WoodSolutions Demonstration Model

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.

At this station you can see a mock-up fire hydrant riser, demonstrating the basic connection detail between services and timber elements namely, screws. As you will see throughout this floor, all services can be roughed in and connect to the structure with the use of nothing more than screws and a battery powered driver. Before stepping through this doorway, have a look at how this has been cut out of the timber. For core walls, it is standard practice for the fabricator to cut most of the door penetration, leaving an un-cut area in each corner. This prevents unnecessary exposure to live edges until the door way is needed, at which point it can be cut out on site. Indeed, you can see this has occurred here, with smooth cuts to most of the door frame, and circular saw cuts at the corners.

At this station you can see a small display of screws typically used to connect massive timber structures together. When designing timber structures it is important to note that screws are sometimes able to perform the same function as an angle bracket, minimising the visual impact of the connection. Note that while the longest screw here is 300mm long, certain designs can call for screws that are much longer than this. While there are several suppliers of mass timber screws and bracketry, this structure demonstrates some of the range from Rothoblaas. The CLT in this structure has been sourced from XLam Australia. Take a minute to look at the central “spine wall”. Here you can see three layers of sawn timber, each of which has been oriented perpendicular to the last, glued, and pressed into a panel. It is important to note that CLT typically comprises an odd number of layers, so the two external layers span in the same direction. As you can see here, it is standard for external layers to run in the direction of the primary span or load. Here the primary load is vertical, and as such all panels have been designed so the external lamella run vertically. As with other engineered timber products, CLT reduces the impact of knots and other impurities, delivering a whole that is stronger and more robust than the sum of its parts. Before moving on to the next station, notice how loads are transferred from the landings to the core walls through the use of an angle plate. While a timber plate would also be effective in this circumstance, the combination of materials here gives an aesthetically appealing finish. Continue up the next half flight of stairs for the next station.

Welcome to the structural core of the building. This has been designed as a stair core, but could just as easily be a lift core or services rise as need be. The core of the project typically provides lateral stiffness, transferring shear and overturning loads to the ground. To accommodate these significant loads cores are typically built out of massive timber elements or heavily braced frames. At this level you can see the core structure comprises massive CLT panels. If you're unfamiliar with CLT make sure to have a listen to the “definitions” track in this audio guide. Here we have purposefully kept finishes to a minimum so you can see all of the connections between the elements. You can see how the CLT has been perfectly cut to size in a CNC machine, and how these significant structural elements are held together with advanced, high capacity screws and connectors. A unique feature of CLT construction, the CLT stair flights here re also completely pre-fabricated. These flights are produced as a thick panel, with treads then cut out with the CNC. Any off cuts of this process can then be recycled. You might wonder why the walls here are covered in plasterboard. In fact while fire risk is considered to be reduced within cores, compliance with the Deemed to Satisfy requirements in the NCC calls for a single layer of 13mm fire rated plasterboard to be applied to the inside walls of the massive timber core, and any soffit above the ground floor. For the next station walk up this first half flight of stairs.

This room has been finished to the standard one may expect in a completed project – the only un-finished work here is in the power point which has purposefully been left out to show the fire box behind it – a requirement when penetrating a fire rated element. In this room you can find some samples of the products you can see throughout the structure. Take this opportunity to touch and feel them – pick them up and see how heavy they are. With these simple elements you can build a large project, often only requiring battery powered hand tools during the structure stage. Timber construction sites typically require no hot works, wet trades, or other slow or high-risk trades. Timber construction has been proven to be faster, safer, and of a higher quality than experienced with traditional materials. Beyond this, depending on the design and other project parameters, timber projects are typically cost competitive with concrete and steel. You may also notice the sprinkler head above you – it is now a requirement under the NCC that all projects over 4 storeys are serviced by fire sprinklers, regardless of the building material used. The next station of this tour is in the stair well – we'll meet you there!

This last section of external area demonstrates a number of systems. At ground floor level you can observe another rainscreen façade system, this time in the form of a lightweight brick finish. As with all previous façade systems, this display features the rainscreen, ventilated cavity, vapour permeable membrane, fire protective plasterboard, and finally timber structure and non-combustible insulation. Of particular interest at this level is the façade finish, the Corium system available from PGH Bricks. This system allows for the prefabrication of brick façades on a panel housed in a safe, weather protected warehouse environment, which can then be delivered to site, installed, and joints “stitched” with remaining bricks. While there are several prefabricated brick façade systems available for use with timber, the specific product seen here is structurally robust, and is suitable for use up to 30 storeys. Immediately above this brick finish we can see a full fill solid timber cavity barrier. Note that this would normally be covered by the façade cladding, but we have chosen to reveal it here of display purposes only. This performs the same function as all other cavity barriers identified however as a “full fill” barrier this requires no heat to activate – it fully fills the cavity in its natural state. With this in mind, it is important to note that full fill cavity barriers in facades must be flashed, and any moisture within the cavity must be able to drain out over the barrier. Again, cavity barriers are not required in all designs, so make sure to talk to your fire engineer or building surveyor about what is and isn't required. Above this cavity barrier you can see the external side of a solid balustrade featuring the James Hardie ExoTec system. This will be discussed further once we reach that station upstairs. The next station on this audio guide is located within the finished room on the ground floor of the structure – walk around there when you're ready to continue the tour.    

The right-hand half of this main façade features the ExoTec rain screen system produced by James Hardie, supported by James Hardie's proprietary top hat sections. If you are starting this audio guide at this station, welcome, we recommend that you first watch the introductory video on the screen in the ground floor, and then commence your tour at station 1. Now, back to the guide: In this area you can see several now familiar products and systems. Again there is the rainscreen façade, the ventilated cavity, a vapour permeable membrane, two layers of fire and water rated plasterboard, ply bracing, and finally the stud frame structure complete with non-combustible insulation. As elsewhere you can see a tension connector on the corner of the panel, and a shear connector toward the middle of the panel. Again, the structure here is designed to transfer the loads of a seven-storey structure, and as such we can see triple LVL studs, and a high strength F17 bottom plate. A new feature of interest here is the tie down rod supplied by Simpson Strongtie. Typically used to resist the overturning forces applied by wind loads, this threaded rod is coupled at each floor, essentially delivering a single long steel cord to resist tension forces. This element is not required in all projects, by an engineer may elect to specify its use in particularly windy climates. For example, these rods are commonly seen in low to mid rise structures in tropical Queensland. Make sure to keep an eye out for this rod as we move up the structure.

Back to the main structure, the front façade features two main finishes. On the left hand side we have an Equitone finish, a pre-finished rain screen panel, which has been installed on the Nvelope system. Under this façade, you can see the system identified in stations 2 and 4 comprising a vapour permeable membrane, fire and water rated plasterboard, bracing as required, and finally the main structural element. Here, this loadbearing structure consist triple studs of LVL, with groups spaced at 450mm centres. With LVL studs typically achieving a compressive strength of between 47 and 51 MPa, it is clear that once they are nail laminated together in threes, each group becomes a mini-column. Keep in mind that this wall panel has been designed for the loads of a seven-storey structure, and as such this high loadbearing capability is necessary. Indeed, these high loads are the reason why the wall's top and bottom plates are a different colour to the studs. While rough sawn timber exhibits impressive structural capacity when loaded parallel to its length, when loaded in the tangential direction (as occurs with a top or bottom plate) lower strength graded timber is susceptible to crushing when heavily loaded. While this results in very little movement on a floor by floor basis, when occurring over several floors it can add up to shortening that must be considered during design. For this reason, we recommend the specification of higher strength timber in the top and bottom plates used in high load areas – something that can be seen here with the use of an F17 hardwood. The use of this higher strength material effectively mitigates the crushing, making for a straight forward design and construction process. Note that F17 LVL (as per the studs) would also perform this function adequately, however generic machine graded pine products would not be suitable for highly loaded areas.

Looking under the dis-assembleable section of the structure you can see a high performing wall type common in multi-residential developments. This partly finished wall is known as a discontinuous wall, and features two frames which have been installed approximately 20mm apart, making them completely independent of each other. This complete separation eliminates the direct transfer of vibration from one wall panel to the other, and when combined with the two layers of fire rated plaster board required to reach a 90/90/90 FRL, achieves an acoustic rating higher than all other cost competitive wall types for a similar depth. Indeed, when completed, the half-finished system here has been proven to provide an Rw+Ctr or airborne acoustic rating of 54. While the section of wall shown here isn't load bearing, it is important to note that discontinuous walls can be loadbearing, with floor cassettes bearing directly on to them. Where this is the case and 90mm timber studs are used, evidence suggests that timber party walls can perform more efficiently than is commonly seen in concrete post and slab designs, with wall thicknesses typically measuring up to 50mm thinner. While this may not seem like a lot a face value, a typical multi-residential project may feature hundreds of meters of party wall, and therefore this thinner panel may add tens of square meters in extra saleable area, and hundreds of thousands of dollars worth of extra revenue. Note that where there are discontinuous party walls located above each other on consecutive floors it is important that there is a cavity barrier installed between floors to mitigate the spread of fire between sole occupancy units. While this is difficult to show in a full-scale model, if you look closely you can see a strip of high-density non-combustible insulation which has been inserted between floor cassettes, blocking the vertical spread of fire.    

You may notice that this section looks a little different to the rest of the structure. There are no linings, services, or finishes in this section – only structure. The reason for this is that this section has been designed to be dis-assembled and re-assembled by project teams to better understand how panelised timber projects are put together. As you can see here, timber projects are typically made up of a variety of panels, whether they are mass timber panels as seen in the CLT on your left, stud frame panels as you can see in the LVL stud frames on your right, light weight cassette floors as you can see on the first floor, or massive timber floors as you can see on the second floor. Of particular interest here is the construction detail of the cassette floor, as this demonstrates two major forms of timber construction. As you can see, the cassette floor is sitting directly on top of the two stud frame walls, transferring load directly through all floor joist elements into the top plate of the walls. This is called platform construction, as the floor cassette for each floor makes a new platform on which load bearing walls can sit. In contrast to this on the left-hand side you can see the connection between the floor cassette and the continuous CLT core panel via a whaler plate. This connection has been achieved by pre-installing an LVL element on the side of the core, on to which the edge of the cassette can sit. This allows for simple installation, as the floor element can sit under gravity loads while it is being fixed off, with no temporary propping required during install. You might notice that this cassette is built out of a solid LVL rim board with light weight I-joists internally. While this configuration has been selected for display purposes, the composition of the cassette really comes down to the spans and loads of the structure. A great benefit of timber construction, all edge protection elements were pre-installed before lifting, eliminating all live edges on the project. This is a common experience on timber projects and is one of the reasons why timber construction is so safe. It's interesting to note the temporary props that have been installed to support the wall panels here. While the props aren't required to hold the structure up once fixed off, they have been left in this position to demonstrate their use during construction. Note the size of the props – the panels they support rarely total more than 2t in weight, avoiding the need to call on the big heavy props utilised in pre-cast concrete construction.

At this station you can see more of the massive timber core exposed. As you will see in more detail later in the tour, these panels are connected through the use of screws and brackets, and can be quickly and quietly installed on site. At the base of the core you can see a new plaster product used. A popular external lining in the United Kingdom, Siniat Weather Defence is an alternative the traditional water and fire rated plasterboards. It has been shown to perform as well as traditional fire rated plasterboard sheets under fire load and is manufactured complete with a water proof vapour permeable membrane integrally bonded into the face, reducing the number of work tasks on site. What's more, with the use of fire rated joining tape or sealant, the Weather Defence system can deliver an airtight lining to the façade of a structure.

At this station you can see two separate displays, one in the internal corner, and another on the external corner. The display in the internal corner demonstrates the use of external insulation behind a rainscreen cladding. Note that in this display, the rainscreen cladding has been demonstrated in clear Perspex so you can see connections and bracketry behind. In order of installation, this display demonstrates: fire protection, vapour permeable membrane, an intumescent cavity barrier, external insulation batts, an efficient rain screen façade bracketry system, the ventilated cavity, and finally the rain screen itself. Each of these items, and the system itself will now be discussed. This display spans across two different types of timber structure, and as such features slight differences in fire protection requirements. While the staggered stud wall to the left requires two layers of 13mm fire rated plasterboard to achieve an FRL of 90/90/90, the CLT element to the right only requires one layer of 16mm fire rated plasterboard to reach the same level. This difference in fire protection is made possible by the “massive” nature of the CLT element. While high temperatures and fire may be able to impact a stud from three sides, massive timber elements are by definition, much larger and as such are able to withstand fire loads on their own for a longer period. While the vapour permeable membrane utilised in this display is a different product to the silver TBA Firefly product shown on the left, it ultimately performs the same function. This product – Wraptite Self Adhesive distributed by Proctor Group Australia – features a self-adhesive on one side, making an air tight envelope more easily achievable. You may notice that there is another red element installed above the insulation batt on the left-hand side of the display. This product is an intumescent cavity barrier. Backed with a densely packed block of non-combustible insulation, this intumescent strip is designed to expand in the event of a fire, filling any cavity between the insulation and cladding, and effectively preventing any fire spread under the cladding. Note that cavity barriers may or may not be required depending on your design and have been shown in this structure purely for display purposes. Next, you may notice the use of insulation within the façade system. In compliance with the requirement for a fire-safe façade, the insulation used in this display is non-combustible. While external insulation may or may not be required depending on your design (and the climactic conditions of the area in which your project is situated), it is important to understand it's use and ensure it is specified where needed. External insulation is used in heating climates, where it is best practice to keep the structure warmer than external conditions, artificially elevating the dew point. This artificial elevation means that water vapour will not condense in within the structural element, instead permeating through it, and the vapour permeable membrane before cooling and forming liquid water. The insulation on display here also features a waterproof membrane to further limit the ingress of water and can be sourced from Proctor Group Australia. The rain screen façade can be supported by a range of different brackets and frames. Here we have elected to utilise the NVelope rain screen support system, as this allows for external insulation batts to butt up to each other with minimal loss of insulated area. While an alternative system utilising top hats may achieve the same function in supporting the façade, this would leave large gaps between the insulation batts where the top hats sit resulting in an imperfect system for thermal insulation. Note that this bracket system also provides a slight gap between external insulation and cladding, allowing for a ventilated system. Finally, the rain screen. While this display utilises Perspex, there are a wide variety of different non-combustible rain screen products available on the market today. This demonstration model shows several different rainscreen systems, although this is just a small sample of what is available on the market today. The external corner demonstrates a vertical connection between two CLT panels. CLT panels can be produced in lengths of up to 16 metres, making it very easy to produce core panels that are two, three, or even four storeys high if you can transport them. In this structure we have utilised double height CLT panels to support installation efficiency. With tall panels come long joints, and in this structure all joints have been taped with a high-adherence non-permeable tape. This tape limits air leakage into and out of the structure, and is instrumental in delivering an air tight structure where this is sought. Note that this external corner also shows a typical angle connection between a massive timber panel and concrete slab. While the specific connector used in this location may vary depending on the design of the building, we have shown a titan angle bracket produced by Rothoblaas.    

At this station you can see the outside face of the staggered stud wall. While you can see several elements discussed in station 1, here you can also note the face connector plates typically used on walls located at the slab edge. The longer steel plate on the left-hand side is designed to function in tension, and as such has been installed near the corner of the wall panel. In contrast to this, the shorter, wider steel plate on the right-hand side has been designed to function in shear and is therefore located closer to the centre of the panel. There are typically several of these plates used on every panel, with tension connectors at each corner and shear plates spaced at specified centres. Note that each of these plates has been bolted to the grey concrete slab with a concrete anchor and has been connected to the timber element with nails. As identified earlier, this panel also features a bracing lining of OSB to laterally restrain the studs, and the fire protective linings required to achieve the required FRL. This external face has also been treated as an external wall, and as such features a vapour permeable membrane. Note that if built, this would still require protection from rain and weather as provided by any of the rainscreen systems demonstrated on this structure.

On the outside of the non-loadbearing nib wall you can see a small display of James Hardie's ComTex façade system, which has been designed to deliver a render finish to light weight structures. Note that the yellow façade panel here performs as a pre-primed and textured base, ready for the addition of a textured acrylic coat. When selecting a colour finish to fibre cement-based façade panels it is important to consider the light reflectance value of the colour and exposure level of the panel, as darker finishes will attract more heat in high exposure locations and may risk damaging the facade as it expands. This product requires finishing with a colour attracting a light reflectance value of at least 40, which roughly correlates to light pastel or cream shades.    A common theme amongst all the façade systems shown on this structure, the ComTex system effectively acts as a pressure-equalised rainscreen, featuring a ventilated cavity between the visual façade and the vapour permeable membrane behind. This gap allows for the natural egress of any moisture that enters the system, minimising the risk of water damage. The vapour permeable membrane utilised behind this rainscreen has been supplied by TBA Firefly, and is classed as both vapour permeable and non-combustible. It is important to utilise a vapour permeable membrane in timber facades, as this allows moisture to permeate out of the timber system while preventing moisture from entering. While there are a number of membranes marketed as “breather membranes” it is important that any membrane used in this function is highly permeable, and supports a rate of vapour transmission of at least 4 µg/N.s. (4 micrograms per newton second). Behind this vapour permeable membrane, you can see two layers of 13mm fire wet stop plasterboard supplied by USG Boral. Even though this wall is non-loadbearing, it is a requirement for all combustible elements utilised within a façade to be fire protected to a specified FRL.

At this station you can see two different wall types on what would be the ground floor of the seven-storey timber structure, as well as the floor system of the floor above. The wall type to the left is known as a “staggered stud” wall, referring to the staggered position of the studs on the larger bottom and top plates. This wall type is effective in reducing the transfer of vibrations from one side to the other, and as such is suitable for use where high acoustic standards are called for. Note that this wall type features double studs of Laminated Veneer Lumber or LVL at relatively close centres – this high number of studs has been specified to transfer the significant loads experienced on the lowest floor of a seven-storey structure. Note that this staggered stud configuration doesn't allow for the use of noggins, and as such all studs are laterally restrained by bracing sheets on each side of the panel. This wall panel has been secured to the slab with the use of a proprietary angle bracket from connector producer Rothoblaas. As you can see, this bracket features large holes on one side to allow for concrete anchors, and smaller holes on the other to allow for nails or screws connecting to the wall panel. While this bracket is located away from the edge of the panel and is therefore intended for the transfer of shear loads, there are a variety of other bracket types throughout this structure. Finally, you will notice that the wall is lined with two layers of 13mm fire rated plaster board. This lining has been tested and proven to achieve a Fire Resistance Level of 90/90/90, an FRL commonly required for façade or party walls. In contrast to this robust structural wall, the nib wall to your right-hand side demonstrates the system you may find on a non-loadbearing façade wall (set back from the property boundary). While the loadbearing staggered stud wall requires double LVL studs at close centres, this non-loadbearing element is constructed of single machine graded pine studs at larger centres. Even though this element is non-loadbearing, note that as it is a façade element it must still achieve an FRL of 90/90/90 (assuming it is set back from the property boundary), explaining the two layers of 13mm.

The WoodSolutions Mid-rise Demonstration Model is a mock-up of a 7 storey apartment building to illustrate details of a mid-rise project. In this audio guide there are 23 different audio stations with examples of some of the ways you can successfully design and build a mid-rise building with engineered timber products. In three levels, you'll see examples of the structural, fire and acoustic systems commonly found in mid-rise timber buildings.  The apartment structure is seven storeys of timber construction over a ground floor concrete podium and basement car park. The elements of the floor plan illustrated in the model include a typical apartment bedroom, bathroom, living space and stair shaft – plus an added balcony. The three levels constructed in the demonstration model reflect the differences in seven storeys of timber system construction. The top level of the model represents the top 3 storeys of the apartment, with only single stud walls required. The centre level represents the central two story, where you'll notice double stud walls. On the bottom floor there are triple stud walls to carry the higher load from above.