Dr f Dejahang (BSc CEng, BSc (Hons) Construction Mgmt, MSc, EX MCIOB EX........ PhD

1. OFFSITEOFFSITE
MANUFACTUREMANUFACTURE
PRECAST FRAMESPRECAST FRAMES
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2. OFFSITEOFFSITE
MANUFACTURE(OSM)MANUFACTURE(OSM)

3. OFFSITEOFFSITE
MANUFACTURE(OSM)MANUFACTURE(OSM)
Categorisation of OSMCategorisation of OSM
Volumetric systemsVolumetric systems
Majority of factory-based form ofMajority of factory-based form of
production, volumetric systemsproduction, volumetric systems
involve three dimensional modulesinvolve three dimensional modules
that can be used in isolation or inthat can be used in isolation or in
multiples to form the structure of themultiples to form the structure of the
building.building.

4. OFFSITEOFFSITE
MANUFACTURE(OSM)MANUFACTURE(OSM)
These modules can be pre-These modules can be pre-
finished in the factory.finished in the factory.
They include all fixtures andThey include all fixtures and
fittings, requiring a very limitedfittings, requiring a very limited
amount of installation work onamount of installation work on
site.site.

5. OFFSITEOFFSITE
MANUFACTURE(OSM)MANUFACTURE(OSM)
Open panel systemsOpen panel systems
Open panel systems are typicallyOpen panel systems are typically
delivered to the site purely as adelivered to the site purely as a
structural element with services,structural element with services,
insulation, cladding and internalinsulation, cladding and internal
finishes installed in situ.finishes installed in situ.

6. OFFSITEOFFSITE
MANUFACTURE(OSM)MANUFACTURE(OSM)
Closed panel systemsClosed panel systems
 These are similar to open panel systemsThese are similar to open panel systems
in that the structural elements of thein that the structural elements of the
building are delivered to the site in flatbuilding are delivered to the site in flat
panels.panels.
 Closed panel systems include moreClosed panel systems include more
factory based fabrication such as liningfactory based fabrication such as lining
materials and insulation.materials and insulation.

7. OFFSITEOFFSITE
MANUFACTURE(OSM)MANUFACTURE(OSM)
 It may also even include:It may also even include:
 CladdingCladding
 internal finishesinternal finishes
 ServicesServices
 doors and windowsdoors and windows

8. OFFSITEOFFSITE
MANUFACTURE(OSM)MANUFACTURE(OSM)
Hybrid systemsHybrid systems
 A combination of volumetric and panelisedA combination of volumetric and panelised
systems.systems.
 The high value areas such as kitchen andThe high value areas such as kitchen and
bathroom are typically formed frombathroom are typically formed from
volumetric units.volumetric units.
 The rest of the structure formed fromThe rest of the structure formed from
some form of framing system.some form of framing system.

9. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 UK’s off-site manufacturing (OSM)UK’s off-site manufacturing (OSM)
industry in relation to the supply of OSMindustry in relation to the supply of OSM
components for housing.components for housing.
 Almost any component can beAlmost any component can be
manufactured off site.manufactured off site.
 Reinforced concrete columns (circular orReinforced concrete columns (circular or
square) with a smooth even surface readysquare) with a smooth even surface ready
for direct decoration.for direct decoration.

10. OFFSITE MANUFACTUREOFFSITE MANUFACTURE

11. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
Beams and floorBeams and floor
 Like the other structural elements beamsLike the other structural elements beams
and floors.and floors.
 Units can be designed to meet client’sUnits can be designed to meet client’s
requirements making provision forrequirements making provision for
services or features that will beservices or features that will be
incorporated during manufacture.incorporated during manufacture.

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13. OFFSITE MANUFACTUREOFFSITE MANUFACTURE

14. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Parapets are often a very visible elementParapets are often a very visible element
of the structure making their aestheticof the structure making their aesthetic
appeal as important as their structuralappeal as important as their structural
integrity.integrity.
 Barriers can be supplied with a variety ofBarriers can be supplied with a variety of
attractive concrete finishes or designed toattractive concrete finishes or designed to
allow materials used elsewhere in theallow materials used elsewhere in the
structure, such as brick or stone to bestructure, such as brick or stone to be
incorporated.incorporated.

15. OFFSITE MANUFACTUREOFFSITE MANUFACTURE

16. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
Double Tee BeamsDouble Tee Beams
 Providing a lightweight solution for longProviding a lightweight solution for long
spans;spans;
 Double tee beams can reduce the numberDouble tee beams can reduce the number
of columns needed which is ideal for carof columns needed which is ideal for car
parks and offices.parks and offices.
 Using steel moulds for a smooth, evenUsing steel moulds for a smooth, even
finish Double Tee Beams arefinish Double Tee Beams are
manufactured to BS8110.manufactured to BS8110.

17. OFFSITE MANUFACTUREOFFSITE MANUFACTURE

18. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
Using concrete structuralUsing concrete structural
elements offers:elements offers:
fast track, off-sitefast track, off-site
construction, even for largeconstruction, even for large
structures.structures.

19. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
Coffered Flooring UnitCoffered Flooring Unit
 These carefully detailed units provide aThese carefully detailed units provide a
flooring slab incorporating a finishedflooring slab incorporating a finished
ceiling.ceiling.
 The units can be manufactured to theThe units can be manufactured to the
designer’s specification incorporatingdesigner’s specification incorporating
whatever details are required.whatever details are required.

20. OFFSITE MANUFACTUREOFFSITE MANUFACTURE

21. Ground BeamsGround Beams
concrete beamsconcrete beams
provide a strong, durable structural element capableprovide a strong, durable structural element capable
of providing many years ofof providing many years of trouble free servicetrouble free service

22. Wall PanelsWall Panels
Precast wall panels are manufactured to client'sPrecast wall panels are manufactured to client's
specification. They are suitable for use in multi-storeyspecification. They are suitable for use in multi-storey
construction and when combined with precast floorsconstruction and when combined with precast floors
allow a building to be erected very quicklyallow a building to be erected very quickly

23. Terrace units can be used anywhere wereTerrace units can be used anywhere were
banked seating is required from stadia tobanked seating is required from stadia to
concert halls.concert halls.

24. Lift ShaftsLift Shafts

25. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Manufactured off-site in bespoke mouldsManufactured off-site in bespoke moulds
and installed quickly and efficiently by theand installed quickly and efficiently by the
specialist installation teams.specialist installation teams.
 Rigorous quality control will ensure that allRigorous quality control will ensure that all
components are accurate, eliminatingcomponents are accurate, eliminating
problems on site.problems on site.

26. OFFSITE MANUFACTUREOFFSITE MANUFACTURE

27. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Every bridge is unique and will require aEvery bridge is unique and will require a
design solution developed to meet all ofdesign solution developed to meet all of
the requirements of the project.the requirements of the project.
 From the ground conditions andFrom the ground conditions and
specification of the bridge to the logisticsspecification of the bridge to the logistics
dictated by the site and the potentialdictated by the site and the potential
disruption of such a major project.disruption of such a major project.

28. OFFSITE MANUFACTUREOFFSITE MANUFACTURE

29. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
AdvantagesAdvantages
 Off-site construction allows the buildOff-site construction allows the build
process to run concurrently can equate toprocess to run concurrently can equate to
as much as 60% reduction in programmeas much as 60% reduction in programme
 Off-site construction offers improvedOff-site construction offers improved
building quality due to the controlledbuilding quality due to the controlled
construction environment i.e. factory finishconstruction environment i.e. factory finish
and turn-key solutionand turn-key solution
 Cost certainty for ClientCost certainty for Client

30. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Reduced waste (off cuts, packaging etc) –Reduced waste (off cuts, packaging etc) –
new legislation in the UK forcesnew legislation in the UK forces
construction clients, designers andconstruction clients, designers and
contractors to adopt a more sustainablecontractors to adopt a more sustainable
approach to waste.approach to waste.
 Off-site construction facilities are enclosedOff-site construction facilities are enclosed
and secure protecting against weatherand secure protecting against weather
damage and delaysdamage and delays
 as well as theft.as well as theft.

31. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Permanent, long term employment forPermanent, long term employment for
skilled labour both within the factory andskilled labour both within the factory and
engineers on site.engineers on site.
 Improved Fire/Acoustic performanceImproved Fire/Acoustic performance
(effectively two walls between all rooms(effectively two walls between all rooms
with a cavity)with a cavity)
 Improved Thermal EfficiencyImproved Thermal Efficiency

32. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
SafetySafety
 Reduced number of workers/man hoursReduced number of workers/man hours
on siteon site
 Workers have a reduced number of tasks /Workers have a reduced number of tasks /
hazardshazards
 System building allows detailed analysis ofSystem building allows detailed analysis of
risks at each stagerisks at each stage
 Less noise, dust and general disturbanceLess noise, dust and general disturbance
 Fewer commercial vehicle movementsFewer commercial vehicle movements

33. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
DisadvantagesDisadvantages
 Economically efficient for repetitive floorEconomically efficient for repetitive floor
plates onlyplates only
 Most off-site modular systems are limitedMost off-site modular systems are limited
to low-rise due to structural stability ofto low-rise due to structural stability of
modulesmodules

34. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Modules are limited in size by transportModules are limited in size by transport
legislation and width of delivery vehicleslegislation and width of delivery vehicles
 Preferred sizes (but larger sizes /heightsPreferred sizes (but larger sizes /heights
are common)are common)
-Width 4.0m outer face of floor steel-Width 4.0m outer face of floor steel
- Length 10.6m outer face of floor steel- Length 10.6m outer face of floor steel
- Height 2.8m floor to floor- Height 2.8m floor to floor

35. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Design freeze required early in the project.Design freeze required early in the project.
 VMS System is 18 weeks prior toVMS System is 18 weeks prior to
scheduled delivery on site.scheduled delivery on site.
 Size of crane required to lift modules maySize of crane required to lift modules may
not be cost effective with smallernot be cost effective with smaller
quantities’quantities’

36. OFFSITE MANUFACTUREOFFSITE MANUFACTURE
 Transportation can be costly if site isTransportation can be costly if site is
remote, significant distance from factoryremote, significant distance from factory
and if loads are wideand if loads are wide
 No flexibility or option for future adaptationNo flexibility or option for future adaptation