Cork Airport Terminal Roof

1. 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 porta-cabins. 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 quality if it is designed well and procured in a sensible way. 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

2. 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.

3. 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.

4. 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.

5. 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.

6. 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.

7. 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.

8. 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.

9. 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

10. Questions? please contact Chris Bakkala Adelaide Chambers Peter Street Dublin 8 T 353 (0)1 449 3244 M 353 (0)87 415 8232 E chris.bakkala@walshgroup.eu.com or E chris@cbakkala.com