumption for buildings is its HVAC. Cladding structures
ensure a significant reduction in the HVAC costs while reducing the carbon footprint. A marble
clad façade can be made opaque with a set degree of opaqueness which is suited to a given

11. environment. According to Amit Shah, this ensures that the building receives sufficient light
while cutting off external noise and air pollution.
Platina BKC Mumbai
FIRE SAFETY STRATEGIES OF CLADDING
Fire safety is the set of practices intended to reduce the destruction caused by fire. Local
regulations for safety norms should be followed to achieve desired level of fire safety by use of
appropriate materials.
Cladding materials play a key role in fire safety, hence it is important to choose the right
materials. In lieu of the recent fires that have devastated many a buildings around the world
(read. Grenfell Tower Fire) a shocking revelation has emerged, use of substandard cladding
panels or an improper installation of the cladding system can undermine the safety of an entire
building.
Fire safety of cladding need to be addressed at the selection stage itself and any cladding
material should comply with fire retardant characteristics and relevant international
standards/local standards if exists.
Sometimes, what’s meant to protect the building from the external environmental discomfort
might turn out to be the cause that facilitates fire, warns Ar. Gurpreet Shah. It, in turn dissolving
other firefighting measures such as fire compartmentation and phased evacuation strategies. We
can avoid the loathe of such hazards by ensuring that the cladding systems that have undergone
proper fire safety tests and have the highest level of insulation magnitude. Another important
point on the checklist is ensuring that the cladding systems are installed properly with proper
joineries and fixing details.

12. GRC cladding
Fire safety strategies of curtainwalling include the use of firestops and smoke seals to limit the
spread of the fire and smoke from floor to floor, points out Keswani. Conventionally, the use of
GI sheets with Rockwool Insulation and fire sealants have provided a two hour resistance.
However, today, there are tested assemblies available from companies (such as Siderise and
Hilti) that provide a warranty and certification for the same. Additionally, it is also important that
the cladding material should not propagate and are non-combustible so as to limit the spread of
fire along the external façade. There is a risk in fire conditions that composite panels are
attacked at the joints or the panels suddenly delaminate and the metal facing fall away, thus
exposing the combustible core which then intensifies and spreads the fire, observes Rajendra
Shah. The sudden increase in fire severity can accelerate the failure of the adjacent panels, so
that if a fire does take hold, it can race up or through an entire facade of a building, causing a
major hazard to occupants and a major property loss.

13. A project by Diamond Metal Screens
There is a lot of ambiguity in choosing the right materials due to consideration of inappropriate or
inadequate information during procurement. Yes, overall in the industry, there is a significant shift
from conventional materials to fire retardant (FR) materials, agrees Kanwar. HPL, even in
standard grade, does not burn very well, or rather, do not ignite easily when exposed to flames
and contribute relatively low in the event of a full scale fire. Flame retardant HPL is manufactured
with special halogen free additives that make it flame resistant, complying with Standard EDF -
(EN 438-6 Fire Retardant). “More technically, fire resistance is the ability to retain the load
bearing capacity (R), integrity (E) and insulation (I) properties for a defined period of time and it is
useful to use REI properties while constructing buildings,” explains Kanwar.
The small-scale reaction test can also be done for cladding materials which provide better
knowledge on reaction of materials. It’s also very important to check the products that are used in
multi-storied buildings (18m or above) and they must be of limited combustibility.
Cladding material which is rated for fire safety and fire performance, and those which normally
incorporate an insulated core (such as sandwich panels), are apt for containing fire spread in a
building, stresses Akash Saini
Fire strategies can play a major role in the case of any fire hazards.
 Surface propagation: The reaction to fire characteristics of the materials used within the
external cladding system will affect the rate of fire spread up the building envelope by way of the
surface of the external cladding system. By using fire retardant materials in cladding, we can
avoid huge fire hazards.
 Cavities: Cavities may be incorporated within an external cladding system, or may be formed by
the delamination or differential movement of the system in a fire. And this cavity may act as an
insulation chamber between internal and external environment.
 Fire breakout: Following the initiation of a fire inside the building, if no intervention occurs, the
fire may develop to flashover and break out from the room of origin through a window opening or
doorway.

14.  Fire re-entry: Cladding system in window and door stops fire re-entry.
 Fire service intervention
FIRE TESTS AND FIRE PERFORMANCEOF EXTERNAL
CLADDING SYSTEMS
The overall fire performance of the system is reliant on the interaction of all the elements used
within the cladding system, i.e., rendered insulation, ventilated cavity cladding and built-up
systems.
There were various tests conducted to check the performance of cladding materials. Talking
about the building codes for fire and life safety, Devesh Kumar points out that in India we have
National Building Code 2016 in Chapter 4 ‘Fire and Life Safety,’ where it is mentioned to use
façade with a fire rating of Class 1 in accordance to IS12777 and the material along with
assembly to be tested for 2 hours. Kanchwala too agrees that, as per Indian Standard code, the
materials shall comply with the requirement of IS 1642 & IS 12777 having flame spread index
matching to the requirements.
Devesh Kumar further adds that for fire performance test for resistance to fire, first we should
have a 2 hour test from ASTM E119 and then the assembly should also pass either NFPA285 or
BS8414. For resistance to fire EN13501-1 can test flame, smoke, molten droplets and heat
released. The material to be used up to 15m building height should be Class B S1 D0 and above
15 m should be Class A2 S1 D0 in accordance to EN135011.
BS8414 is one particular test method which was specially developed to demonstrate under a
simulated fire in a compartment breaking out of any opening in the external wall, the cladding
system will not permit excessive fire spread up the building. Accordingly, each cladding material
is rated for fire resistance, elaborates Keswani. However, there are certain suppliers, who
provide samples for the test that differ from the material that is actually supplied to the project.
Hence, one should ensure that random samples are sent to the test laboratory from each batch
of material delivered to the project site.
If the materials in an external cladding cannot meet limited combustibility requirements, then it is
very important to demonstrate compliance with AD B by testing the cladding as a whole and
satisfying the performance criteria in BR 135 (As per the guidelines mentioned in the
requirements of Building Regulations in the UK, Part B Fire Safety). It is also very important to
check the installation and testing of a complete cladding system, which allows materials
themselves be combustible with meeting the requirement of BR 135 which helps in maintaining
the appropriate safety standards (BR 135 Fire performance of external thermal insulation for
walls of multi-storey buildings. 3rd edition BRE (2013).

15. Raipur Airport
There are several tests being used globallyfor cladding
materials depending upon the regions and building
regulations:
 ISO 9705 room test: Products are tested to simulate their end use application, so products which
have different end use applications can achieve different classifications.
 The single burning item test (EN 13823) measures the spread of flame, heat release, smoke
production and the extent of flaming, burning droplets.
 The small flame test EN ISO 11925-2 evaluates the ignitability of a product exposed to a small
flame ignition source and measures flame distances, the burning time and any flaming droplets
or particles generated.
 Large scale test
 BS 8414 -1: 2002 is the test method for non-load bearing external cladding systems applied to
the face of a building. The test determines the comparative burning characteristics of exterior
wall assemblies by evaluating the characteristics:
– Fire spread over the external surface
-Fire spreads internally within the system being tested
– Mechanical response, i.e. the degree of distortion.
Source: Rajendra Shah, General Manager – New Age Products, Century Ply
Two availabletests for HPL cladding materials:
 BS 476: Part 7: 1997 – Class 1 results in this test means the HPL exterior cladding used is of
good quality. According to Class 1 test result, the spreading time and extent of fire over the
tested panels are very slow. While Class 4 means quick flame spreading. So HPL with class 1
results are safe to use at our homes and buildings.
 REI Property – Fire resistance is the ability to retain the load bearing capacity (R), integrity (E)
and insulation (I) properties for a defined period of time. In the construction of buildings, this is
assessed for finished elements with structural functions (e.g. doors or walls) in which the HPL
laminates are just one component. REI 30 or REI 60, here numbers show the time in minutes for
which the HPL panels will retain their properties. So higher the numbers in REI properties, good
and safer will be the HPL panels. Stylam Industrie

16. APT CLADDING PREVENTSSPREAD OF FIRE
The new concepts, materials and ways that have emerged in the millennial world tends to put
aesthetics above safety quite a many times but fails to realise that aesthetic will follow the lead of
safety in the long run. A properly tested, installed and maintained cladding can not only provide
shelter from external factors, but can also be the reason that the fire never spread to the entire
structure and was uprooted at its cause itself. Therefore, the cladding material should not
facilitate catching fire at the surface and in worst case scenarios, when it does, it should phase
away from the building to prevent fire from spreading to the vicinity thus, successfully preventing
a disaster.
To decrease the risk of spread of fire through building facades, two options of passive fire
protection could be considered, points out Kanwar – by using flame retardant treatments to
improve the reaction to fire performance of the cladding material in the entire design and
geometry of the façade; and by using construction elements capable to avoid the contact
between the fire plume and the combustible cladding.
The first axis of the so-called passive fire protection consists of slowing down the development of
a fire and its rapid spread by using construction materials with low flammability and
combustibility, explains Rajendra Shah. This measure is related to the reaction to fire of
materials such as wall, floor, ceiling and facade claddings as well as materials that are in the
vicinity of the exposed surface. Passive fire protection relates to the building’s structure as well
as to the building’s finishing and relies on the following principles:
 The use of cladding materials with good reaction-to-fire characteristics, in order to delay the
development of an incipient fire.
 The realisation of compartmentation to confine the fire, for a defined period of time, to the
compartment in which it started. A high fire resistant cladding material can achieve this to an
extent.
 To preserve the load-bearing function of structural elements (columns, beams, walls) during the
fire, appropriate cladding material selection is important. The key points regarding fire safety are
to prevent spreading of smoke and fire in the building. Suitable fire stops and smoke seals play a
crucial role in preventing the spreading of fire. Additionally, fire retardant materials are used for
external cladding. There is provision for necessary openings for safe evacuation & passage of
smoke. The framing which holds the cladding makes it robust and prevents the structure from
collapsing during a fire spread.

17. How can apt cladding prevent spread of fire in building
facades?
 Passive fire protection: It consists of slowing down the development of a fire and its rapid
spread by using construction material with low flammability and combustibility.
 Fire and smoke stop: To stop the spreading of fire between floors, the gap between the building
and the cladding system must be treated with 2hrs fire rating and sealant to stop the smoke.
 Vertical fire separation: Top stop the spread of fire between two rooms vertical fire separation
is a must. The separation shall be done using fire rated material with 2 hours fire rating.
 Cladding material: Selection of right material plays a major role in fire safety, there are many
projects where lives are lost and lots of destruction happens due to use of wrong cladding
materials. Cladding material must have Fr grade A2 class (No significant contribution to fire at
any stage of the fire)

18. The Water Cube Stadium in Beijing ,China
THE WATER CUBE STADIUM IN BEIJING, CHINA
Consider the case of ETFE (ethylene tetrafouroethylene) panels at The Water Cube Stadium in
Beijing, China. In the said case, the cladding material possesses this amazing property of “self-
shrinking” or melting away from the structure, thus letting the smoke out and in turn facilitating
ventilation during a fire hazard. It is necessary in today’s scenario to consider materials with a
low carbon footprint as well as recyclable materials. Always remember the performance in testing
relates directly to real fire performance, reminds Saini. So to know how to prevent the spread of
fire in building facades, do the test under the simulated whole-room fire in a compartment being
emitted from an opening in the external wall, the cladding system will not permit excessive fire
spread up the outside of the building.