Transcript Timber - Bakkala Consulting Engineers

In most parts of the world Timber construction enjoys a reputation for quality and beauty, but in
Ireland and the UK it is often perceived as a cheap, low quality solution used mainly for portacabins. Often cited as a ‘sustainable’ material, timber has also seen widespread inappropriate
use as an external finish in certain high maintenance, fast ageing situations that result in
decidedly unsustainable performance.
However, Timber construction in Ireland can be inexpensive and of high
is designed well and procured in a sensible way.
quality if it
Appropriate design for the material, such as provision of robust and complete damp protection
at wall base plates, or the careful design and specification of structural connections, will help
to ensure a structure as durable as any engineered building frame. Adequate design
coordination and follow through with site supervision will help preclude the urge for on-site
modifications with a chain saw to produce high quality buildings that perform as intended.
Following are some projects I have been involved in recently at Buro Happold which we
designed using structural timber and some thoughts on how it might be better deployed in
future to provide economical solutions of lasting quality.
- Chris Bakkala
Cork Airport
Terminal Roof
A complex
engineered timber
and steel
composite
bowstring beam
design, it was
procured by a main
Contractor through
a timber fabricator
with the steelwork
subcontracted
through the Timber
Lead.
Rehan Electronics Factory, Carnew, Co. Wicklow
Round pole timber roof
trusses self-built by an
owner-occupier using direct
labour.
The logs were procured
through an Irish timber mill
which sourced the material
in Latvia.
The timber is of very high
quality; it is normally used
for telegraph poles, but kiln
drying was modified and
preservative treatment
eliminated for this internal
application.
Triangular trusses provided
a path for natural day
lighting of the factory
assembly hall.
The Daintree Building, Dublin
Now about 3 years old,
this building was
intended to serve as a
model of sustainable
construction. It
comprises three
storeys of apartments
on a single storey
commercial level over
a single basement
level.
A concrete frame was
used up to first floor
providing fire
separation to
residential
accommodation
above.
The 3-storey timber
frame was delivered to
a tight inner city site as
flat-pack panels for
erection, cladding and
fit-out.
Alzheimer Centre, Blackrock
Flat pack 1-storey timber frame
saved several hundred thousand
euro off the original price tag
allowing this very highly detailed
building to get built.
Community healthcare facilities are
a niche market where timber frame
construction offers excellent value
for money spent toward achieving a
comfortable internal environment.
Griffeen Valley School, Lucan
This two storey building is constructed largely from site-erected flat
pack timber panels with the exception of the first floor structure.
In response to a client desire for concrete floors hollow core
precast plank on a steel frame was used for the first floor
construction. This required the timber frame contractor, who was
performing as a main contractor, to procure key critical path
components from specialist suppliers.
While this project was successfully delivered on a fast track,
programme and cost would have seen significant benefits from
elimination of structure subcontracts.
Composite Concrete
and timber floors
combine the economy
of timber with the
performance of
concrete.
Multi storey timber framed buildings
with composite concrete floor slabs
enable concrete floor construction
to be integrated with erection of the
pre-fabricated timber frame without
the cost and lead time required for
off site prefabrication by specialist
subcontractors.
While this type of construction is
not uncommon in Europe and North
America, often finding application in
the upgrade of historical buildings,
it is virtually unknown in Ireland.
Composite concrete and timber
proved a successful approach to
stiffening the floor of the RIAI café
in Merrion Square within the
constraints of the floor thickness
defined by the historical finishes.
Among conventional
construction materials, timber
construction provides the
lowest embodied energy.
Timber construction stores
carbon, sequestering it away
from the Carbon Cycle.
Materials such as cellulose
insulation can provide further
reduction to CO2 construction
footprint, while reducing
energy consumption over the
life of the building.
Factory-controlled
production using
simple dimension
timber or engineered
timber products can
provide simple, open
plan structures of high
quality.
Timber stud wall
panels sheathed in
Irish OSB
Panel construction in the factory, shipment to site, and site assembly by Cygnum
Questions?
please contact
Chris Bakkala
Adelaide Chambers
Peter Street
Dublin 8
T 353 (0)1 449 3244
M 353 (0)87 415 8232
E [email protected]
or
E [email protected]