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.
FPInnovations conducted a research project to study the construction of mid-rise wood exit shafts in Ontario and Québec. The scope of the project included an investigation into the concerns that have been raised in regards to the use of wood exits in mid-rise buildings, an analysis of recent Canadian fire statistics in residential multi-family structures, and a fire demonstration of a mass timber wall and supported light-frame floor. This report describes the fire demonstration completed as part of this project; this report acts as a supplement to the full project report.
Lack of research and design information for the seismic performance of balloon-type CLT shear walls prevents CLT from being used as an acceptable solution to resist seismic loads in balloon-type mass-timber buildings. To quantify the performance of balloon-type CLT structures subjected to lateral loads and create the research background for future code implementation of balloon-type CLT systems in CSA O86 and NBCC, FPInnovations initiated a project to determine the behaviour of balloon-type CLT construction. A series of tests on balloon-type CLT walls and connections used in these walls were conducted. Analytical models were developed based on engineering principles and basic mechanics to predict the deflection and resistance of the balloon-type CLT shear walls. This report covers the work related to development of the analytical models and the tests on balloon-type CLT walls that the models were verified against.
The latest developments in seismic design philosophy have been geared towards developing of so called "resilient" or "low damage" innovative structural systems that can reduce damage to the structure while offering the same or higher levels of safety to occupants. One such innovative structural system is the Pres-Lam system that is a wood-hybrid system that utilizes post-tensioned (PT) mass timber components in both rigid-frame and wall-based buildings along with various types of energy disspators. To help implement the Pres-Lam system in Canada and the US, information about the system performance made with North American engineered wood products is needed. That information can later be used to develop design guidelines for the designers for wider acceptance of the system by the design community.Several components influence the performance of the Pres-Lam systems: the load-deformation properties of the engineered wood products under compression, load-deformation and energy dissipation properties of the dissipators used, placement of the dissipators in the system, and the level of post-tensioning force. The influence of all these components on the performance of Pres-Lam wall systems under gravity and lateral loads was investigated in this research project. The research project consisted of two main parts: material tests and system tests.
This report addresses serviceability issues of tall wood buildings focusing on vibration and sound insulation performance. The sound insulation and vibration performance may not affect building's safety, but affects occupants' comfort and proper operation of the buildings and the funciton of sensitive equipment, consequently the acceptance of midrise and tall wood buildings in market place. Lack of data, knowledge and experience of sound and vibration performance of tall wood buildings is one of the issues related to design and construction of tall wood buildings.
For wood floor systems, their vibration performance is significantly dependent on the conditions of their supports, specifically the rigidity of the support. Detrimental effects could result if the floor supports do not have sufficient rigidity. This is special ture for floor supporting beams. The problem of vibrating floor due to flexible supporting beams can be solved through proper design of the supporting beams. However, there is currently no criterion set for the minimum requirement for floor supporting beam stiffness to ensure the beam is rigid enough. Designers’ current practice is to use the uniform load deflection criteria specified in the code for designing the supporting beams. This criterion is based on certain ratios of the floor span (e.g. L/360, L/480 etc.). The disadvantage of this approach is that it allows larger deflections for longer-span beams than for shorter beams. This means that engineers have to use their experience and judgement to select a proper ratio, particularly for the long-span beams. Therefore, a better vibration-controlled design criterion for supporting beams is needed.
It is recommended to further verify the ruggedness of the proposed stiffness criterion for floor supporting beams using new field supporting beam data whenever they become available.
Serviceability performance studied covers three different performance attributes of a building. These attributes are 1) vibration of the whole building structure, 2) vibration of the floor system, typically in regards to motions in a localized area within the entire floor plate, and 3) sound insulation performance of the wall and floor assemblies. Serviceability performance of a building is important as it affects the comfort of its occupants and the functionality of sensitive equipment as well. Many physical factors influence these performances. Designers use various parameters to account for them in their designs and different criteria to manage these performances. Lack of data, knowledge and experience of sound and vibration performance of tall wood buildings is one of the issues related to design and construction of tall wood buildings.
In order to bridge the gaps in the data, knowledge, and experience of sound and vibration performance of tall wood buildings, FPInnovations conducted a three-phase performance testing on the Origine 13-storey CLT building of 40.9 m tall in Quebec city. It was the tallest wood building in Eastern Canada in 2017.
A research project, Wood and Wood-Hybrid Midrise Buildings, was undertaken to develop information to be used as the basis for alternative/acceptable solutions for mid-rise construction using wood structural elements. As part of this project, four large-scale fire experiments were conducted to evaluate the fire performance of two forms of encapsulated combustible structural wood systems, a lightweight wood-frame (LWF) system (2 experiments [3, 4]) and a crosslaminated timber (CLT) system (1 experiment). The fourth experiment  involved a test structure constructed using a steel frame system described below. Each experiment involved construction of a test set-up of an unsprinklered full-size apartment unit, intended to represent a portion of a mid-rise (e.g. six-storey) building.
The structural elements used in the LWF system (wood stud walls and wood I-joist floors) and CLT system (3-ply wall panels and 5-ply floor panels) were all chosen on the basis of the types of construction that were currently being used in 5- and 6-storey mid-rise residential construction being built in the province of British Columbia, where the building code had changed earlier, in 2009, to permit such mid-rise combustible construction. This report provides the results of the experiment with an encapsulated CLT setup representing an apartment in a mid-rise (e.g. six-storey) building.
This project assesses the fire resistance of laminated timber structural systems as wall and floor assemblies. Full-scale tests were conducted to assess structural fire resistance and charring behaviour. This research could be used to expand current fire design provisions and support inclusion of these types of assemblies into Annex B of CSA O86.