CROSS LAMINATED TIMBER TECHNICAL BROCHURE

CROSS LAMINATED TIMBER TECHNICAL BROCHURE

V 2 . 4 JANUARY 2021

Red Stag Wood Solutions (RSWS) is the leading independent manufacturer of Cross Laminated Timber (CLT), timber frames, trusses and prefabricated building solutions for residential and commercial construction in New Zealand.

FRAME & TRUSS

CLT WALLS

SAVING THE PLANET

CLT STAIRS

CLT BEAMSCLT ROOF & FLOORS GLUE LAMINATED TIMBER

FLOOR CASSETTES

PANELISATION

CROSS LAMINATED TIMBER

Cross Laminated TimberOverview & Introduction

SECTION 1

Factory OverviewRed Stag Wood Solutions Limited (RSWS) exists to help transform timber construction through technology, to further support

the building industry, which is vital to the environment and the social fabric of our communities. RSWS is focusing on developing new products and solutions to drive productivity, while drastically reducing the carbon footprint of construction, in parallel with providing relief for housing shortages and affordability. Figure 1 shows the panoramic view of Red Stag’s primary site in Rotorua.

RSWS is the legal entity within the Red Stag Group focusing on structural Engineered Wood Products (EWP), including but not limited to Cross Laminated Timber (CLT), Glue Laminated Timber (GLT), Frame and Truss (F&T), advanced stick panelisation and cassette systems. RSWS installed its first CLT vacuum press in 2018 to support the establishment of New Zealand’s only scale structural CLT plant. RSWS is now in the final phases of constructing the first phase of New Zealand’s largest and most advanced CLT plant, with the facility scheduled to commence commissioning and operation by the end of 2020. The scale facility has the ability to manufacture billets nominally up to 16.5 x 4.5 x 0.4 m (Length x Width x Depth); however, can theoretically go as large as 16.8 x 4.9 x 0.42 m (press dimensions are 17.0 x 5.0 x 0.4 m). Figure 2 shows the panoramic view of the existing Red Stag Timber Limited (RST) remanufacturing line that is scheduled to support with higher appearance grade feedstock for CLT as required.

CLT is fundamentally changing the way buildings are designed, manufactured, and constructed. RSWS’s investment and innovation will help CLT become the backbone for future generations of high-performance, low-carbon construction, in traditional, mid and high rise buildings.

New Zealand and the Pacific regions are in the early stages of a CLT construction boom, driven by increasing demand and expanded building code acceptance of mass timber structures (Figure 3). CLT allows developers, designers, and builders to move beyond the traditional construction trade-offs to create buildings that are sophisticated and efficient, rapidly assembled, structurally sound, affordable and aesthetically stunning. As access to high-quality CLT continues to expand in New Zealand, RSWS believes it will become the material of choice across a broad range of market sectors, building types, and geographies.

Figure 1: Red Stag’s primary site in Rotorua.

Figure 2: RST remanufacturing line.

Figure 3: Mass timber construction.

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RSWS’s CLT Research & TestingRSWS’s goal is to develop the most advanced

mass timber building systems in New Zealand, making them more widely available, more efficiently produced, compliant to New Zealand standards (including treatment), more cost-effective and of higher quality than ever before (Figure 4).

CLT is much more than simply a structural building material. It is an opportunity to evolve building design and construction, making it easier to create buildings that are elegantly designed, efficiently built, and environmentally responsible, all while providing unparalleled long-term investment returns. To achieve these lofty goals, RSWS take an integrated approach and applies technology at every step of the process. RSWS is establishing end-to-end mass timber expertise and making unprecedented investment in CLT Research & Development (R&D), testing, manufacturing, design, engineering, and construction. With this level of control and innovation, RSWS can provide its partners with the most advanced building systems available.

RSWS CLT is a building material that offers a unique combination of efficiency, strength, safety, aesthetics, and environmental benefits to deliver value across the entire construction ecosystem.

For DevelopersThe efficiency and accuracy of Computer Numerical Control (CNC) machined EWP and designs significantly reduces construction times (reduced holding costs and labour hours), reduces noise and associated consenting challenges, reduces site waste, improves site health and safety and generates higher sales and retail returns generated by the proven benefits that timber provides to occupants (physiological and psychological).

For Owner/OperatorsThe superior aesthetics and operational efficiencies of mass timber buildings present unique opportunities for design differentiation, high occupancy demand, and long-term asset value growth. The option for exposed CLT generates a robust substrate for reduced maintenance. Timber buildings have proven to generate a higher lease rate through the physiological and psychological benefits that exposed timber provides occupants.

For Architects & EngineersCLT’s inherent structural, aesthetic, and biophilic characteristics offer unique design possibilities that blend form, function, user experience, and sustainability. Combining CLT and EWP with large scale five-axis CNC’ing allows for the most complex and advanced designs and associated Building Information Modelling (BIM) to be seamlessly converted from concepts on paper/screen into reality.

For BuildersAs a prefabricated material, CLT moves labour upstream and offsite, reduces site waste and site logistics, significantly speeds up site build times, reduces site noise and debris, improves safety (reduced labour units, less time at height, less processing on-site), reduces the impact of weather, and generally mitigates many of the other risks associated with traditional construction on site.

For Tenants & CitizensMass timber buildings are at the forefront of healthy and dynamic communities, providing physiological and psychological benefits to the people who live and work in them, and reducing the environmental impact of construction. The health benefits include, but are not limited to: reduced blood pressure, reduced stress levels, improved attention and focus, greater creativity, faster recovery, and reduced pain perception1.

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Environmental & Sustainability Impact of CLTConstruction generates 11 percent of the world’s CO2

emissions, from embodied carbon emissions, or ‘upfront’ carbon that is associated with materials and construction processes throughout the whole building lifecycle2. Two of the most conventional building materials, concrete and steel, are among the most carbon-intensive to produce, therefore contribute to the majority of the construction CO2 emissions. Switching to lower carbon footprint alternatives such as CLT can significantly reduce a building’s negative environmental impact. In contrast to concrete and steel, CLT is a renewable material that sequesters carbon during its life cycle. CLT is a lighter, stronger, more sustainable alternative to concrete and steel structures. The environmental and sustainability advantages of building with CLT as compared with concrete and steel are derived from the inherent qualities of wood as a carbon-capturing material, that also requires lower transportation costs (lighter and less loads as compared to traditional materials), and expedites construction time to further reduce the net CO2 for associated builds (Figure 5).

Embodied Carbon Concrete

+2,000Tonnes

CLT+976Tonnes

Net Carbon Footprint+ 2000TonnesCO2

- 2600TonnesCO2

Cross Laminated TimberCLT is a high-performance mass wood product that comprises graded boards, which are glued together in a cross-layered manner, with

each layer orientated 90 degrees to each other. RSWS CLT is manufactured from New Zealand renewable FSC certified forestry, typically in three to eleven layers, with a total thickness ranging from approximately 51 mm to 420 mm depending on the structural requirements (refer to Figures 6 - 8).

Figure 6: Sawn log.

Figure 8: Final CLT product. Grain Direction in Transverse LaminationGrain Direction in Longitudinal Lamination

CLT Thickness3 to 11 layersMinimum 51 mmMaximum 420 mm

CLT Span (Maxim

um 16.5 m)Panel Orientation

CharacteristicsCLT panels gain the majority of their stiffness

from the outer structural layers (defined as longitudinal laminates regardless of length). Transverse laminates help to bind the structural layers but do not require the same structural properties. RSWS manufactures panels using specified layer properties, defining the Modulus of Elasticity (MoE) to align with the performance criteria of the panel (Table 1). RSWS panels are glued together using Polyurethane Reactive (PUR) adhesive.

The benefits of CLT include design flexibility, extremely fast installation, reduced mass loading and foundation requirements, exceptionally good structural properties, outstanding seismic performance, and a very good fire rating. CLT is a highly cost-effective material compared to concrete and steel and a significant sequester of carbon, making it an environmentally friendly solution to mid-rise construction.

Figure 5: CLT versus Concrete: A Sustainability Comparison.

Figure 7: Arranging boards.

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CLT Performance Quality CheckRSWS manufactured CLT panels and associated feedstock have been tested by professional third parties to ensure the durability,

mechanical strength and fire resistance. As shown in Figures 9 - 11, a series of large-scale experimental tests have been conducted on RSWS CLT products to verify the quality performance of the products.

Destructive large-scale four-point bending tests conducted by Scion confirmed that the manufactured CLT panels have a sufficient level of stiffness and strength to carry applied structural loads (Figures 9a - 9d). Testing on short, intermediate and long-span CLT panels showed their great structural performance under large pure shear forces, pure bending moments and the combination of the two. The results confirmed that the CLT panels outperformed the theoretical design calculations and associated numerical modelling.

Table 1: Material Strength Properties *Structural Properties Longitudinal Laminates Transverse Laminates

Modulus of Elasticity (MoE) 8 GPa 10 GPa 12 GPa 6 GPa

Bending Strength 14 MPa 20 MPa 28 MPa 10 MPa

Compression Parallel to Grain 18 MPa 20 MPa 25 MPa 15 MPa

Compression Perpendicular to Grain 8.9 MPa 8.9 MPa 8.9 MPa 8.9 MPa

Tension Strength 6 MPa 8.0 MPa 14 MPa 4.0 MPa

Nominal Shear 3.8 MPa 3.8 MPa 3.8 MPa 3.8 MPa

* Refer to NZS 3603: 1993

dcb

a Figure 9: Large scale mechanical testing conducted by Scion.

Figure 10: Delamination test specimens.

The glue bond quality and durability of the CLT layers have been assessed by delamination testing. The reported delamination test results by a third-party specialist company showed an average delamination percentage under the standard allowable limitation, confirming the glue line bonds are sufficiently durable (Figure 10). In addition to the delamination testing, the large-scale bending experimental tests verified that there were no adverse issues associated with glue line performance. No glue line failure or board separation was observed during all large-scale deflection testing.

Test specimen before delamination test Test specimen after delamination test

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The Fire Code is formulated to permit time for occupants to safely leave a burning building before structural collapse or succumbing to heat or smoke inhalation. The code stipulated safe evacuation period of up to 60 minutes in New Zealand will cover the vast majority of building types and uses. Large-scale CLT panel fire testing was conducted by RSWS to determine the overall fire resistance and fire performance of the panels under structural loads (Figure 11). The CLT test specimen was installed at the top of the furnace to investigate a number of parameters such as the structural performance of CLT panels during the fire test, temperature profile and deflection. The third-party fire test report confirmed no structural, integrity or instability failure after more than 60 minutes. Figure 11: A general view of the large-scale fire test set-up

and associated test specimen after the fire test on RSWS CLT.

c

b

a

d

6

In addition to the experimental test results and positive feedback of third-party specialists, RSWS tested and investigated its products numerically. A typical 3D sketch and associated finite element mesh model for the CLT panels are shown in Figure 12. RSWS’s technical team can provide a comprehensive technical statement, including CLT design calculations, experimental test reports and numerical analysis for each project separately if required by the client3.

Figure 12: Typical boundary conditions and Finite Element (FE) mesh used in this numerical model by ABAQUS software.

(a) FE model boundary conditions (Load and support) (b) FE mesh (c & d) CLT panel numerical model to find out the deflection and stresses under various loading conditions.

Cross Laminated TimberApplications & ProductSpecifications

SECTION 2

CLT for Floor and Roof ApplicationsThe Gamma method presented in the FP Innovationa CLT design guide has been used to design CLT panels for roof or floor

applications. This design method takes into account an additional deflection to the initial vertical deflection due to roiling shear deformation in the transverse laminate(s), which is a key issue that may control the design and performance of the CLT roof and floor system(s). Dissimilar to the long spans in CLT roof or floor panels, the shorter spans have a higher proportion of rolling shear deformation (Figure 13).

Vibration : Vibration (e.g. harmonics created by movement across the floor) is another important factor that needs to be taken into account during the design of CLT floors. The laboratory shows that the vibrational behaviour of CLT floors is different from lightweight joist floors. The vibrational impact on the span of CLT floors is calculated based on the FP Innovation design method. This method has been verified experimentally by a series of laboratory tests performed by FP Innovations.

CLT Roof Design The midspan deflection calculation result under k2(G+GSDL+0.4Q) should be lower than the Span/300 for simply supported and cantilevered roofs. G is the gravitational weight of the CLT panel (refer to Table 1).GSDL is the added structural design load on the CLT roof, which is 0.1 kPa.Q is the imposed load, which is 0.25 kPa.K2* is the long term creep factor, which is 2.0 for the serviceability limit state deflection check of simply supported and cantilevered floors.*Assumed that the CLT roof remains dry during its service life-time.

CLT Floor DesignThe midspan deflection calculation result under k2(G+GSDL+0.4Q) should be lower than the Span/300 for simply supported and cantilevered roofs.G is the self-weight of the CLT panel (refer to Table 1).GSDL is the added super-imposed load (the CLT floor table is arranged for 0.5 kPa,1.0 kPa and 1.5 kPa supper-imposed loads).Q is the imposed load (the CLT floor table is arranged for 2.0 kPa, 3.0 kPa and 5.0 kPa).K2* is the long term creep factor, which is 2.0 for the serviceability limit state deflection check of simply supported and cantilevered floors.*Assumed the CLT roof remains dry during service lifetime.

CLT Floor

CLT Roof

Figure 13: Standard representation of a simple CLT roof and floor system.

aFP Innovations is a private Canadian organisation that specialises in the creation of solutions in support of the Canadian forestry sector.

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RST’s mill focuses on structural gauges, with the most common being 90x45. To produce 90x45 gauged timber, RST cuts 100x50 Rough Sawn (RS), which is then further processed to create the final 90x45 gauging.

RSWS’s CLT plant will have three primaryb feedstock thicknesses: 45 mm, 50 mm RS, and 25 mm RS. Subject to the CLT recipe requirements, wherever practically possible, 45 mm thick feedstock will be used to make the processed CLT as economical as possible (reduced price point).

RSWS is currently refining it’s remanufacturing line to target generating 42 mm thick lamella from 45 mm feedstock (the maximum range will be 41 to 42 mm). RSWS is also integrating a rip process for feedstock, therefore the maximum size of ripped and gauged 45 mm lamella is 17 mm (the maximum range will be 15 to 17 mm) (Table 3).

The secondary feedstock option is 50 mm RS. To create lamella gauges of 44 – 45 mm thick, 50 mm feedstock must be used (maximum gauge is 45 mm). The maximum theoretical size of ripped and gauged 50 mm lamellas is 19 mm (the maximum range will be 17 to 19 mm). The third feedstock option is 25 mm. To create lamella gauges 20 mm thick, 25 mm feedstock must be used (maximum gauge is 21 mm). It must be noted, that the price calculation for the input raw materials into each EWP are based on the feedstock gauge, therefore the price will not decrease if the Client selects a narrow gauge (i.e. 43 mm thick lamellas will be the same price as 35 mm lamellas). As RST is a structural mill, predominantly servicing the New Zealand market, the largest majority of the feedstock will have an average MoE of 8 GPa. As such, the longitudinal layers of the CLT will generally be specified as 8 GPa, with the majority of the transverse layers being specified up to 6 GPa. RST will have 10 GPa and potentially higher feedstock available; however, will focus its designs around 8 GPa and 6 GPa feedstock to make CLT as economic as practically possible relative to the properties of New Zealand Radiata Pine in the Central North Island.

RST is providing RSWS with pre-treatedc feed stock for its EWP. To ensure the quality of the glue bond on the processed EWP,

RSWS needs to minimise the time between final planing and glue application/pressing. As such, RSWS must plane the pre-treated feedstock before the gluing process. To maximise the retained treatment, RSWS targets to plane as little timber as possible from lamellas, and as such recommends lamella thicknesses of 40 mm and above for the 45 – 50 mm thick feedstock and no less than 20 mm for 25 mm thick feedstock.

RSWS CLT Configuration OptionsRSWS has the ability to create a range of

CLT configurations or recipes, including 3, 5, 7, 9 and 11-layer panels in architectural and industrial grades. A simplified range of CLT panel configurations for floor and roof applications are summarised in Tables 2 - 6. Additional CLT configurations beyond those presented in the tables below are available based on the client’s requirements; however, feedstock references will determine the availability, viability and cost position of alternate configurations.

A significant benefit of CLT and timber as a whole, is its ability to lock up carbon. For every one cubic meter (1m3) of timber utilised in a building, it removes 0.8 tonnes of CO2

5. The CO2 is absorbed by the timber and the carbon is stored/sequestered. Therefore, for every 1m3 of CLT, it will sequester 240 kg to 250 kg of locked-in carbon 5, 6,7 (Figure 14). To highlight this exceptional environment advantage, RSWS calculated the CO2 benefits for CLT products individually and has summarised in the CLT panel specification tables below. The maximum span for cantilevered, simply supported and continuous CLT floors and roofs based on the FP Innovation CLT design guide and the New Zealand design action standard (AS/NZS 1170) are summarised in Tables 7 - 10.

1m3

1m3

Producing 1m3 of concrete wall emits 110 kg of CO2

1m3 of timber stores 250 kg of carbon

Lamella Specifications

Figure 14: CLT versus an equivalent concrete block.

b RST produces the majority of its timber in gauges ranging from 70x45 to 300x50 mm.c RSWS will have the option for non-treated EWP if the client has a specific requirement; however, will strongly encourage treating all EWP that it produces.

019

10

Table 4: 3 Layer CLT Panel Specifications

Panel Title CLT 3/60 CLT 3/82 CLT 3/85 CLT 3/104 CLT 3/110 CLT 3/126 CLT 3/132 CLT 3/135

Layer 1, 8 GPa 20 mm 20 mm 20 mm 42 mm 45 mm 42 mm 45 mm 45 mm



Panel Self Weight (Static Load) 0.30 kPa 0.41 kPa 0.43 kPa 0.52 kPa 0.55 kPa 0.63 kPa 0.66 kPa 0.68 kPa

Panel Thickness 60 mm 82 mm 85 mm 104 mm 110 mm 126 mm 132 mm 135 mm

Removed CO2 from Atmosphere 5, 6, 7 - 48 kg/m3 - 66 kg/m3 - 68 kg/m3 - 83 kg/m3 - 88 kg/m3 - 100 kg/m3 - 106 kg/m3 - 108 kg/m3

Locked-in-Carbon of CLT Panel 5, 6, 7 - 15 kg/m3 - 20 kg/m3 - 21 kg/m3 - 26 kg/m3 - 27 kg/m3 - 31 kg/m3 - 33 kg/m3 - 33 kg/m3

Created CO2 by Equivalent Concrete Slab 5, 6, 7 + 25 kg/m3 + 34 kg/m3 + 35 kg/m3 + 43 kg/m3 + 45 kg/m3 + 51 kg/m3 + 45 kg/m3 + 55 kg/m3

CLT CO2 Benefit Compared to a Concrete Slab 73 kg/m3 99 kg/m3 103 kg/m3 126 kg/m3 133 kg/m3 151 kg/m3 160 kg/m3 163k kg/m3

CLT Panel Specifications

Table 2: Material Strength Properties*

Structural Properties Longitudinal Laminates Transverse Laminates

Modulus of Elasticity (MoE) 8 GPa 6 GPa

Bending Strength 14 MPa 10 MPa

Compression Parallel to Grain 18 MPa 15 MPa

Compression Perpendicular to Grain 8.9 MPa 8.9 MPa

Tension Strength 6.0 MPa 4.0 MPa

Nominal Shear 3.8 MPa 3.8 MPa

* Refer to NZS 3603: 1993

Table 3: EWP Feedstock Gauge Priority and Associated Commonly Available Post Processed Gauges

Feedstock Priority

Raw Gauge (mm)

Commonly Available Processed Thicknesses*

Commonly Available Ripped Thicknesses*

1 90x45

35 mm

40 mm

41 mm

42 mm

15 mm

17 mm

2

100x50

43 mm

45 mm

17 mm

19 mm

*Client accepts treatment retention based on volume of post planing below 40 mm in thickness.


Panel TitleCLT

5/100CLT

5/144CLT

5/150CLT

5/166CLT

5/172CLT

5/184CLT

5/188CLT

5/194CLT

5/205CLT

5/210CLT

5/216CLT

5/225

Layer 1, 8 GPa 20 mm 42 mm 45 mm 42 mm 45 mm 41 mm 42 mm 45 mm 41 mm 42 mm 45 mm 45 mm




Layer 5, 8 GPa 20 mm 42 mm 45mm 42 mm 45 mm 41 mm 42 mm 45 mm 41 mm 42 mm 45 mm 45 mm

Panel Self Weight (Static Load)

0.50 kPa 0.72 kPa 0.75 kPa 0.83 kPa 0.86 kPa 0.92 kPa 0.94 kPa 0.97 kPa 1.03 kPa 1.05 kPa 1.08 kPa 1.13 kPa

Panel Thickness 100 mm 144 mm 150 mm 166 mm 172 mm 184 mm 188 mm 194 mm 205 mm 210 mm 216 mm 225 mm

Removed CO2 from Atmosphere 5, 6, 7

- 76 kg/m3

- 110 kg/m3

- 115 kg/m3

- 127 kg/m3

- 131 kg/m3

- 141 kg/m3

- 144 kg/m3

- 148 kg/m3

- 157 kg/m3

- 161 kg/m3

- 165 kg/m3

- 172 kg/m3

Locked-in-Carbon of CLT Panel 5, 6, 7

- 24 kg/m3

- 34 kg/m3

- 35 kg/m3

- 39 kg/m3

- 41 kg/m3

- 43 kg/m3

- 44 kg/m3

- 46 kg/m3

- 48 kg/m3

- 49 kg/m3

- 51 kg/m3

- 53 kg/m3

Created CO2 by Equivalent Concrete Slab 5, 6, 7

+ 39kg/m3

+ 56kg/m3

+ 58kg/m3

+ 64 kg/m3

+ 67 kg/m3

+ 71 kg/m3

+ 73 kg/m3

+ 75 kg/m3

+ 80 kg/m3

+ 82 kg/m3

+ 84kg/m3

+ 87 kg/m3

CLT CO2 Benefit Compared to a Concrete Slab

115 kg/m3

166 kg/m3

173 kg/m3

191 kg/m3

198 kg/m3

212 kg/m3

217 kg/m3

224 kg/m3

236 kg/m3

242 kg/m3

249 kg/m3

259 kg/m3


Panel TitleCLT

7/140CLT

7/184CLT

7/215CLT

7/234CLT

7/240CLT

7/250CLT

7/256CLT

7/272CLT

7/294CLT

7/300CLT

7/305CLT

7/315








Panel Self Weight (Static Load)

0.70 kPa 0.92 kPa 1.08 kPa 1.17 kPa 1.20 kPa 1.25 kPa 1.28 kPa 1.36 kPa 1.47 kPa 1.50 kPa 1.53 kPa 1.58 kPa

Panel Thickness 140 mm 184 mm 215 mm 234 mm 240 mm 250 mm 256 mm 272 mm 294 mm 300 mm 305 mm 315 mm

Removed CO2

from Atmosphere 5, 6, 7

- 200 kg m3

- 263 kg/m3

- 307 kg/m3

- 334 kg/m3

- 342 kg/m3

- 357 kg/m3

- 365 kg/m3

- 388 kg/m3

- 419 kg/m3

- 428 kg/m3

- 435 kg/m3

- 449 kg/m3

Locked-in-Carbon of CLT Panel 5, 6, 7

- 62 kg/m3

- 82 kg/m3

- 96 kg/m3

- 104 kg/m3

- 107 kg/m3

- 111 kg/m3

- 114 kg/m3

- 121 kg/m3

- 131 kg/m3

- 134 kg/m3

- 136 kg/m3

- 140 kg/m3

Created CO2 by Equivalent Concrete Slab 5, 6, 7

+ 102kg/m3

+ 134 kg/m3

+ 156 kg/m3

+ 170 kg/m3

+ 174 kg/m3

+ 182 kg/m3

+ 186 kg/m3

+ 198 kg/m3

+ 213 kg/m3

+ 218 kg/m3

+ 221 kg/m3

+ 229 kg/m3

CLT CO2 Benefit Compared to a Concrete Slab

301 kg/m3

396 kg/m3

463kg/m3

504kg/m3

517kg/m3

538kg/m3

551 kg/m3

586 kg/m3

633 kg/m3

464 kg/m3

657kg/m3

678kg/m3

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CLT Roof Panel Specifications & Design Tables

Table 7a: 3 Layer CLT Roof Specification for No Snow Zone Areaa, b, c

Panel Title Thickness Simply Supported Cantilevered

CLT 3/104 104 mm 4.57 m 1.35 m

CLT 3/110 110 mm 4.77 m 1.40 m

CLT 3/126 126 mm 5.18 m 1.60 m

CLT 3/132 132 mm 5.38 m 1.65 m

CLT 3/135 135 mm 5.45 m 1.75 m

5 Layer Single Span CLT Panel

Applied Loads:Imposed Load = 0.25 kPaSnow Load = 0 kPa or 3 kPaCLT Dead Load = Refer to Table 5

3 Layer Single Span CLT Panel

Applied Loads:Imposed Load = 0.25 kPaSnow Load = 0 kPa or 3 kPaCLT Dead Load = Refer to Table 4

Table 7b: 3 Layer CLT Roof Specification under 3 kPa load for Snow Zone Areaa, b, c


CLT 3/104 104 mm 2.62 m 1.10 m

CLT 3/110 110 mm 2.77 m 1.15 m

CLT 3/126 126 mm 3.11 m 1.45 m

CLT 3/132 132 mm 3.22 m 1.48 m

CLT 3/135 135 mm 3.28 m 1.50 m

Table 8a: 5 Layer CLT Roof Specification for No Snow Zone Areaa, b, c,


CLT 5/100 100 mm 4.10 m 1.10 m

CLT 5/144 144 mm 5.68 m 1.45 m

CLT 5/150 150 mm 5.87 m 1.80 m

CLT 5/166 166 mm 6.25 m 1.85 m

CLT 5/172 172 mm 6.43 m 1.90 m

CLT 5/184 184 mm 6.49 m 2.05 m

CLT 5/188 188 mm 6.59 m 2.08 m

CLT 5/194 194 mm 6.78 m 2.00 m

CLT 5/205 205 mm 6.92 m 2.05 m

CLT 5/210 210 mm 7.04 m 2.15 m

CLT 5/216 216 mm 7.24 m 2.19 m

CLT 5/225 225 mm 7.40 m 2.25 m

Table 8b: 5 Layer CLT Roof Specification under 3 kPa load for Snow Zone Areaa, b, c


CLT 5/100 100 mm 2.35 m 1.00 m

CLT 5/144 144 mm 3.50 m 1.25 m

CLT 5/150 150 mm 3.65 m 1.50 m

CLT 5/166 166 mm 3.96 m 1.60 m

CLT 5/172 172 mm 4.11 m 1.70 m

CLT 5/184 184 mm 4.20 m 1.85 m

CLT 5/188 188 mm 4.28 m 1.87 m

CLT 5/194 194 mm 4.44 m 1.89 m

CLT 5/205 205 mm 4.58 m 1.90 m

CLT 5/210 210 mm 4.68 m 1.95 m

CLT 5/216 216 mm 4.84 m 1.98 m

CLT 5/225 225 mm 4.98 m 2.05 m

a) Not designed for floor applications. b) Designed for 0.25 kPa live load, 500 kg/m3 weight assumption for CLT panel,

0.1 kPa additional dead load for non-structural elements. Snow load assumed as the dead load in calculations.

c) Not designed for vibration.

a) Not designed for floor applications. b) Designed for 0.25 kPa live load, 500 kg/m3 weight assumption for CLT panel, 0.1 kPa additional dead load for non-structural elements. Snow load assumed as the dead load in calculations.c) Not designed for vibration.

Single Span 3 Layer CLT Roof

Cantilevered 3 Layer CLT Roof

Single Span 5 Layer CLT Roof

Did not check for Vibration

Cantilevered 5 Layer CLT Roof

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Single Span

Double Span (Continuous two spans)

Cantilevered

CLT Panel Specifications & Design Tables for Floor Applications

Table 9: 3 Layer Simply Supported Single Span, Double Span, and Cantilevered CLT Floor Specifications a, b, c, d, e, f

Panel Title

Applied Load (kPa)

Super Imposed Dead Load = 0.5 kPa Super Imposed Dead Load = 1 kPa Super Imposed Dead Load = 1.5 kPa

Live Load (Imposed Load) Live Load (Imposed Load) Live Load (Imposed Load)

2 kPa 3 kPa 5 kPa 2 kPa 3 kPa 5 kPa 2 kPa 3 kPa 5 kPa

Sing

le s

pan

CLT 3/104 3.32 m 3.11 m 2.81 m 3.06 m 2.08 m 2.67 m 2.87 m 2.75 m 2.55 m

CLT 3/110 3.50 m 3.28 m 2.96 m 3.23 m 3.06 m 2.81 m 3.03 m 2.90 m 2.69 m

CLT 3/126 3.82 m 3.59 m 3.27 m 3.54 m 3.37 m 3.12 m 3.33 m 3.19 m 2.98 m

CLT 3/132 3.97 m 3.78 m 3.43 m 3.73 m 3.54 m 3.26 m 3.50 m 3.36 m 3.13 m

CLT 3/135 4.02 m 3.84 m 3.49 m 3.79 m 3.61 m 3.32 m 3.56 m 3.42 m 3.18 m

Dou

ble

span

(Con

tinu

ous

two

sp

ans)

CLT 3/104 3.56 m 3.56 m 3.56 m 3.56 m 3.56 m 3.56 m 3.56 m 3.56 m 3.42 m

CLT 3/110 3.71 m 3.71 m 3.71 m 3.71 m 3.71 m 3.71 m 3.71 m 3.71 m 3.61 m

CLT 3/126 4.00 m 4.00 m 4.00 m 4.00 m 4.00 m 4.00 m 4.00 m 4.00 m 4.00 m

CLT 3/132 4.17 m 4.17 m 4.17 m 4.17 m 4.17 m 4.17 m 4.17 m 4.17 m 4.17 m

CLT 3/135 4.22 m 4.22 m 4.22 m 4.22 m 4.22 m 4.22 m 4.22 m 4.22 m 4.22 m

Cant

ilev

ered

CLT 3/104 0.30 m 0.28 m 0.20 m 0.25 m 0.23 m 0.19 m 0.20 m 0.18 m 0.14 m

CLT 3/110 0.34 m 0.32 m 0.21 m 0.28 m 0.25 m 0.20 m 0.22 m 0.20 m 0.15 m

CLT 3/126 0.38 m 0.36 m 0.24 m 0.31 m 0.28 m 0.23 m 0.24 m 0.22 m 0.17 m

CLT 3/132 0.39 m 0.37 m 0.25 m 0.32 m 0.29 m 0.24 m 0.25 m 0.23 m 0.18 m

CLT 3/135 0.40 m 0.38 m 0.26 m 0.34 m 0.31 m 0.25 m 0.26 m 0.24 m 0.19 m

a) Floors are designed for 2 kPa, 3 kPa or 5kPa Live Load (Imposed Load).b) Floors are designed for 0.5 kPa, 1 kPa or 1.5 kPa additional Dead Load (Super Imposed Dead Load).c) Floors are designed for 500 kg/m3 weight assumption for CLT panel (refer to Table 4).d) Floors are designed for vibration.e) RSWS design limits for floors are not constrained to this table. If specific floor designs are required, please contact RSWS.

Checked for Vibration

3 Layer CLT Panel

Single Span

Double Span (Continuous two spans)

Checked for Vibration

5 Layer CLT Panel

Cantilevered

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Table 10: 5 Layer Simply Supported Single Span, Double Span, and Cantilevered CLT Floor Specifications a, b, c, d, e

Panel Title

Applied Load (kPa)

Super Imposed Dead Load = 0.5 kPa Super Imposed Dead Load = 1 kPa Super Imposed Dead Load = 1.5 kPa

Live Load (Imposed Load) Live Load (Imposed Load) Live Load (Imposed Load)

2 kPa 3 kPa 5 kPa 2 kPa 3 kPa 5 kPa 2 kPa 3 kPa 5 kPa

Sing

le s

pan

CLT 5/100 2.95 m 2.76 m 2.48 m 2.58 m 2.58 m 2.36 m 2.44 m 2.44 m 2.26 m

CLT 5/144 4.21 m 4.05 m 3.69 m 3.81 m 3.81 m 3.52 m 3.62 m 3.62 m 3.37 m

CLT 5/150 4.35 m 4.22 m 3.84 m 3.97 m 3.97 m 3.66 m 3.77 m 3.77 m 3.52 m

CLT 5/166 4.65 m 4.58 m 4.11 m 4.31 m 4.31 m 3.99 m 4.10 m 4.10 m 3.83 m

CLT 5/172 4.80 m 4.74 m 4.33 m 4.47 m 4.47 m 4.14 m 4.25 m 4.25 m 3.94 m

CLT 5/184 4.83 m 4.79 m 4.38 m 4.52 m 4.52 m 4.19 m 4.30 m 4.30 m 4.02 m

CLT 5/188 4.91 m 4.88 m 4.47 m 4.82 m 5.61 m 4.27 m 4.56 m 4.38 m 4.10 m

CLT 5/194 5.05 m 5.05 m 4.62 m 4.98 m 4.77 m 4.42 m 4.72 m 4.54 m 4.25 m

CLT 5/205 5.19 m 5.19 m 4.79 m 5.15 m 4.93 m 4.58 m 4.88 m 4.70 m 4.40 m

CLT 5/210 5.29 m 5.29 m 4.89 m 5.26 m 5.04 m 4.68 m 4.98 m 4.80 m 4.50 m

CLT 5/216 5.43 m 5.43 m 5.05 m 5.43 m 5.20 m 4.83 m 5.14 m 4.96 m 4.65 m

CLT 5/225 5.56 m 5.56 m 5.19 m 5.56 m 5.35 m 4.98 m 5.29 m 5.10 m 4.79 m

Dou

ble

span

(Con

tinu

ous

two

span

s)

CLT 5/100 3.21 m 3.21 m 3.21 m 3.21 m 3.21 m 3.16 m 3.21 m 3.21 m 3.02 m

CLT 5/144 4.42 m 4.42 m 4.42 m 4.42 m 4.42 m 4.42 m 4.42 m 4.42 m 4.42 m

CLT 5/150 4.57 m 4.57 m 4.57 m 4.57 m 4.57 m 4.57 m 4.57 m 4.57 m 4.57 m

CLT 5/166 4.89 m 4.89 m 4.89 m 4.89 m 4.89 m 4.89 m 4.89 m 4.89 m 4.89 m

CLT 5/172 5.04 m 5.04 m 5.04 m 5.04 m 5.04 m 5.04 m 5.04 m 5.04 m 5.04 m

CLT 5/184 5.07 m 5.07 m 5.07 m 5.07 m 5.07 m 5.07 m 5.07 m 5.07 m 5.07 m

CLT 5/188 5.15 m 5.15 m 5.15 m 5.15 m 5.15 m 5.15 m 5.15 m 5.15 m 5.15 m

CLT 5/194 5.30 m 5.30 m 5.30 m 5.30 m 5.30 m 5.30 m 5.30 m 5.30 m 5.30 m

CLT 5/205 5.45 m 5.45 m 5.45 m 5.45 m 5.45 m 5.45 m 5.45 m 5.45 m 5.45 m

CLT 5/210 5.55 m 5.55 m 5.55 m 5.55 m 5.55 m 5.55 m 5.55 m 5.55 m 5.55 m

CLT 5/216 5.70 m 5.70 m 5.70 m 5.70 m 5.70 m 5.70 m 5.70 m 5.70 m 5.70 m

CLT 5/225 5.84 m 5.84 m 5.84 m 5.84 m 5.84 m 5.84 m 5.84 m 5.84 m 5.84 m

Cant

ilev

ered

CLT 5/100 0.27 m 0.24 m 0.15 m 0.21 m 0.17 m 0.11 m 0.17 m 0.14 m 0.09 m

CLT 5/144 0.46 m 0.43 m 0.25 m 0.36 m 0.34 m 0.18 m 0.27 m 0.23 m 0.14 m

CLT 5/150 0.49 m 0.46 m 0.27 m 0.38 m 0.36 m 0.19 m 0.30 m 0.24 m 0.15 m

CLT 5/166 0.50 m 0.47 m 0.29 m 0.39 m 0.37 m 0.21 m 0.31 m 0.26 m 0.17 m

CLT 5/172 0.51 m 0.48 m 0.30 m 0.40 m 0.38 m 0.22 m 0.32 m 0.28 m 0.18 m

CLT 5/184 0.52 m 0.49 m 0.31 m 0.41 m 0.39 m 0.23 m 0.33 m 0.30 m 0.19 m

CLT 5/188 0.55 m 0.51 m 0.32 m 0.42 m 0.40 m 0.24 m 0.34 m 0.31 m 0.20 m

CLT 5/194 0.58 m 0.54 m 0.33 m 0.44 m 0.41 m 0.25 m 0.35 m 0.33 m 0.21 m

CLT 5/205 0.70 m 0.63 m 0.35 m 0.53 m 0.47 m 0.25 m 0.39 m 0.35 m 0.21 m

CLT 5/210 0.71 m 0.65 m 0.36 m 0.54 m 0.50 m 0.26 m 0.41 m 0.36 m 0.22 m

CLT 5/216 0.72 m 0.67 m 0.37 m 0.55 m 0.52 m 0.27 m 0.42 m 0.38 m 0.23 m

CLT 5/225 0.75 m 0.70 m 0.38 m 0.57 m 0.53 m 0.28 m 0.43 m 0.40 m 0.24 m

a) Floors are designed for 2 kPa, 3 kPa or 5 kPa Live Load (Imposed Load).b) Floors are designed for 0.5 kPa, 1 kPa or 1.5 kPa additional Dead Load (Super Imposed Dead Load).c) Floors are designed for 500 kg/m3 weight assumption for CLT panel (refer to Table 5).d) Floors are designed for vibration.e) RSWS design limits for floors are not constrained to this table. If specific floor designs are required, please contact RSWS.

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CLT Panel Specifications for Wall ApplicationsCLT walls are vertical structural members, which are typically designed to carry gravity loads. Prefabricated CLT walls are

significantly lighter in weight compared with precast concrete walls, generally faster to install, and require less transportation and associated logistics management. CLT walls have excellent fire resistance and provide exceptional bracing attributes. The design calculations for CLT walls under axial loads are summarised in Tables 11a - 11b. RSWS is capable of manufacturing both industrial and architectural4 grade CLT wall systems, allowing the timber to be exposed to reduced secondary lining costs, improve aesthetics and the occupants’ health and well-being.

CLT Panel Specifications for Stair ApplicationsCLT stairs are a significantly more cost-effective, expedient, lighter and more versatile stair system. The performance specifications of

CLT stairs, generally allow them to be installed early in a project to provide safe access during the construction phase. Typically machined out of a solid CLT panel, CLT stairs provide a high strength, robust and visually appealing substrate that generally only requires supporting at both ends to create a clean, clear span (Figures 20 - 21). CLT stairs have an excellent fire rating due to the mass of the solid timber system.

The performance characteristics of the CLT stairs are created from the layers under the plane generated from the underside of the treads and risers (stringer). The machined section to create the treads and risers is effectively non-structural, but is still bonded as a homogenous system with the stringer section of the stair substrate. The CLT under the treads and risers is effectively the stair stringer, which is designed to be capable of handling the bending moment that is created with applied loads, and the self-weight of the stair system. The vibrational performance of the CLT stringer is also checked to confirm that the dynamic behavior of the CLT stairs is not creating an uncomfortable functional environment for the building occupants.

RSWS has the ability to optimise CLT stair designs based on architectural and structural requirements; however, standardised specifications are summarised in Table 12.

Table 11a: Wall Load Carrying Capacity of a 3 Layer CLT Panel Under Uniformly Distributed Vertical Load

Panel Title Wall Thickness Wall Height Removed CO2


CLT CO2 Benefit Compared to

a Concrete Slab2.4 m 3.0 m 3.6 m 4.0 m

CLT 3/104 104 mm 170 kN/m 140 kN/m 100 kN/m 40 kN/m - 83 kg/m3 126 kg/m3





Table 11b: Wall Load Carrying Capacity of a 5 Layer CLT Panel Under Uniformly Distributed Vertical Load

Panel Title Wall Thickness Wall Height Removed CO2


CLT CO2 Benefit Compared to

a Concrete Slab2.4 m 3.0 m 3.6 m 4.0 m




Figure 20: Example of RSWS manufactured stairs.

Figure 21: 3D view of typical CLT Stairs.

15

Table 12: CLT Stair Span a,b,c,d,e,f

Panel Title StringerThickness (mm)

Residential2 kPa

Commercial3 kPa

Removed CO2from Atmosphere

CLT Stairs CO2 BenefitCompare to Concrete

Stairs

CLT 3/82 82 mm 2.47 m 2.30 m -66 kg/m3 99 kg/m3

CLT 3/85 85 mm 2.54 m 2.36 m -68 kg/m3 103 kg/m3

CLT 3/104 104 mm 3.29 m 3.07 m -83 kg/m3 126 kg/m3

CLT 3/110 110 mm 3.46 m 3.24 m -88 kg/m3 133 kg/m3

CLT 3/126 126 mm 3.82 m 3.57 m -100 kg/m3 151 kg/m3

CLT 3/132 132 mm 3.97 m 3.74 m -106 kg/m3 160 kg/m3

CLT 3/135 135 mm 4.02 m 3.80 m -108 kg/m3 163 kg/m3

CLT 5/100 100 mm 2.92 m 2.72 m -76 kg/m3 115 kg/m3

CLT5/144 144 mm 4.21 m 4.02 m -110 kg/m3 166 kg/m3

CLT 5/150 150 mm 4.35 m 4.19 m -115 kg/m3 173 kg/m3

CLT 5/166 166 mm 4.65 m 4.54 m -127 kg/m3 191 kg/m3

CLT 5/172 172 mm 4.80 m 4.71 m -131 kg/m3 198 kg/m3

CLT 5/184 184 mm 4.83 m 4.75 m -141 kg/m3 212 kg/m3

CLT 5/188 188 mm 4.91 m 4.85 m -144 kg/m3 217 kg/m3

CLT 5/194 194 mm 5.05 m 5.01 m -148 kg/m3 224 kg/m3

CLT 5/205 205 mm 5.19 m 5.18 m -157 kg/m3 236 kg/m3

CLT 5/210 210 mm 5.29 m 5.29 m -161 kg/m3 242 kg/m3

CLT 5/216 216 mm 5.43 m 5.43 m -165 kg/m3 249 kg/m3

CLT 5/225 225 mm 5.56 m 5.56 m -172 kg/m3 259 kg/m3

a) CLT Stairs are designed for a 2 kPa or 3 kPa Live Load (Imposed Load).b) CLT Stairs are designed for 500 kg/m3 weight assumption for CLT panel (CLT Stringer and CLT Tread & Riser).c ) CLT Stairs are designed for vibration.d) RSWS can design CLT Stairs for various loading combinations not presented in Table 12. e) RSWS design limits for stairs are not constrained to this table. If specific stair designs are required, please contact RSWS.f ) The maximum tread and riser dead load is generated by a 280 mm tread depth and 190 mm riser height and is reflected in the calculations within Figure 22. All other tread/riser combinations reduce the dead loads incorporated in Figure 22.

Riser Height 110 mm to 190 mm

Tread Depth260mm to +360 mm

Figure 22: Pitchline, tread and riser dimensions for common and main private stair ways.

16

References1. https://www.thinkwood.com/building-better/health-well-being.2. https://www.worldgbc.org/news-media/WorldGBC-embodied-carbon-report-published.3. Client requests can be assessed and supported, but the client will need to have their engineering team sign off on all RSWS

modelling and calculations. RSWS will charge all requests out at its defined rates.4. Visual grade references an improved appearance, with a reduced average knot size only. Refer to additional grade information.5. https://www.wooddays.eu6. “The cement industry’s role in change”, Dr Robert McCaffrey, Global Cement & Lime Magazine.7. https://timberfirst.wordpress.com/category/solid-timber-cross-laminated-timber/page/2/

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53 Ingram Road, Rukuhia Hamilton 3282 NewZealand

Waipa State Mill RoadRotorua 3073New Zealand

www.redstag.co.nz

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