Challenges faced by Underwriters or insurance companies in insuring sandwich panel structures

1. Phani Kumar K
Sr Manager – Risk Management & Survey
Challenges in Underwriting
Insulated Sandwich Panel structures
Glenfell Tower in North London
The catastrophic fire accident at Grenfell
Tower in North London on 14th
June 2017
grabbed attention of Insurers and the Safety
Professionals across globe. The devastating
fire caused 79 causalities and irreversible
damage to the residential apartment.
Although, malfunctioning fridge on 4th
floor
was presumed to be the cause of loss, what is
important is to understand the cause of
causalities & extensive damage to the
structure. Originally built in 1970, Grenfell
tower has undergone extensive major
revamping in the year 2014. Exterior wall
cladding with Polyisocynurate (PIR) foam
sandwich panel was part of the
refurbishment activity undertaken for
improvising appearance and for improvising
energy efficiency. However, it is attributed
that PIR panels used in exterior cladding
played major role propagation of fire across
the 24-storied residential apartment. Toxic
Hydrogen Cyanide & Carbon Monoxide gases
released by the igniting PIR panels is major
reason for the causalities.
PIR panels are verified to have low thermal
conductivity ratio with improved fire safety
compared to Polyurethane (PUF) or
Expanded Polystyrene (EPS) sandwich panels
which are extensively used in India. All these
foams are sandwiched between two
aluminium sheets of required dimensions and
having about 1mm thick, to provide the
strength and to avert direct exposure of
foam. However, all these PIR / PUF / EPS
foams would burn if exposed to naked fire
and release toxic gas as other organic
matters does.

2. Phani Kumar K
Sr Manager – Risk Management & Survey
Fire at Hitachi Air Conditioner Manufacturing
plant at Kadi – Gujarat in the month July’2012
is another major incident involving sandwich
panel structure, where entire structure
collapsed & caused loss exceeding Rs. 100
crores. 22 fire tenders rushed to site and
fought fire for 10 hrs to douse it completely.
But, the structure made of PUF panels could
not be saved and the roof had collapsed.
Employees walking over Collapsed roof of Hitachi
Another recent Rs. 16 Crs loss due to fire in
Teekay Marine P. ltd’s Prawn processing unit
at Bhubaneshwar was also found used EPS
sandwich panels for their cold storages. The
roof made of EPS panels of the Cold store 1
totally damaged in fire and the temperature
of the stocks increased resulting into heavy
loss to stocks on account of Deteriorated
Prawn stocks.
The nature of losses in all these cases is
common. Sandwich panels contributed to fire
load and resulted into structural damages
and in some cases total structural collapse.
Damaged Cold store 1 roof
However, sandwich panels are now widely
used in India especially in Cold storages, Sea
food / meat processing units, fruit ripening
units, formulations units, Beverage
manufacturing units etc. Sandwich panels are
also used in temperature controlled areas like
CNC equipment areas, office premises,
shopping malls etc. primarily to save energy
bills and installation time.
Although fire-retardant sandwich panels are
available in market, it is observed that once
exposed to naked flames all foam panels burn
and emit smoke like any other organic matter
beyond rated temperature.

3. Phani Kumar K
Sr Manager – Risk Management & Survey
Firefighters avoid entering the sandwich
panel structures fearing their own safety.
They concentrate on preventing fire from
spreading to other structures, leaving the
block to burn itself out as it is extremely
difficult to extinguish the fire in foam panel.
Further, even if fixed properly; upon exposed
to the flame or heat, steel frames on which
the panels are fixed will be distorted, bolts
used for fixing would fail and expose the
foams to naked flames resulting in severe
blaze with toxic gas release.
During our visits to various sites, we observed
that the panels are punctured / drilled / cut
to pass the electrical cabling, piping through
it and the foam is let exposed carelessly.
EPS Panels drilled / holed for laying cables
If drilled / punctures / cut, the exposed foams
need to be sealed with fire-retardant sealants
/ tapes which we never observed.
Further, extra care need to be taken for hot
or cold works like cutting, welding, drilling,
pipe fixing etc. However, majority SME units
have many lapses and don’t follow permit
systems.
Underwriters need to be more cautious
while insuring property consisting of
Sandwich panel structures. Underwriters
may ask for the detailed risk inspection
report along with the fire-retardant
rating of the panels, observations on
punctures /cut in panels and sealing
techniques of exposed foams, work
permit practices etc. Probable Maximum
Loss estimates shall always be considered
100% of assets within these structures.
Facilities predominantly having PUF panel
structure may be rated as Kutcha
structures.