Share WoodSolutions Demonstration Model
Share to email
Share to Facebook
Share to X
By Adam Jones
The podcast currently has 25 episodes available.
In this recording we provide a brief introduction to the main timber products shown in this structure. Throughout this guided tour we refer to several Engineered Wood Product by their popular abbreviated names. In this section of the audio guide we provide a definition of these products, detailing how they are produced and noting where they are typically most effectively utilised. Note that we will also define a few commonly used terms to avoid future confusion. These products and terms will be discussed in alphabetical order, so you can easily fast forward or re-listen to segments if need be.
At this station you can see two ways to achieve fall in a roofing element. While traditional on-site roofing is still common, it is also possible to build roof cassettes in a safe and clean off-site facility, significantly reducing the amount of work to be completed on site. Prefabricated roof cassettes can take many forms. The first example here is demonstrated at floor level, and shows a flat cassette which features battens, external insulation, deep profile roof cladding, and a fall restraint anchor. This system is simple to fabricate and transport, as it essentially sits flat on the factory floor (or the bed of a truck). Fall is them implied to the roofing element through the varying height of loadbearing elements, with the external elements fabricated to be shorter than the internal elements. Where the element is prefabricated complete with cladding, some cladding would typically be left off on either edge of the cassette so it may be “stitched” together and made watertight once installed.
The second example shown here can be seen above you at roof height, and shows a roof cassette with a fall built in through the use of a graded batten system. Similarly to the first example, this system features battens, and insulation blanket, and roof sheeting. While this system may be a little less efficient to fabricate and transport, it allows for higher roof gradients, and as such may be required in areas of increased rainfall or snow. This larger cassette option also demonstrates how the structure of the box gutter can be built into the prefabricated element, again minimising work on site.
While both systems are examples of advanced prefabrication, it is possible to reduce the amount of prefabrication undertaken in either. For example, you may elect to only life the cassette with battens, installing the roof sheeting as a separate work task.
This brings us to the end of this audio tour of the WoodSolutions Mid-rise Demonstration Model. Thank you for your attention, if you have any questions you may like to review the library of WoodSolutions technical design guides, utilise our “Ask an Expert” service, or contact the mid-rise team directly – all are freely available and can be accessed through the WoodSolutions website at www.woodsolutions.com.au.
At this floor you have an opportunity to walk on a full size CLT panel, comparing its under-foot feel to the lightweight systems utilised throughout the structure. Note that both lightweight and massive systems at this floor are completely bare, with no fire rating underneath, and no acoustic build up on top. This “raw” state allows for some comparison in the feel of the systems, however keep in mind that once completed this difference may be reduced.
While walking on the CLT floor panel, consider a few of the details and items on display in this space. First, you may notice that the top of the boards in the top lamella of the CLT panel are directed across this space. As discussed earlier, this is because the outside lamella should always be placed in the axis of primary loading, or in the direction of the longest span. In addition to this, you can see that the panel has been secured to the loadbearing walls below with screws, and that synthetic lifting slings have been pre-installed for easier lifting on site. The purple colour of these slings identifies their lifting capacity of 1t each – perfect for use with timber panels that typically weigh in under 2t and require two slings for stability while lifting.
As displayed on the first level, this level also features a simple edge protection solution supplied by Rapid EPS. This system offers either top or side mounted edge protection, allowing for flexibility in the installation of internal wall panels and acoustic floor topping systems. When selecting edge protection for use on a timber project it is important to ensure that all fixings are installed as specified, as the strength of the barrier is only as strong as it’s connection to the structure.
When you’re ready, walk over to the final room of this tour where we will discuss roofing options in your timber project.
Welcome to the top floor of the mid-rise demonstration model, representing what could potentially be the top three storeys of your building. At this floor the structure is subject to significantly reduced loads, and therefore requires a reduced structure comprising machine graded pine stud frame. This is well demonstrated at the entrance to the floor, where a staggered stud wall is fully exposed. Contrast this to the staggered stud wall on the ground floor, which featured double LVL studs staggered at 150mm centres – a significant difference to the MGP10 studs before you.
Indeed, you may notice that the structure of the stair core also transitions from high capacity massive timber to lightweight stud framing. Again, while it isn’t common for the structural system utilised in the core to change, this heavily braced lightweight system is a valid and effective approach and therefore is worthy of display.
This station is located in the stair core, at the mid-level landing between the first and second floors. At this point you can see the transition of the core structure from CLT to another massive timber material – LVL. While it isn’t typical to see two different massive timber cores stacked on top of each other like this, this has been done here simply to demonstrate that both materials are suitable for use in the core. In contrast to CLT, which is produced on a panel by panel basis, LVL is produced on a rolling press 1.2m wide, meaning that the maximum width of an LVL panel is 1.2m, however the length can be as long as you can transport. Note that LVL is strongest parallel to the grain, and as such depending on the design of the core it may be best aligned vertically – an example of this can be seen at Station 21.
At this horizontal joint between the two massive timber elements you may notice a thin yellow rubber strip. A best practice solution between elements exposed to vibration or impact, these strips are designed to absorb energy, limiting the transfer of vibration between panels. Areas where these strips are required include lift cores, stair cores, or other high impact zones. A great benefit of panelised construction over monolithic structures, the accurate use of these strips can minimise the transfer of structure borne sound, improving internal environmental quality throughout a structure.
Also visible at this station are a number of timber to timber plate connectors. These plates are designed to transfer tensile loads which may be experienced in a core element under wind loads. Note that while these plates have been nail filled, they can also be fixed off using screws.
When you’re ready, keep walking up the stairs to the next station.
Immediately adjacent to the glulam post and beam display you can see a display of one of the several potential balcony systems. While we typically recommend this use of “bolt on” balconies where the structure of the balcony is completely separate to that of the main building, it is common for balconies to exist over a habitable space. This balcony seeks to demonstrate this scenario and assumes that the balcony surface cannot be set down from the other areas as this is commonly the case with massive timber construction. In this section we will discuss each of the elements of this balcony in detail.
You may notice that the threshold of the balcony is raised. This is required where the balcony cannot be set down as it allows for effective separation of the indoor and outdoor environments and mitigates the risk of flooding through this interface. To achieve this height separation, we have constructed a 90mm high hob out of two treated pine studs. With this installed we have utilised Multipanel, a proprietary waterproofing system which is highly suitable to timber projects and is currently being specified throughout the industry. This light weight polyurethane board is produced in a number of sizes and can be machined to include a fall as per your design, avoiding the need for graded battens or screeds. With each board easily cut to size they are then glued together with a polyurethane compound, providing a completely water tight membrane. Here you can see that Multipanel completely lines the hob and floor of the balcony, with treated pine battens and a hardwood deck providing a permeable walking surface. The Multipanel waterproof membrane then falls toward the waste point, located in the front left-hand corner of the balcony. Note also the overflow chute in this location, allow the water to flow out of the balcony if this waste were to become clogged.
Balustrades vary substantially in material and design, however in this display we have shown how you can build a solid balustrade as is common in in-set balconies. This element is fully exposed to the weather, and as such requires a similar treatment to the façades seen at ground floor. Here you can see that the balustrade has been constructed out of H3 treated pine, a treatment level suitable for use outside and above ground. Even though this element isn’t loadbearing, it is located on the façade of the project, and as such the timber must be fire protected to a specified FRL. For the purpose of this display we have assumed that the balcony is located on the boundary of the property, and as such the element attracts an FRL of 90/90/90. On this fire rated lining you can see a vapour permeable membrane, a ventilated cavity, and finally the façade finish. Note the flashing at the interface between this balustrade system and the Multipanel, ensuring that any moisture within the system simply runs onto the waterproofed balcony system.
Other systems displayed in this balcony area include fire protected structural timber both to your left and on the ceiling, and the continuation of the tie down rod first observed downstairs.
The next station on this audio guide is located in the stair core on the mid-level landing. Feel free to take some time to review the details on this level and move on when you’re ready.
This room is one of the most detailed in the structure, with different fire, acoustic, structural, and waterproofing systems shown in one space. This audio guide will discuss each element in a logical sequence, starting with the floor, then the ceiling, then focusing on some of the more interesting features at eye height.
This room demonstrates how simply a bathroom set down can be achieved in lightweight timber construction, with all designed set-downs fabricated into the floor cassettes and delivered to site pre-made. Here we show a traditional cement sand screed system with a liquid waterproofing membrane, and two options for service risers. The white riser to your right-hand side is constructed out of Promat’s L-500 board - a self-supporting fire rated board which requires no framing support – and features a few typical service penetrations treated to test standards with Promat fire collars.
On the left-hand side of the room you can see an alternative to this shaft which has been laminated out of three layers of fire rated plasterboard, a solution detailed in most published plaster guides.
When you’re ready, pop over to the adjacent room for the next station on this tour.
A common question amongst building professionals, it is important to understand how penetrations through fire walls should be treated for a variety of different services. On the central wall here we have displayed a multi-service penetration through a fire protected loadbearing wall. While there are several fire penetration solutions available on the market today, this solution has been supplied and tested by TBA Firefly. To ensure compliance of this penetration it was important to first ensure that all timber structure on both faces, and inside the penetration was lined with the sufficient fire protective lining to achieve the desired FRL. One lined the void could be filled with 100mm of high-density non-combustible insulation known as Intubatt, with all service penetrations running through this. Note the different fire stopping requirements of different services. For example, a cable tray requires different treatment to a pex pipe, which in turn requires a different level of treatment to a large diameter PVC pipe.
While this solution is indeed an effective one for zones featuring multiple penetrations, individual penetrations can be treated separately where required. An example of this has been provided at our next audio guide station, in the small room to your right.
Catch you there.
Moving into the first floor you can see that the linings in this area have been reduced, with much of the structure on display. This first room displays several interesting structural and services systems. First, you may notice the open frame wall in front of you. Featuring a larger window opening, this wall would typically require heavy ply bracing to provide resistance to lateral forces. Instead, the wall features two braced frame elements: a wall truss brace manufactured by Multinail and a short wall brace manufactured by Timbertruss for MiTek. The designers of these elements, MiTek, Multinail, and Pryda each design and manufacture the light gauge steel connectors you can see here, and in the floor joists throughout the project, while Timbertruss is the Southern Hemisphere’s largest fabricator, producing kilometres of floor joists and wall frames in their highly automated Geelong factory.
If you look on the floor, you will notice a strip of bracing reinforcement that has been run parallel to this wall. This strip is known as a drag strip, and is a tool that can be used by engineers to hold all floor cassettes together, and ensure they work as one. Note that type and number of nails used to secure this strip to the floor membrane will vary by design, as will the type and layout of drag strip across lightweight floors.
Moving from the floor to the ceiling space you can see that here there are no ceiling linings, revealing the floor structure in its entirety. The floor joists utilised here have been designed by MiTek, Multinail, and Pryda, each with their unique qualities. In looking at these it is important to note their customisability. No matter its size, any project utilising a lightweight floor system must be designed and optimised by the experienced design team employed by the fabricator. While it is possible to reticulate services through the open web of the joists as you can see them, it is also possible to design blocked out void sections to support the reticulation of larger ducts and pipes across the floor joists. With most services reticulated through this cavity, this lightweight floor system can deliver an efficient floor depth for a given span. Indeed the fabrication of these floors is as considered as their design. The floor area is broken into manageable cassettes of up to 3m by 12m, and these are fabricated in a controlled factory environment before being delivered to site. Once on site these cassettes can be installed at an impressive rate. While dependent on-site conditions and the actual design of the project, it is not uncommon to hear of whole floors being installed in a single day.
Finally, you may also notice a 130mm thick piece of timber running perpendicular to the floor joists in this area. This is known as a strongback and is used firstly to bind the floor joists together, ensuring they work integrally. The second use of this strongback is to add lateral stiffness to the floor element, reinforcing it for when it is lifted into position on site.
The next station in this audio guide will discuss penetrations for fire rated walls, and how this can be easily achieved as part of a Deemed to Satisfy solution.
The podcast currently has 25 episodes available.