The LifeCycle Tower project aims to demonstrate the feasibility of a 20-story timber high-rise building through detailed design. Some key goals are to maximize off-site prefabrication, provide flexible interior spaces, and promote sustainable design with minimal carbon footprint while meeting performance requirements. The proposed design uses a solid cross-laminated timber core and perimeter columns with composite concrete-timber slabs. Modular construction techniques are emphasized. The project addresses challenges like fire safety through the core concept of protected stairwells and pressurized compartments.

1. LifeCycle Tower
Timber high-rise research project
George Faller and Martin Unger

2. LifeCycle Tower
 Why timber ?
 Why not timber ?
 Unlocking the potential for structural timber
 The LCT project – aims and characteristics
 Technical developments
 Fire safety design
 Why timber
2

3. LifeCycle Tower
Why timber ?
3

4. LifeCycle Tower - Introduction
Timber as a structural material
Difficult to find a more traditional
structural material than timber
5-10% share of construction market
Decline in 20th century, replaced by concrete
and steel
Sustainable solutions for buildings
Timber 100% renewable
Zero carbon emissions (carbon sink)
Low embodied energy
Sustainable in all phases of life cycle
4

5. LifeCycle Tower – the life cycle
manufacturing
process
Cut raw material and
processing, also for
generating energy procurement
Transport and
construction
use
lifetime use,
maintenance and
repair
demolition
Recyling and disposal
source : institute for energy efficiency – lecture 11. timber construction forum
5

6. LifeCycle Tower – construction comparison
Example:
Grimme-School in Brakel GWP (100)
[Source: TU Dresden – lecture 11. timber
construction forum – Prof. Haller]
Reinforced concrete Timber
crude oil [t] 2.040 t 470 t
GWP (100) 54.000 kg - 41.500 kg
negative emission - means that
CO2 is saved and not released.
6

7. LifeCycle Tower
Why not timber ?
7

8. LifeCycle Tower – negative perceptions
FIRE
Why not build more
in timber?
Infestation
Tradition
Cost
Risk
Discussion,
Strength
arguments,…
Durability
8

9. LifeCycle Tower – consequences
Perceptions of timber
Historical perceptions persist
 Great Fire of London 1666, Chicago in 1871, .....
Limitations – 2nd rate structural material
 Code limitations on max height of timber buildings
 Timber associated with low rise
 Little knowledge of timber for more demanding structures
9

10. LifeCycle Tower – Performance Based Design
“The building should be designed and
constructed so that, in the event of fire,
its stability will be maintained for a
reasonable time,.... ...., as well as to allow
fire fighters to operate.”
removed code imposed
height limits for timber
construction
10

11. LifeCycle Tower – the Consortium
The objective of this study was to demonstrate the feasibility of a
commercial timber high-rise construction of 20 storeys in a
densely populated urban context at detail design level.
project sponsored by
the Federal Ministry of
Traffic, Innovation and
Technology (BMVIT)
within the ‘house of the
future’ program
11

12. LifeCycle Tower – sceptics
Oxygen stream to the discussion
timber after the glazing
has broken
Defining of the
objective of protection
Who takes
responsibility for the
Timber carries on approval on behalf of
What happens to the holes and burning after 90min the Authorities?
openings, when the next tenant
moves in? Will the fire safety How could the timber buildings
measures still be effective? develop outside of the big cities?
discussion: fire protection Vorarlberg Bregenz and ETH Zürich Prof. Fontana
12

13. LifeCycle Tower – Fundamental research issue
equivalent level
of safety – timber
compared with
concrete or steel
objectives
Maximise the amount of off-site prefabrication
Maximum flexibility of internal space
Promote sustainable design, minimise the carbon footprint
no compromise on performance
13

14. LifeCycle Tower – building characteristics
The LCT building design
20-storey high building
Bottom 2 floors conventional construction
Footprint of 27m wide x 43m long
Building height 70m, 3.5m floor-to-floor
Use as offices, apartments or hotel
Structural concept
Nucleus of solid load bearing CLT panels
Solid timber perimeter columns on 2.7m grid
Composite concrete-timber slab construction
Span 11.3m; nucleus to perimeter columns
14

15. LifeCycle Tower – modular construction
Prefabrication
cores, ceiling and facades will be
delivered prefabricated
Source : Renderings from creebyrhomberg
15

16. LifeCycle Tower – the LCT-design
dynamic examinations
of the bracing system
- according to ISO 6897
Internal solid timber core
- according to NBCC
consist of vertically installed
- significant: sense of comfort gluelam beams
in the hotel and living use as overall stiffening system
Vertical load transfer from Horizontal loads (wind) are
slab elements via timber transferred by continuous
façade columns and concrete layer of the composite
timber core slabs into timber core
16

17. LifeCycle Tower – the LCT-design
concrete ceiling
(140mm)
gluelam beam
(80 and 160mm)
Construction steps:
1. Erection of gluelam core
elements (height approx. 30m)
2. Installation of façade (twin)
columns for one level
3. Build in timber-concrete
composite slab elements timber column
between core and columns (240 x 500mm)
4. Repeat steps 2 and 3…
17

18. LifeCycle Tower – the LCT-design
structural shell
of the building
18

19. LifeCycle Tower – the LCT-design
interior design
of the building
Source : Renderings from creebyrhomberg
19

20. LifeCycle Tower – the LCT-design
mass burning rate
separation
exposed
normally 0,6-0,8mm/min at first protected
(according to type of degree depends on
timber and point of casing type
action)
after the
plasterboard burned
away, the mass burning
rate is almost twice the
normal rate, until the
charcoal layer is about
20mm
20

21. LifeCycle Tower – core concept
concept –
ground area
step – core
fire lift and 2 protected
safety stair cases each
with pressurization and
lobby, no combustible
surfaces
21

22. LifeCycle Tower – concept (isolation)
European K2 90 is
not regulated in the
EN 14135 fire
protection casing
In the Swiss fire protection
regulations VKF casing with
fire resistance capability is
called EI 30 (nbb) up to EI 90 GL24h wooden
(nbb) plywood wall size
12 – 30 cm
Source : Lignum-documentation fire protection 9.1 fire break wall construction REI 90, SIA Lignum
22

23. LifeCycle Tower – concept
concept –
ground area
step – protected
corridor
peripheral protected
corridor, separated into
2 smoke compartments,
non-combustible
surfaces
23

24. LifeCycle Tower – concept
The timber beams for the
composite slabs are
interrupted in the area of the
necessary corridors, to create
an installation zone with non-
combustible exterior walls.
24

25. LifeCycle Tower – concept
concept –
ground area
step – use
Area of use and use
units, wooden parts of
the load-bearing
construction in timber
visible and not isolated.
25

26. LifeCycle Tower – beam-development
oxygen stream
caused by
destroyed
facade
Quelle :
26

27. LifeCycle Tower – building and use
Vertrieb- und
sale and use
Verwendung
transport and building
Transport und
Bauwerkserstellung Nutzung
use
Betrieb,
in use, maintenance
Instandhaltung und
and repair
Instandsetzung
Source : Institut für Energieeffizienz – Vortrag 11. Holzbauforum
27

28. LifeCycle Tower – quality management
example – quality
management
The Swiss regulate the QM over the Lignum code.
Standard: Building with wood – quality safety and
fire protection. For the research project a quality
management analog to the quality control at step 4
in the Lignum documentation fire protection is
intended. The quality management spans the design,
prefabrication, montage and building phases as well
as the organizational fire protection regulations in
later use. The quality characteristics are determined
by the project design, production conditions and
conditions at site. Source : Lignum-documentation fire
protection, - building with wood –
quality safety and fire protection
28

29. LifeCycle Tower – building site fire protection
danger
• higher risk for fire
• storage of combustible materials
• visible timber framework
risk
highest risk for fire in the first step of the
construction
measures
• module-system, prefabrication
• reduced individual work of tradesman
• minimized storage
• short building time
• avoiding the visible timber framework
29

30. LifeCycle Tower – Recyling
ceiling fire experiment
according to EN 1365-2
Banana effect – peeling of the single layers
of the gluelam beams did not occur during
fire test
30

31. LifeCycle Tower – final words
Why?
Because…
 we wanted to be economical with
resources
 timber is CO2 neutral
 the modular building system is much
faster
 a high quality of elements could be
guaranteed through significant
prefabrication
………..
31

32. LifeCycle Tower
Thanks
for your attention
George Faller
Leader Arup Fire Europe
george.faller@arup.com
Martin Unger
Leader Arup Fire Germany
martin.unger@arup.com
32

33. 33