On Thursday the 19th of September a group consisting of Building Designers, Builders, Engineers and Thermal Performance Assessors from the local area with a couple from Melbourne were treated to a very informative tour of the XLam plant organised by Sherlyn Moynihan from Design Matters and Anthony Antonino from XLam.
The timber used in the panel production is radiata pine from the Tumbarumba NSW Hyne timber mills. It is a lower grade than the MGP10 but don’t think that makes it a poorer quality product, the process and high tech equipment checks every stick of timber for moisture content quality and grain orientation and is photographed. Moisture content is
12 to 16% for those who like the detail.
The timber has defects removed, planed, finger jointed, trimmed and orientated to the optimal grain direction, glued, layered then subjected to pressure in a large press.
Finally entering a huge CNC machine to be cut to order before packing and shipping. Each panel is specifically designed for purpose. This can be anywhere from 3 to 9 layers. The majority of production is 3 to 5 layers. The biggest panel they can manufacture is 3.4m by 16m however transport and site constraints will determine the shipping size.
Every panel has three samples cut from it for photographing, testing and storing. Two are subject to wet and dry testing, simulating 50 years of life, to make sure there is no
delamination, the other sample is stored for 7 years. 99% of panels are passed as acceptable. Anthony conveyed a real sense that quality is important to XLam as they know they are
pioneers for the product in Australia.
Currently treated and un-treated panels are made though Anthony did say they may move to all treated in the future. Looking around the factory there didn’t seem to be much waist.
Reject timber that is too high in moisture goes back to the mill, timber that is too dry is discarded and can be used for other purposes. The sawdust from the CNC machine, a mix of treated and un-treated timber is a waste product.
XLam doesn’t have storage facilities so project timing is very important. While we were there some panels were being wrapped in a breathable moisture proof wrap, not something
they normally do but obviously an option at an addition cost.
CLT panels are not a product you will buy off the shelf, all projects are specifically designed and engineered. Construction methods are also specific to the project. To quote
Anthony, “You can’t just go to Bunnings and buy screws and fixing brackets off the shelf”.
The product is not aimed at the general housing market but may be ideal for multi-story residential units or commercial projects and possibly for difficult sites. CLT is not competing with the stud frame wall but more the tilt concrete panel. For interest I did a quick calculation and found the amount of timber used in say a residential project could be anywhere from 2 to 5 times more depending on where it was used. Great for locking up carbon but an added expense that would not be attractive to the project home market. However, for the right project a design employing CLT’s excellent structural properties, for example a wall frame that also serves the purpose of a structural beam, will make it very attractive, along with the speed of construction with floor, wall and roof panels being craned into place.
XLam provide help in the design process and recommends they be contacted early to ensure the design makes the most of the CLT product in terms of economics, structural design
and construction sequencing. There are currently no Australian Standards for this type of construction. It must be treated as a performance measure under the NCC. XLam can help with supporting technical documentation for the performance requirements.
The very modern Wodonga plant employees 30 people, and personally I’m pleased to see this in a regional area. The tour was very informative and interesting and I can see this product
appealing to a variety of people particularly those with an interest in carbon sequestration and building with products with less embodied energy.