Fire Safety of Mass timber Buildings with CLT in USA

David Barber

Abstract


Multistory buildings using mass timber and cross-laminated timber (CLT) as the primary structural elements are being planned and constructed globally, with interest starting to gather momentum in the United States. Model building codes in the United States limit timber construction to a building height of 85 ft (25.9 m) because of concerns over fire safety and structural performance. Up to 85 ft, the mass timber can be exposed. Architects and developers in the United States are pushing boundaries, requesting mass timber structures are constructed as high-rises and that load-bearing mass timber such as CLT be exposed and not fully protected. This provides an opportunity for the application of recent fire research and fire testing on exposed CLT to be applied, and existing methods of analyzing the impact of fire on engineered timber structures to be developed further. Fire testing has shown that exposing large areas of CLT significantly impacts the heat release rate and fire duration. This article provides an overview of the code requirements for timber construction in the United States, provides methods for building approval for a high-rise timber structure, and summarizes recent CLT compartment fire testing that is informing the fire engineering process. Methods for solutions are also discussed.


Keywords


Mass timber, cross laminated timber, fire safety, fire testing, performance based design

Full Text:

PDF

References


Aguanno, M., 2013, “Fire Resistance Tests on Cross-Laminated Timber Floor Panels: An Experimental and Numerical Analysis”. Department of Civil and Environmental Engineering, Carleton University, Ottawa, Canada

American Society for Testing and Materials, 2015, “ASTM E84: Standard Test Method for Surface Burning Characteristics of Building Materials”

American Society for Testing and Materials, 2016, “ASTM E119: Standard Test Methods for Fire Tests of Building Construction and Materials”

American Wood Council, 2012, “Code Conforming Wood Design”, Leesburg, Virginia

American Wood Council, 2015, “National Design Specification for Wood Construction”, Leesburg, Virginia

American Wood Council, 2015a, “Calculating the Fire Resistance of Exposed Wood Members, Technical Report No. 10”, Leesburg, Virginia

Babrauskas, V., 2004, “Wood Char Depth: Interpretation in Fire Investigations” Presented at International Symposium on Fire Investigation, Fire Service College, Moreton-in-Marsh, United Kingdom

Barber D, Crielaard R, Li X (2016) Towards fire safe design

of exposed timber in tall timber buildings. In Proc. World

Conference of Timber Engineering, August 22-25, 2016,

Vienna, Austria.

British Standards (2013) Eurocode 1: Actions on structures

part 1-2: General actions—Actions on structures exposed

to fire. BS EN 1991-1-2:2002, incorporating amendments

to 2013.

Buchanan A (2001) Structural design for fire safety. John

Wiley and Sons.

City of New York (2014) 2014 construction codes. http://

www1.nyc.gov/site/buildings/codes/2014-constructioncodes.

page.

Craft ST, et al (2011) Investigation of the behaviour of CLT

panels exposed to fire. In Proc. 12th International Conference

Fire and Materials.

Crielaard R (2015) Self-extinguishment of cross-laminated

timber. Master’s Thesis report, Faculty of Civil Engineering

and Geosciences, Delft University of Technology.

Department of Commerce (1942) Building materials and

structures, report BMS92, fire resistance classification

of structures. National Bureau of Standards, report

of sub-committee on fire resistance classifications of

central housing committee on research, design and

construction.

Drysdale D (2011) An introduction to fire dynamics, 3rd Ed.

Wiley.

Emberley R, Gorska C, Bolanosa A, Lucherinia A, Solartea

A, Soriguera D, Gutierrez M, Humphreys K, Hidalgoa J,

Maluka C, Law A, Torero J (2017) Description of small

and large-scale cross laminated timber fire tests. Fire Saf J

:327-335.

Frangi A, et al (2008) Fire behaviour of cross-laminated solid

timber panels. Institute of Structural Engineering, ETH

Zurich, Zurich, Switzerland.

Hadden R, Bartlett A, Hidalgo J, Santamaria S, Wiesner F,

Bisby L, Deeny S, Lane B (2017) Effects of exposed

engineered timber on compartment fire dynamics. In Proc.

th International Association of Fire Safety Science

Symposium, June 10-16, 2017, Lund, Sweden.

Hox K, et al (2015) “Branntest av massivtre” SP fire research,

report A15101 (in Norwegian, translated by Arup).

International Code Council (ICC) (2015) International

building code.

Kimball A, Hoehler M, Su J (2017) Fire safety challenges of

tall wood—Report on cross laminated timber (CLT)

compartment fire tests. In NFPA Conference and Expo,

June 4-7, 2017, Boston, MA.

Karacabeyli E, Douglas B (2013) CLT handbook, US edition.

FPInnovations SP529-E.

Klippel M, Schmid J, Frangi A (2016) Fire design of CLT,

paper submitted for joint event of COST actions FP1402

and FP1404. KTH Stockholm.

McGregor C (2013)Contribution of cross laminated timber panels to room fires. Thesis, Department of Civil and Environmental Engineering, Carleton University, Ottawa, ON, Canada.

Medina A (2014) Fire resistance of partially protected crosslaminated timber rooms. Thesis, Faculty of Graduate and

Postdoctoral Affairs, Civil Engineering, Carleton University

Ottawa, ON, Canada.

National Fire Protection Association (NFPA) (2015) “Life

safety code” NFPA 101.

Reska P (2008) In-depth temperature profiles in pyrolyzing

wood. Thesis submitted for the degree of Doctor of Philosophy,

University of Edinburgh.

Underwriters Laboratories (2014) UL 263—Standard for fire

tests of building construction and materials.

United States Department of Agriculture (USDA)

(2015) Tall wood building competition. https://www.

rethinkwood.com/tall-wood-mass-timber/tall-woodcompetition.

Wilinder P (2010) Fire resistance in cross laminated timber.

Master’s thesis, J¨onk¨oping University, Jonkoping, Sweden.

White R (2016) Analytical methods for determining fire

resistance of timber members. In SFPE handbook of fire

protection engineering, 5th Ed.


Refbacks

  • There are currently no refbacks.