A major problem in light-weight timber floors is their insufficient performance coping with impact noise in low frequencies. There are no prefabricated solutions available in Australia and New Zealand. To rectify this and enable the implementation of light-weight timber floors, a structural floor was designed and built in laminated veneer lumber (LVL). The floor was evaluated in a laboratory setting based on its behaviour and then modified with suspended ceilings and different floor toppings. Twenty-nine different floor compositions were tested. The bare floor could not reach the minimum requirement set by the Building Code of Australia (BCA) but with additional layers, a sufficient result of R'w+Ctr 53 dB and L’nT,w + CI 50 dB was reached. Doubling of the concrete mass added a marginal improvement. With concrete toppings and suspended ceiling it is possible to reach the goal in airborne and impact sound insulation. The best result was achieved by combining of additional mass and different construction layers.
This project aims to support the construction of tall wood buildings by identifying encapsulation methods that provide adequate protection of mass timber elements; the intention is that these methods could potentially be applied to mass timber elements so that the overall assembly could achive a 2 h fire resistance rating.
The following topics in the field of seismic analysis and design of mid-rise (5- and 6-storey) wood-frame buildings are included in this paper: Determination of the building period, linear dynamic analysis of wood-frame structures, deflections of stacked multi-storey shearwalls, diaphragm classification, capacity-based design for woodframe...
FPInnovations initiated this project to demonstrate the ability of wood exit stairs in mid-rise buildings to perform adequately in a fire when NBCC requirements are followed, with the intent of changing perceptions of the fire safety of wood construction. The objective of this research is to investigate further the fire safety afforded by exit stair shafts of combustible construction, with the ultimate objective of better consistency between the provincial and national building codes with respect to fire requirements for exit stair shafts in mid-rise wood-frame construction.
In this project, a conceptual but realistic 20-storey building of hybrid construction incorporating massive timber panels and other structural materials was identified. The project team, consisting of three practicing consultants and 6 graduate student and post-doctoral researchers from NEWBuildS, undertook an analysis and engineering design of the demonstration building. An advisory group that includes FPInnovations scientists, NEWBuildS supervisors of the graduate students and Post Doctoral Fellows, provides technical support to the project team. The performance attributes addressed in the project were structural performance under seismic and wind load, fire resistance and building envelope. . This publication documents the analysis and design of the demonstration building, and identifies technical issues that require further study.
This report begins with a discussion of the mechanisms of flame spread over combustible materials while describing the NBCC prescriptive solutions that establish the acceptable fire performance of interior finish materials. It is noted that while flame spread ratings do give an indication of the fire performance of products in building fires, the data generated are not useful as input to fire models that predict fire growth in buildings.
The cone calorimeter test is then described in some detail. Basic data generated in the cone calorimeter on the time to ignition and heat release rates are shown to be fundamental properties of wood products which can be useful as input to fire models for predicting fire growth in buildings.
The report concludes with the recommendation that it would be useful to run an extensive set of cone calorimeter tests on SCL, glue-laminated timber and CLT products. The fundamental data could be most useful for validating models for predicting flame spread ratings of massive timber products and useful as input to comprehensive computer fire models that predict the course of fire in buildings. It is also argued that the cone calorimeter would be a useful tool in assessing fire performance during product development and for quality control purposes.
The goal of this project is to contribute to the development of design values for cross-laminated timber (CLT) diaphragms in the seismic load-resisting system for buildings. Monotonic and cyclic tests to determine strength and stiffness characteristics of 2.44 m (8 ft) long shear connections with common self-tapping screws were performed. Understanding and quantifying the behavior of these shear connections will aid in developing design provisions in the National Design Specification for Wood Construction and the International Building Code so structural engineers can use CLT more confidently in lateral force-resisting systems and extend the heights of wood buildings. Experimental strength-to-design strength ratios were in the range of 2.1 to 8.7. In the ASCE 41 acceptance criteria analysis, the m-factors for the Life Safety performance level in cyclic tests ranged from 1.6 to 1.8 for surface spline connections and from 0.9 to 1.7 for cyclic half-lap connections. The half-lap connections, where screws were installed in withdrawal, shear, shear, and withdrawal, performed exceptionally well with both high, linear-elastic, initial stiffness, and ductile, post-peak behavior.
The role of the building envelope research team in this project was to assess whether midrise wood-frame (LWF) and cross-laminated timber (CLT) building envelope solutions developed by the fire research team to meet the fire provisions of the National Building Code (NBC) 2010 Part 3 Fire Protection, would also meet the NBC Part 5 Environmental Separation requirements relating to the protection of the building envelope from excessive moisture and water accumulation. As well, these wood-based mid-rise envelope solutions were to be assessed for their ability to meet Part 3 Building Envelope of the National Energy Code for Buildings (NECB) 2011. Requirements relating to heat, air, moisture, and precipitation (HAMP) control by the building envelope are included in Part 5 Environmental Separation of the NBC 2010. Part 5 addresses all building types and occupancies referred to in Part 3, but unlike requirements for fire protection, this section of the code was written more recently and is generic, including requirements that are more objective-oriented rather than prescriptive requirements pegged to specific constructions systems. The investigated methodologies developed and adapted for this study took those code characteristics into account.
There has been no research to date exploring whether timber products can provide effective thermal capacitance in residential or commercial construction. This research is exploring the use of unique mass-timber products to provide a new form of thermal performance capacitance within the built fabric of new and existing homes. The development of mass timber products is a new paradigm in material and building science research in Australia, requiring the accounting for carbon emissions, carbon sequestration, material embodied energy and material thermal properties for this renewable resource. This paper focuses on the results from preliminary building simulation studies encompassing house energy rating simulations and a comparative analysis of embodied energy and carbon storage for a series of house plans in Australia.
The objective of the task is to select, from the 679 locations in Table C-2 of the 2010 National Building Code of Canada (NBC 2010), several representative locations for which long-term historical weather data exists. This information from these locations can subsequently be used to determine the exterior boundary conditions for input files for hygrothermal simulation programs and hygrothermal testing in the laboratory.
This report discusses the selection of locations for the hygrothermal simulation task of the project on Mid-rise Wood Buildings and the determination of spray-rates and pressure differentials for the water penetration testing portion of the project.