The challenges provided by large commercial jobs and Multi-Residential Timber Framed Constructions (MRTFC’s) are many, but advances in timber engineering are seeing some surprising results -once considered the sole domain of steel.

Timber construction is considerably cheaper than steel and, in some instances, far more versatile. Add wall frame prefabrication to the equation and the advantages for the architect, builder and developer can be substantial.

Bowens Roof Trusses in Dandenong (and Hastings), on the outer fringes of Melbourne embrace both roof truss and wall frame manufacturing and see them as vital to both their success and that of their clients; a recent (85 bed) Aged Care Facility in Eden, NSW is testament to that.

What first appeared to be, a fairly straight forward job from the architect’s seemingly simple plans, held a few engineering challenges. There was the unique roof design, complete with unusual roof planes and large overhangs; creating several issues -mainly involving the size of timbers used and uplift considerations.

The facility comprises three long buildings running parallel to each other, with a central reception and work station containing the operations and administrations areas. The roof is fairly flat but tapers at various points. Trusses were as shallow as 500mm at one end and 2.5m at the other, with overhangs stretching almost 3m beyond external brick walls.

In addition to those variances, box guttering ran diagonally through the roof lines, requiring beams either side to support the trusses. The web layout of the trusses had to be configured in such a way as to ensure free-flowing channels for services; most of which were to run in the roof as the whole project was built on a concrete slab.

Jim Raso, In Charge of commercial detailing at Bowens, said that the roof comprised of nearly 1,000 trusses and about 900 of them were one-offs, The client needed the job delivered in specific stages, all by truck; a mere 10 hour drive down the road. Some of the trusses were nearly 10m long and more than 2.5m high. Bowens are geared up to meet even the most demanding challenges.

Colin Garrett looked after the detailing of wall frames and shed more light on the enormity of this job. Wall frame production on the Eden project used almost double the timber required for the roof trusses (126m3), resulting in 2,400 lineal metres of frames.

Jim and Colin Garrett work side by side on most projects, constantly cross-referencing everything to make sure every aspect of every job is engineered perfectly. They will also make several trips on-site to ensure no stone is left unturned for their clients. The advantages of being able deliver ‘the complete fabrication package’ to clients are very clear to Colin.

According to Colin quality product and relationship building go hand-in-hand in this business. The more the clients look to Bowens for solutions, the stronger their bond grows. Bowens’ clients are subjected to increased deadline pressures and prefabricated (engineered) wall framing is helping them on-site in more ways than one.

Amazing advances in timber engineering enable Architects, Builders and developers to put timber prefabrication as their first choice for those challenging designs, especially when it comes to dynamic, often unorthodox roof lines.

However in both the domestic and commercial markets, the prefabrication of wall frames is often overlooked. The advantages are becoming more and more difficult to ignore though as increased demands on builders and developers to meet tighter deadlines increases.

The ability to provide architects, designers and builders with a ‘one-stop-shop’ solution where both prefabricated wall frames and roof trusses are sourced from the one supplier can result in noticeable advantages on-site.

With construction deadlines a priority, the ability to prefabricate wall frames is emerging as a more and more attractive way to build. For builders and developers prefabricated wall frames are quicker to install than the ‘build from scratch’ option.

Prefabricated wall frames have been known to actually halve the time required on-site for erection. This means there is less time on-site required for carpenters and builders, an added advantage in reducing costly man-hours.

Prefabricated wall frames are also a great way to ensure consistency of quality, and that the wall frames have been properly engineered to meet specific load, wind-bearing and bracing requirements.

Being a licensed MiTek Australia fabricator, Bowens Roof Trusses have access to MiTek’s powerful 20/20 and AutoBeam programs. This allows Bowens to provide customers with designs for optimum construction efficiency and quality engineering, all while ensuring Australian Standards are met, every time.

An example of roof truss and wall frame prefabrication can be found at a new Aged Care Facility in Eden, NSW.

  • Suppliers of roof trusses and wall frames: Bowens Roof Trusses
  • Software for Roof Trusses: MiTek 20/20
  • Software for Wall Frames: MiTek 20/20 Panel & AutoBeam

Following are the advantages of roof truss and wall frame prefabrication:

  • Engineered solutions
  • Consistency of quality
  • One-stop-shop supply
  • Speeds-up construction