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.
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.
A full-scale demonstration fire was conducted at National Research Council Canada (NRCC) to show that a 2-hr non-standard severe design fire in an apartment would have little or no effect on an adjacent elevator or stair shaft. The test was performed to support the approval of an alternative solution for a deemed-to-satisfy 2-hr...
As 6-storey wood-frame, massive-timber and hybrid wood buildings are increasingly accepted by more jurisdictions across Canada, there is a need to develop reliable elevator shaft designs that meet the minimum structural, fire, and sound requirements in building codes. Elevator shaft walls constructed with wood-based materials have the advantages of material compatibility, use of sustainable materials, and ease of construction.
In this exploratory study, selected elevator shaft wall designs built with nail-laminated-timber (NLT) structural elements were tested to investigate their sound insulation performance because little is known about the sound insulation performance of such wall assemblies. The tests were carried out in an acoustic mock-up facility in accordance to standard requirements, and provide preliminary data on the sound insulation performance of elevator shaft walls built with NLT panels.
Four different elevator shaft walls built with NLT panels were tested and their measured apparent sound insulation class (ASTC) ratings ranged from 18 to 39 depending on their construction details. Some of the reasons that may have contributed to the ASTC ratings obtained for the elevator shaft walls described in this report as well as recommendations for future designs were provided.
It is recommended to continue improving the sound insulation of elevator shaft walls built with NLT panels to meet or exceed the minimum requirements in building codes.
A full-scale demonstration dire was conducted at National Research Council Canada to show how a mass timber vertical shaft could withstand a severe fire exposure lasting at least two hours. The fire resistance tests and the demonstration fire were performed to support the approval and construction of a tall wood building in Quebec city; the building is planned to be 13 storeys which includes a 12-storey wood structure above a 1-storey concrete podium. An updated calculation methologody to determine the fire resistance of CLT is provided in Capter 8 (Fire) of the CLT Handbook.
New Zealand Society for Earthquake Engineering Conference
Research Status
Complete
Notes
April 26-28, 2013, Wellington, New Zealand
Summary
This paper describes options for seismic design of pre-fabricated timber core-wall
systems, used as stairwells and lift shafts for lateral load resistance in multi-storey timber
buildings. The use of Cross-Laminated Timber (CLT) panels for multi-storey timber buildings is
gaining popularity throughout the world, especially for residential construction. This
paper describes the possible use of CLT core-walls for seismic resistance in open-plan
commercial office buildings in New Zealand. Previous experimental testing at the
University of Canterbury has been done on the in-plane behaviour of single and coupled
Pres-Lam post-tensioned timber walls. However there has been very little research done
on the behaviour of timber walls that are orthogonal to each other and no research into
CLT walls in the post-tensioned Pres-Lam system. This paper describes the proposed test regime and design detailing of two half-scale twostorey CLT stairwells to be tested under a bi-directional quasi-static loading. The test specimens will include a half-flight stair case with landings within the stairwell. The “High seismic option” consists of post-tensioned CLT walls coupled with energy dissipating U-shaped Flexural Plates (UFP) attached between wall panels and square hollow section steel columns at the corner junctions. An alternative “Low seismic option” uses the same post-tensioned CLT panels, with no corner columns or UFPs. The panels will be connected by screws to provide a semi-rigid connection, allowing relative
movement between the panels producing some level of energy dissipation.
