Prefabricated timber Pods, completed in the factory for use as second storeys on homes and transported by semi-trailer for erection by crane on site, is the latest construction concept to take a rapid hold in the Western Australian residential building market.
The Pods have been developed and engineered by Pryda in conjunction with one of its leading West Australian fabricators, W.A. Spantruss.
The first company to trial the concept was Perth project home builder 101 Residential. So far, the company has used 30 Pods with another 60 in the pipeline for its various projects throughout the city.
101 Residential is so impressed with the Pods it is using them on display homes to attract further business, so far with considerable success. Several other builders have also shown keen interest in the concept.
Dave Lewis of W.A. Spantruss said the biggest advantage of the new Pods was the significant cost reduction and weeks it saved in construction time on conventional building methods particularly as no scaffolding was required to erect them.
Introduced to the Western Australian market in July last year, Pod sizes start at six metres by six metres (essentially used for upstairs studios), which saves about three to four weeks in construction time,” he said. However, the larger the Pod, the greater the time saving.
As the idea has grown in popularity, so have Pod sizes. The latest W.A. Spantruss effort is a 110-square-metre module (eight-week construction saving).
Pryda Market Development Engineer Bernard Kennelly said in Western Australia most houses were built from double brick which meant, for two storeys, stronger and heavier footings and bricks were required to take the weight of the second storey concrete slab floor.
The new and lighter Pods dispense with the need for these extra precautions. he said. The Pods used Pryda Longreach for the second storey floor trusses (which also act as the ceiling joists for the first floor) and Pryda prefabricated roof trusses and timber wall frames.
One of the biggest hurdles in development was to match the accuracy of the factory built Pod with on site brickwork, which may not be constructed to the same exacting dimensions.
To overcome this and to allow extra flexibility on site, WA Spantruss and Pryda use structural steel support beams between the top and bottom chords of the Pryda Longreach floor trusses.
A number of webs within the Pryda Longreach floor trusses are moved to accommodate the steel beams and duct spaces. The duct spaces run the full length of the Pod and enable the easy fitting of air conditioning ducts and plumbing and electrical services.
There is only a minimum number of support positions on site that need to be level for the Pod to fit, Bernard said. We don’t need to worry too much where the walls are located because, as long as one of the internal supports is under a steel beam, the whole process will work.
With 75mm EPS wall sheeting, windows, gutters, fascias, eaves, roof battens, linings and insulation all installed in the factory, the house can quickly be brought to lock up stage once the Pod is delivered to site.
Bernard said because of the heavy construction involved in two-storey buildings, West Australian builders were used to having cranes on building sites.
Normally, we crane the Pods into position in two halves and then join them together when they are in place, he said.
Irrespective of the Pod size, the installation process takes no more than a couple of hours. Any final finishing, including the fitting of down pipes, hiding the joins in the Pod construction, can be easily and quickly completed on site.
For further information contact Bernard Kennelly at Pryda Australia on (02) 8811 6900.