2. Xxx
FOREWORD
2
We have extensive experience of undertaking complex
projects where we have worked with occupiers to develop
their requirements and used our substantial project
management expertise to deliver their expectations,
resulting in buildings that positively enhance their business.
Many of our projects are undertaken in occupation and
we are adept at reviewing the strategy to advise on the
phasing of work to minimise disruption to the occupiers
while reducing costs and maintaining business continuity.
Peter Bicknell, Client Services Director (Head of Technical Services)
Peter Bicknell, Client Services Director
(Head of Technical Services)
Paul J Warrington, Engineering Manager
Foreword
5. 1.0INTRODUCTION
5
1-2 Broadgate consists of 305,272ft2
of floor area spread
across six levels occupied by a range of businesses
including ICAP, Royal Mail, KBW, Regus, Precise Media,
Brookfield Multiplex, ETX and GF Securities.
A four year comprehensive refurbishment programme
was carried out at the property restoring key elements
of the mechanical and electrical building infrastructure
with the aim of extending life to 2019. A key aim of
the project was to give confidence to the occupiers
ensuring their needs will be fulfilled in the future so they
can re-gear their lease and extend the duration of their
stay in the property.
The works were completed in three phases between
2012 and 2015, whilst the building was fully occupied.
Prior to the programme, the majority of systems and
equipment in the property had not undergone significant
upgrades from the systems installed during the initial
development of the property in 1986. An exception
being the transformation of the chilled water air
conditioning system in 2005 from a centralised system
to a quadrant chiller system with dedicated chillers and
AHUs housed on each floor. However the majority of
equipment in the building was approaching the end of its
serviceable life at the time of the programme.
In order to initiate the refurbishment project, Broadgate
Estates were invited by the landlord to summarise and
advise on the engineering systems within the property
with respect to suitability, reliability and obsolescence
of the equipment. Additionally any major equipment
or systems which had exceeded or were nearing their
service life were identified for replacement to ensure the
needs of the occupiers can be fulfilled until 2019.
A key aspect of the project initiation process was the
risk assessments carried out by Broadgate Estates on
all 386 engineering systems and assets in the building.
The assessments resulted in risk ratings being given
for the potential failure of all equipment and systems.
This was based on multiple factors such as condition,
compliance and service impact upon failure. Based on
the risk scores, equipment were prioritised within the
four year programme which resulted in the equipment
that was likely to pose the highest potential risk to the
occupiers’ business being addressed within the early
phases of the programme.
In order to transform these findings into specific work
items, Broadgate Estates commissioned several
specialists engineering service providers to propose
technical recommendations for the work required.
These proposals were utilised as guidance to produce
a detailed version of the phased refurbishment plan
spanning the four year period.
1.1 General
6. 1.2 Project summary
The most significant and critical parts of the refurbishment
works were completed during phase 1 over an 18-month
period. The most notable of these works was the
replacement of the two dedicated chillers and cooling
tower which provide cooling to the occupiers’ UPS
facility on an N+1 configuration.
Further replacements were carried out of two chillers
located on the sixth floor whilst the floor was fully
occupied. Broadgate Estates ensured that occupiers’
cooling needs were continually satisfied by installing
and managing similar sized temporary chillers on the
roof for the duration of the works.
A complete refurbishment of the rest of the cooling
system in the building was undertaken during the three
phases. This included replacement or refurbishment of
78 primary and secondary chilled water and condenser
pumps, 22 chillers and 12 cooling towers in the building.
All of these works involved the contribution of multiple
contractors who worked on site simultaneously as
planned and coordinated by Broadgate Estates.
This ensured efficient and timely completion of work
packages with minimal downtime of systems.
Through meticulous planning and careful co-ordination
between the multiple parties, the cooling system
refurbishment works were completed without interruption
to occupiers’ air conditioning services.
The fire protection systems in the building were subjected
to overhaul to ensure these critical systems can continue
to perform at their optimum level. Key aspects of these
works were the change of all fire phones, sprinkler heads
and tanks and refurbishment of the main sprinkler pumps
in the building.
A number of important electrical upgrades formed a
substantial share of the phase 2 works in which the
two occupiers’ life safety generators were replaced
in their entirety and the four landlords’ generators
were fully reconditioned. Temporary generators
were installed and operated by Broadgate Estates
to maintain the level of backup power to occupiers
operations throughout the works.
Replacements to LV switchgear were undertaken where
ACBs (Air Circuit Breakers) had become obsolete and
unsupported with spare parts. Broadgate Estates also
managed the installation of a new load bank connection
facility as part of these works.
A number of temporary and permanent modifications
to the building were completed to enable the electrical
upgrades and to provide safe access routes for
occupiers during the works.
Several other restoration works were accomplished within
the programme including the replacement of all dry riser
landing valves and the refurbishment of passenger and
goods lifts and the two main AHUs. Upgrades were made
to the LTHW boiler system to transform the boiler burners
to flame controlled burners resulting in improved efficiency.
6
7. 1.3 Project governance
The responsibility of overall project
delivery was held by an incumbent Project
Lead who also provided immediate
client oversight. A Project Engineering
Director and a Project Client Director was
also appointed to provide engineering
oversight and client oversight respectively
and to be jointly responsible for approving
works and contracts. Any significant
variations to costs and timescales
were scrutinised and approved by the
Project Directors. In the occurrence
of considerable technical variations,
the Project Engineering Director was
responsible for approving the changes.
Systems upgrades and IT and fabric
related works were managed by three
appointed project managers from the
respective departments within Broadgate
Estates. The project team also included
a Manager who ensured compliance of
the programme with CDM (Construction,
Design and Management) regulation.
A clear communication plan was vital
in carrying out works within timescales
and budgets with minimal interruption
to the multiple client operations in the
property. A building management meeting
and an occupiers’ meeting held on a
weekly basis and a landlord’s meeting
held every month were crucial elements
of the communication plan. A six weekly
programme which was updated on a
monthly basis was presented by Broadgate
Estates to stakeholders during these three
types of meetings.
1.0INTRODUCTION
7
WEEKLY MEETINGS MONTHLY MEETINGS
1.0INTRODUCTION
7
9. 2.0PHASE1
9
The most significant part of Phase 1 was to refurbish the
N+1 resilience cooling system which provides cooling to
the occupiers’ UPS facilities.
The refurbishment of this critical system was
carried out with the collaboration of three specialist
contractors working simultaneously whilst the building
was fully occupied.
The UPS cooling system consists of a Carrier 30HXC230
Chiller located within the basement and a ground floor
chiller which provides N+1 resilience. The system works
in conjunction with a dedicated cooling tower.
The most critical aspect of the works was the replacement
of the carrier chiller. Additionally the ground floor chiller
and the cooling tower were fully refurbished in order to
extend their service life.
Broadgate Estates ensured the work did not compromise
the cooling requirements and cooling system resilience
of the UPS system by installing and operating an equally
sized temporary AC plant with air cooled chillers housed
in the loading bay.
Furthermore the fan control strategy for the cooling
tower was upgraded from two speed control to fully
modulating control resulting in increased efficiency.
Changes were also made to the BMS to increase the
frequency of flushing to protect the tower should the
system not run for the preceding 12 hours.
Previous to the change, condenser flushing was
accommodated in a single time zone each day.
The set point temperature to enable the cooling tower
fan was also decreased from 24ºC to 18.5ºC.
2.1 N+1 resilience system
10. 10
A complete replacement of the two chillers supplying
the sixth floor was carried out whilst the floor remained
fully occupied.
The new chillers were assembled on site within the plant
rooms whilst full cooling to the floor was maintained
using temporary chillers.
The temporary chillers were lifted by crane on to the
roof of the building and placed on a purpose built steel
structure for the duration of the works. These were
connected to the primary CHW circuit by temporary
flexible pipework which were fed through the roof and
seventh floor slabs.
Upon installation, the temporary system was tested
and commissioned before work started on the sixth
floor chillers.
One of the main challenges was the transportation of
the new chillers to the sixth floor plant rooms, which
was carried out by dismantling the units to manageable
sections and using the goods lift for transportation
between floors.
The old chillers were also transported from the sixth
floor to the ground floor using the same process.
The work was carefully co-ordinated and managed with
the contractor and the site M and E team to eliminate
the possibility of any disruption to the occupiers.
2.2 Sixth floor chillers
11. 2.0PHASE1
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A phased refurbishment programme was carried out for
all ten essential chillers on ground to second floor. This
included the replacement of all electronic monitoring
equipment, electronic switches, oil pumps and oil filters.
Furthermore the refrigerant volume and flow of the
systems were confirmed and the heat exchanger
internals were chemically cleaned using a flushing rig.
2.3 Ground to second floor chillers
The refurbishment process for each unit was concluded
by a comprehensive testing and commissioning
process. The chillers were refurbished to a carefully
planned schedule to ensure the cooling needs of the
occupiers were satisfied throughout the programme.
12. Broadgate Estates managed the refurbishment or replacement
of all 78 main pumps during the four-year programme to
ensure the units can perform effectively until 2019.
The pumps relate to all primary and secondary chilled water
and condenser pumps within the building. Each floor consists
of two primary chilled water pumps, eight condenser pumps
and eight secondary chilled water pumps.
Phase 1 addressed pumps on floors one to six with a particular
focus on third, fourth and fifth floors.
Some pumps were replaced in their entirety, whereas the
majority of pumps were refurbished.
Complete replacements were carried out for pumps that were
obsolete and unsupported by spares.
The pumps relating to refurbishment were initially assessed
to determine any components that required replacement.
Refurbishment consisted of replacement of seals, bearings,
O-rings, gaskets, motors and inverter drives.
Recognising the significant efficiency improvements that
can be realised, a number of bigger condenser pumps were
upgraded to inverter drives during the programme.
In order to minimise disruption and risk to the cooling
systems, the pump refurbishment programme was carefully
planned to match the cooling towers and chiller refurbishment
programmes that ran simultaneously.
Working in conjunction with the onsite M and E team, the
works were carried out successfully without any disruption to
the occupiers’ business.
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2.4 Pumps
13. 2.0PHASE1
13
2.5 Sprinkler heads
A substantial element of the renewal of the fire protection systems was
the replacement of all sprinkler heads in the property during the first
18 months of the programme. The key challenge was undertaking the
work in a property that was occupied with a number of floors housing
critical operations to occupiers’ businesses such as various trading
floors in the building.
Sprinkler replacements on occupied floors were carried out between
06.00pm and 03.00am to ensure no disruptions occurred and
sufficient time was available to prepare the floors ready for the
morning. An important aspect of the planning process was ensuring
all precautions were taken to eliminate the possibility of any impact on
occupiers’ property including highly sensitive and costly equipment.
The successful completion of the sprinkler replacement works
required careful planning and coordination and sound communication
between the site ME team and cleaning and fabric teams.
During the planning stage, each floor was divided into four quadrants
with work in each quadrant split further into multiple stages. Each
stage involved the replacement of around 30 sprinkler heads which
was typically completed within a single night shift.
Phase 1 of the programme incorporated the replacement of all 2,700
sprinkler heads from third floor to sixth floor which were fully occupied
during the works.
As Phase 1 was in progressions, the tenancy of ground, first and
second floors ended, which provided an opportunity to replace all the
sprinkler heads on these levels towards the latter part of phase 1.
Although not part of the initial plan for the programme, these works
were successfully incorporated to phase 1 works which resulted in the
renewal of all sprinkler heads in the building.
14. 14
A key part for the refurbishment programme of the cooling system was the
reconditioning of all cooling towers.
Broadgate Estates also utilised this programme to upgrade the fan motors to IP65
inverter driven motors. The 12 cooling towers in the building feeding the quadrant
condenser system were reconditioned over three phases to an equal standard.
This resulted in prolonging life, improving efficiency and ensuring protection against
waterborne pathogens.
The SE1, NE1 and NW3 cooling towers were fully refurbished during Phase 1.
A complete restoration of the fan sections was undertaken which included the
replacement of fan motors, wheels, shafts, bearings and couplings.
The infrastructure was also modified to support the new control strategy where new
pumps and brominators were fitted and an IQ enclosure for monitoring and fault
finding was manufactured and installed.
New wiring infrastructure including new screened power supply, control wiring and
network wiring were also installed for each cooling tower.
As part of the programme, components such as drive sets and belts, drift eliminator
media, fill packs, access door gaskets and float valve assemblies were also replaced
for all cooling towers.
Electrical aspects of refurbishment included renewing of local isolators and flange
boxes and other localised lagging repairs.
The work was carried out during normal working hours, without any compromise on
occupiers’ cooling needs. This was achieved by refurbishing one cooling tower from
each quadrant condenser system at a time; ensuring two units were always online to
fulfil cooling needs of the occupiers.
In addition to the phased mechanical and electrical works, various other works were
undertaken as detailed below.
2.6 Cooling towers
16. 16
2.7 Miscellaneous works
In addition to the phased mechanical and electrical works,
various other works were undertaken as detailed below:
2.7.1 Boiler Burners
In order to replace the obsolete burners for the two
LTHW boilers that provide underfloor heating for the
main atriums, the old burners were replaced in their
entirety with high efficiency flame controlled burners.
This was successfully carried out by the onsite M and E
maintenance team during the summer months to avoid
disruptions to occupiers’ heating.
2.7.2 AHUs
The on-site M and E service provider at 1-2 Broadgate carried out full
refurbishment of the two main AHUs located on the roof as part of
phase 1 of the programme to extend their life to 2019.
Works carried out on units include the overhaul of fans and fan drives,
replacement of filters, sensors, cleaning and lubrication of components
and treatment of corroded areas in the AHUs. A number of door hinges,
locks and seals were also renewed.
Units were then tested and commissioned and set back into operation.
17. 2.0PHASE1
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2.7.3 Dry Riser Valves
In order to ensure the dry riser valves are in their optimum
condition to support the fire services in an event of a fire,
all 32 dry riser landing valves in the building were fully
replaced. Additionally four inlet breeching valves and four
air release valves were also replaced.
2.7.4 Passenger and Goods Lifts
Broadgate Estates incorporated the refurbishment of
the lift motors and gearboxes of the four passenger lifts
and two goods lifts as part of the building infrastructure
works in Phase 2.
The lift motors in the passenger and goods lifts were
replaced due to their age which resulted in an extension
of life for the motors by 20 years.
Replacement of the gearboxes was a particularly
challenging aspect of these works as the original
and replacement gearbox assemblies had to be
disassembled for transport between floors due to
their size. The new gearboxes were reassembled
and commissioned in the lift plant rooms on the roof.
Arrangements were made by Broadgate Estates to
utilise a gearbox specialist from Germany to carry out
assembly and disassembly of gearbox units for each lift.
19. 3.0PHASE2
19
The generator project aimed to renew and refurbish the
generator units to increase service life to 2019 and to
realise additional benefits of improved resilience, reliability
and maintainability.
The most significant part of the project was the
replacement of two life safety generators in their entirety
and the reconditioning of four occupiers’ generators.
These works also included a pressure test of the
occupiers’ generator flues and a full function test.
In order to increase the life of the generator switch panels
to 2019, generator sync panels, switch panels and
switchboard components in a number of generator and LV
rooms were replaced.
Additionally BMS devices, software, hardware and
graphics were also upgraded to support the new and
refurbished generators.
Careful co-ordination and planning was required between
Broadgate Estates, the site maintenance team and the
contractor who carried out the work, in order to minimise
disruption or loss of backup power to occupiers and
to ensure N+1 resilience of the generator systems was
always maintained.
Broadgate Estates also ensured the building works
programme was planned to have the necessary walls
demolished to create access to remove the old generators
and deliver the new generators.
3.1 Generators
20. 20
Refurbishment of the LV switchgear included
the replacement of all Air circuit Breakers
(ACBs) and Moulded Case circuit Breakers
(MCCBs) within the old generator switch
boards.
The ACB and the MCCB ranges within the
old generator switch boards had become
obsolete and therefore replacements of
these units were carried out to ensure the
availability of spares beyond 2019.
Due to a number of incompatibilities
between the old and the new ACB ranges,
modification had to be made to the old
busbar connections to accommodate the
new units.
In order to eliminate any disruption to
occupiers’ operations, the ACB replacement
and load bank installation were completed
during weekend shutdowns.
3.2 LV switchgear
21. 3.0PHASE2
21
A load bank connection facility was installed to facilitate
individual testing of the landlord’s generators. This panel
provides simulated loads to allow the landlord to test
each generator at any one time. In the event of a mains
failure during such a test, the load bank automatically
switches off to allow the generators to provide backup
power to the property.
3.3 Loadbank
22. 22
The services of a specialist building works
company was needed to undertake
temporary and permanent modifications
to the building structure to satisfy access
requirements for the electrical works.
A number of walls and doorways of generator
rooms were demolished to remove old
generators from the building and to deliver
the new units.
Temporary walls and doorways were put
up to ensure access was permitted to
hazardous areas and safe walkways were
available for occupiers.
Additionally cladding was installed on
Finsbury Avenue which was painted and
illuminated to safely store the temporary
generators and load bank testing equipment.
Upon completion of the electrical upgrades, all
walls and doorways were rebuilt and the four
generator rooms were redecorated including
restoring walkways and floor markings.
Permanent changes to the building include
the holes formed through blockwork to
feed the loadbank busbar and cables,
modifications to the mesh cages to house
the new loadbank connection panels and
installation of fire cladding to all openings of
busbar and cables.
3.4 Building works
23. 3.0PHASE2
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3.5 Sprinkler systems
3.5.1 Sprinkler Pumps
The two main sprinkler pumps and the associated
jockey pumps serving the building were subjected
to a full refurbishment programme with the aim to
ensure this critical system is able to perform at its
optimum level.
3.5.2 Sprinkler Tanks
As part of the phase 1 works, all the sprinkler
tanks storing water in the basement were relined.
3.5.3 Fire Phones
All fire phones within the building were replaced
with new units in Phase 1. It was crucial to carefully
plan and manage this element of the programme
to ensure the large quantity of fire phones located
throughout the building were renewed using an
efficient and methodical approach.
24. 24
On continuation of the pump replacement and
refurbishment works, eighteen secondary chilled water
and condenser pumps on the ground to 5th floors were
addressed during phase 2.
The work done for each pump varied depending on
their condition.
Complete replacement was carried out for eight
pumps that were unsupported with spares with the
rest being refurbished.
New inverters were fitted for five of the refurbished
pumps and the remaining pumps were fitted with new
seals, gaskets and bearings. All pumps refurbished
were fitted with new motors.
Recognising the significant efficiency improvements that
can be realised, a number of bigger condenser pumps
were upgraded to inverter drives during the programme.
In order to minimise disruption and risk to the cooling
systems, the pump refurbishment programme was
carefully planned to match the cooling towers and chiller
refurbishment programmes that ran simultaneously.
Working in conjunction with the onsite M and E team,
the works were carried out successfully without any
disruption to the occupiers’ business.
3.6 Pumps
25. 3.0PHASE2
25
During phase 2, four more chillers
were subjected to refurbishment.
This included the replacement of all
electronic monitoring equipment,
electronic switches, oil pumps and
oil filters.
Furthermore the refrigerant volume and
flow of the systems were confirmed
and the heat exchanger internals were
chemically cleaned using a flushing rig.
The refurbishment process for
each unit was concluded by
a comprehensive testing and
commissioning process. The chillers
were refurbished to a carefully
planned schedule to ensure the
cooling needs of the occupiers were
satisfied throughout the programme.
3.7 Chillers
27. 3.0PHASE2
27
The refurbishment works for the cooling towers were
continued during phase 2 to fully restore three cooling
towers (i.e. SW1, NW1 NE3).
A complete restoration of the fan sections was
undertaken which included the replacement of fan
motors, wheels, shafts, bearings and couplings.
The infrastructure was also modified to support the new
control strategy where new pumps and brominators
were fitted.
New wiring infrastructure including new screened power
supply, control wiring and network wiring were also
installed for the cooling towers.
As part of the programme, components such as drive
sets and belts, drift eliminator media, fill packs, access
door gaskets and float valve assemblies were also
replaced.
Electrical aspects of refurbishment included renewing
of local isolators and flange boxes and other localised
lagging repairs.
The work was carried out during normal working hours,
without any compromise on occupiers’ cooling needs.
This was achieved by refurbishing one cooling tower
from each quadrant condenser system at a time;
ensuring two units were always online to fulfil cooling
needs of the occupiers.
3.8 Cooling towers
29. The pump replacement and refurbishment works were
completed during phase 3.
A similar approach to phase 1 and 2 was taken,
whereby each pump was assessed for replacement
requirements before replacing the required components.
Eight twinhead pumps on levels two, four and five
were addressed on this phase. Six of these pumps
were replaced and two were fitted with new seals and
O-rings. All pumps were fitted with new motors.
Recognising the significant efficiency improvements that
can be realised, a number of bigger condenser pumps
were upgraded to inverter drives during the programme.
In order to minimise disruption and risk to the cooling
systems, the pump refurbishment programme was
carefully planned to match the cooling towers and chiller
refurbishment programmes that ran simultaneously.
Working in conjunction with the onsite M and E team,
the works were carried out successfully without any
disruption to the occupiers’ business.
The refurbishment process for each unit was concluded
by a comprehensive testing and commissioning
process. The chillers were refurbished to a carefully
planned schedule to ensure the cooling needs of the
occupiers were satisfied throughout the programme.
4.1 Pumps
4.0PHASE3
29
30. In order to conclude the chiller refurbishment works, the
eight remaining chillers in the building were refurbished
using the same process used in the first two phases.
This included the replacement of all electronic monitoring
equipment, electronic switches, oil pumps and oil filters.
Furthermore the refrigerant volume and flow of the systems
were confirmed and the heat exchanger internals were
chemically cleaned using a flushing rig.
The refurbishment process for each unit was concluded by
a comprehensive testing and commissioning process. The
chillers were refurbished to a carefully planned schedule to
ensure the cooling needs of the occupiers were satisfied
throughout the programme.
4.2 Chillers
30
31. The final phase also involved the completion of the
cooling tower refurbishment works.
Six cooling towers (i.e. NE2, NW2, SW2, SW3, SE2 and
SE3) were fully refurbished in this phase.
A complete restoration of the fan sections was
undertaken which included the replacement of fan
motors, wheels, shafts, bearings and couplings.
The infrastructure was also modified to support the new
control strategy where new pumps and brominators
were fitted.
New wiring infrastructure including new screened power
supply, control wiring and network wiring were also
installed for the cooling towers.
As part of the programme, components such as drive sets
and belts, drift eliminator media, fill packs, access door
gaskets and float valve assemblies were also replaced.
Electrical aspects of refurbishment included renewing
of local isolators and flange boxes and other localised
lagging repairs.
The work was carried out during normal working hours,
without any compromise on occupiers’ cooling needs.
This was achieved by refurbishing one cooling tower
from each quadrant condenser system at a time;
ensuring two units were always online to fulfil cooling
needs of the occupiers.
Completion of these works ensured all the cooling
towers at 1 and 2 Broadgate are at an equal standard
with increased life, efficiency and protection against
waterborne pathogens.
4.3 Cooling towers
31
4.0PHASE3
31
33. CONCLUSION
33
Under the management of Broadgate Estates, the
refurbishment program of 1-2 Broadgate was delivered
before the scheduled completion date, significantly under
budget and without the occurrence of any safety incidents.
Though careful planning, coordination and a highly
client focussed approach, Broadgate Estates ensured
all building services to occupiers were maintained
throughout the program, without any compromise on
standards and resilience.
5.0 Conclusion
