Fire Safe Use Of Wood In Buildings: Global Design Guide

Description

This book provides guidance on the design of timber buildings for fire safety, developed within the global network Fire Safe Use of Wood (FSUW) and with reference to Eurocode 5 and other international codes. It introduces the behaviour of fires in timber buildings and describes strategies for providing safety if unwanted fires occur. It provides guidance on building design to prevent any fires from spreading while maintaining the load-bearing capacity of structural timber elements, connections and compartmentation. Also included is information on the reaction-to-fire of wood products according to different classification systems, as well as active measures of fire protection, and quality of workmanship and inspection as means of fulfilling fire safety objectives. • Presents global guidance on fire safety in timber buildings • Provides a wide perspective, covering the whole field of fire safety design • Uses the latest scientific knowledge, based on recent analytical and experimental research results • Gives practical examples illustrating the importance of good detailing in building design Fire Safe Use of Wood in Buildings is ideal for all involved in the fire safety of buildings, including architects, engineers, firefighters, educators, regulatory authorities, insurance companies and professionals in the building industry. Cover Half Title Title Page Copyright Page Table of Contents Acknowledgements Contributors Foreword Introduction Chapter 1 Timber structures and wood products Scope of chapter 1.1 Types of building occupancy 1.1.1 Residential buildings 1.1.2 Office buildings 1.1.3 Educational buildings 1.1.4 Public buildings 1.1.5 Industrial buildings 1.2 Types of timber structure 1.2.1 Light timber frame construction 1.2.2 Post-and-beam construction 1.2.3 Mass timber construction 1.2.4 Long-span structures 1.2.5 Hybrid structures 1.2.6 Prefabricated elements and modules 1.3 Structural timber products 1.3.1 Sawn timber 1.3.2 Wood I-joists 1.3.3 Metal plate wood trusses 1.3.4 Structural composite lumber 1.3.5 Glued laminated timber 1.3.6 Mass timber panels 1.3.7 Wood-based panels 1.4 Conclusion References Chapter 2 Fire safety in timber buildings Scope of chapter 2.1 Fire safety goals 2.1.1 Life safety 2.1.2 Property protection 2.1.3 Insurance views 2.2 Special considerations for timber buildings 2.2.1 Influence of exposed timber surfaces 2.2.2 Exposed timber 2.2.3 Recent reports and guidance on fire safety in timber buildings 2.3 Fire development 2.3.1 Time–temperature curve 2.4 Designing for fire safety 2.4.1 Human behaviour 2.4.2 Access and equipment for firefighters 2.4.3 Fire detection 2.4.4 Active fire protection 2.4.5 Passive fire protection 2.5 Controlling spread of fire 2.5.1 Fire spread within room of origin 2.5.2 Fire spread to adjacent rooms on the same level 2.5.3 Fire spread to other storeys 2.5.4 Fire spread to other buildings 2.6 Fire safety design methods 2.6.1 Prescriptive codes and performance-based codes 2.6.2 Trade-offs/alternative fire design 2.7 Fire severity 2.7.1 Code environment 2.7.2 Fire design time 2.7.3 Calculation methods 2.8 Fire resistance 2.8.1 Objectives of fire resistance 2.8.2 Components of fire resistance Structural adequacy Integrity Insulation 2.8.3 Structural fire resistance 2.9 Timber protection 2.9.1 Encapsulation 2.9.2 Partial encapsulation 2.9.3 Time to start charring and encapsulation falloff times 2.10 Design for the full duration of the fire 2.10.1 Burnout 2.10.2 Design to withstand burnout 2.10.3 Self-extinguishment 2.10.4 Structural design to withstand burnout 2.10.5 Glueline failure 2.11 Special provisions for tall timber buildings 2.12 Fire safety during construction 2.13 Research needs References Chapter 3 Fire dynamics Scope of chapter 3.1 Introduction 3.2 Combustion of wood products 3.2.1 Effect of temperature and radiant heat 3.2.2 Flaming combustion 3.2.3 Smouldering combustion 3.3 Compartment fires 3.3.1 Fire development stages 3.3.2 Fire growth 3.3.3 Flashover 3.3.4 Fully developed fire 3.3.5 External flame projection 3.3.6 External fire spread to neighbouring buildings 3.3.7 Species production 3.4 Compartment fire temperatures 3.4.1 Energy and mass balance 3.4.2 Parametric/natural fires 3.4.3 Localised fires 3.4.4 Travelling fires 3.4.5 Standard fire resistance test 3.5 Fire experiments in CLT compartments 3.6 Other factors for timber compartments 3.6.1 Char fall-off 3.6.2 Protective coverings 3.6.3 Location of exposed or partially protected timber surfaces 3.6.4 Wind effects 3.7 Design to withstand burnout 3.7.1 Design intent 3.7.2 Burnout 3.8 Calculation methods for compartments with exposed timber 3.8.1 Methods using parametric fires 3.8.2 Compartment fire models that include wood pyrolysis 3.8.3 Time equivalence methods 3.8.4 Summary of fire severity models for mass timber buildings with exposed wood 3.9 Worked example 3.9.1 Description 3.9.2 Procedure 3.9.3 Experimental results 3.10 Research needs References Chapter 4 Fire safety requirements in different regions Scope of chapter 4.1 Regulatory control systems for fire safety in buildings 4.1.1 Europe 4.1.2 Canada 4.1.3 USA 4.1.4 China 4.1.5 Japan 4.1.6 Russian Federation 4.1.7 Australia Performance Solution Deemed-to-Satisfy Solution (DTS) 4.1.8 New Zealand 4.1.9 Other regions 4.2 International guides and standards 4.2.1 International Fire Engineering Guide (IFEG) 4.2.2 International standards 4.2.3 European guideline 4.3 National and regional differences for the use of wood 4.3.1 Residential buildings 4.3.1.1 Load-bearing timber elements 4.3.1.2 Visible wood surfaces 4.3.2 Office buildings 4.3.3 Differences between European countries 4.4 Conclusions References General Australia Canada China Europe Japan New Zealand Russian Federation USA Chapter 5 Reaction to fire performance Scope of chapter 5.1 Wood products used as interior finish, exterior cladding or roof covering 5.1.1 Sawn timber 5.1.2 Panel products 5.1.3 Engineered structural wood products 5.2 Assessing reaction to fire performance of wood products for compliance with prescriptive regulations 5.2.1 Wall and ceiling linings International methods Australia and New Zealand Europe Japan North America Comparison of reaction to fire classification of surface linings in different countries 5.2.2 Floor coverings International method Australia and New Zealand Europe North America 5.2.3 Roof coverings International method New Zealand Europe North America 5.2.4 Façade claddings International methods Australia and New Zealand Europe Japan North America 5.3 Reaction to fire characteristics of wood products for performance-based design 5.3.1 Ignitability Flaming ignition Glowing ignition 5.3.2 Surface spread of flame 5.3.3 Burning rate Heat release rate Pyrolysis models 5.3.4 Production rate of smoke and toxic products of combustion 5.4 Methods for improving the reaction to fire performance of wood products 5.4.1 Fire-retardant treatments, including surface coatings 5.4.2 Durability of reaction to fire performance References Chapter 6 Fire-separating assemblies Scope 6.1 General 6.2 Basic requirements for fire-separating assemblies 6.3 Encapsulation 6.4 Design methods for separating assemblies 6.4.1 Methods for determining the fire resistance of separating assemblies 6.4.2 Classification based on fire testing 6.4.3 Tabulated design data 6.4.4 Simplified calculation methods Separating Function Method (Europe) Component Additive Method (US/Canada) 6.4.5 Advanced calculation methods 6.5 Design of assemblies for compartmentation 6.5.1 Light timber frame walls and floors Insulation and lining materials Void spaces Mechanical impact Linings Gypsum plasterboards Cavity insulation Framing members 6.5.2 Mass timber wall and floor panels 6.5.3 Hollow core timber elements 6.5.4 Timber T-beam floors 6.5.5 Gaps for construction tolerances and shrinkage 6.5.6 Hybrid Timber–Concrete–Composite floors 6.5.7 Protection of floors to prevent fire spreading downwards from a fire above 6.5.8 Openings and penetrations in separating assemblies References Chapter 7 Load-bearing timber structures Scope of chapter 7.1 General 7.2 Estimation of structural loads 7.3 Assessment of fire resistance by testing 7.4 Assessment of fire resistance by calculation 7.5 Charring of timber and wood-based panels 7.5.1 Charring of unprotected timber 7.5.2 Charring of protected timber 7.5.3 One-dimensional charring 7.5.4 Two-dimensional charring 7.5.5 European Charring Model (ECM) Charring rates in the ECM Charring of linear structural members Charring of plane members 7.5.6 European Charring Model for light timber frame assemblies Cavity insulation Light timber frame with solid wood members Light timber frame with I-joists 7.5.7 Charring model in the United States 7.5.8 Charring model in Canada 7.5.9 Charring model in Australia and New Zealand 7.6 Materials for protection of timber structures 7.6.1 Wood-based protection materials 7.6.2 Gypsum boards 7.6.3 Clay plasters 7.6.4 Cement-based boards 7.6.5 Intumescent coatings 7.7 Effect of glueline failure 7.8 Calculation methods for standard fire exposure 7.8.1 Effective cross-section method in Eurocode 5 Strength and stiffness Effective cross-section Design of linear and plane timber members Design of light timber frame floor and wall assemblies 7.8.2 Effective cross-section method in Australia and New Zealand 7.8.3 Effective cross-section method in the United States Unprotected members Protected members 7.8.4 Effective cross-section method in Canada 7.9 Advanced calculation methods 7.10 Worked examples Calculations of glulam beam protected with fire-rated gypsum plasterboard 15 mm 7.10.1 Effective Cross-Section method (Europe) Effective cross-section: 7.10.2 Effective cross-section method (Canada) Effective cross-section: 7.10.3 Effective cross-section method (United States) 7.10.4 Summary References Chapter 8 Timber connections Scope of chapter 8.1 Introduction 8.2 Overview of beam-to-column connection typologies 8.2.1 Timber-to-timber connections 8.2.2 External metallic plates 8.2.3 Embedded metal plates 8.2.4 Fully concealed connectors 8.3 Mass timber panel connection typologies 8.3.1 Panel-to-panel: spline, half-lap 8.3.2 Panel-to-panel hold-down connections 8.3.3 CLT wall-to-floor panel connections 8.3.4 Hybrid CLT floor to structural steel frame 8.4 Elevated temperatures in timber connections 8.4.1 Review of fire testing results 8.4.2 Charring in connections 8.4.3 Influence of applied load 8.4.4 Loss of strength behind the char layer: influence of thermal penetration depth 8.4.5 Fire severity 8.5 Design for fire resistance 8.5.1 Failure modes 8.5.2 Beam-to-column bearing connections 8.5.3 Beam-to-column knife–plate connectors 8.5.4 Charring localised to screws 8.5.5 Glued-in dowels and rods 8.6 CLT panel-to-panel connections 8.6.1 Design for fire resistance 8.7 Connections with additional fire protection 8.7.1 Protection with fire-rated board systems 8.7.2 Protection using timber 8.7.3 Protection using intumescent paint 8.7.4 Timber-to-steel connections 8.8 Connection design methods 8.8.1 Char-rate methods 8.8.2 Acceptance criteria 8.8.3 Worked examples 8.8.4 Connection detailing 8.8.5 Guidance documents 8.9 Advanced calculation methods 8.9.1 Modelling of timber connections 8.9.2 Uncoupled models 8.9.3 Coupled thermo-mechanical models 8.10 Further research References Chapter 9 Prevention of fire spread within structures Scope of chapter 9.1 Introduction 9.2 Preventing fire spread by detailed design 9.2.1 Different types of timber constructions 9.2.2 Typical fire spread paths and principles to prevent fire spread Path I: fire spread through failure of separating elements Path II: fire spread through joints Path III: fire spread through junctions Path IV: fire spread through building services Path V: fire spread through concealed construction cavities 9.2.3 Construction tolerances 9.3 Fire spread via separating elements, joints and junctions 9.3.1 Fire resistance of separating elements 9.3.2 Fire resistance of joints between structural elements 9.3.3 Seismic gaps 9.4 Fire spread via building service installations and penetrations 9.4.1 General requirements of fire-stopping building services 9.4.2 Concepts of fire protection to building services in multi-storey buildings 9.4.3 Types of building service installations 9.4.4 Penetration fire–stopping systems for walls and floors 9.4.5 Service installations embedded within building elements 9.4.6 Service installation within protected shafts and ducts 9.4.7 Air ventilation ducts through walls and floors 9.4.8 Elevated temperature exhaust system penetrations through walls and floors 9.5 Fire spread via building cavities and ventilation gaps 9.5.1 Main principles to prevent spread of fire and smoke 9.5.2 External and internal wall cavities and suspended ceiling spaces 9.5.3 Cavities between elements of modular construction Guidelines for fire stops in modular constructions 9.6 Vertical fire spread in exterior facade cavities References Chapter 10 Active fire protection by sprinklers Scope of chapter 10.1 General concepts of active fire protection 10.2 Detection, alarm and smoke management systems 10.3 Sprinkler systems 10.3.1 Objectives of sprinkler systems 10.3.2 Components of sprinkler systems 10.3.3 Wet-pipe and dry-pipe fire sprinkler systems 10.3.4 Residential sprinkler systems 10.3.5 Water mist systems 10.3.6 Sprinklers in earthquake areas 10.4 Sprinkler effects on fire safety 10.4.1 Effects on fire development 10.4.2 Property protection by sprinklers 10.4.3 Life safety by sprinklers 10.4.4 Cost-benefit analysis 10.5 Sprinkler reliability, performance and effectiveness 10.5.1 Sprinkler reliability 10.5.2 Sprinkler effectiveness 10.5.3 Sprinkler management procedures 10.6 Fire safety design with sprinklers: implementation in different countries 10.6.1 Countries with sprinkler requirements for taller timber buildings 10.6.2 Countries with possibilities for alternative fire safety design with sprinklers Australia New Zealand Canada The United States Europe Finland Sweden 10.6.3 Examples of reduced fire precautions with sprinklers 10.7 Justification for reduced fire precautions with sprinklers 10.8 Conclusions References Chapter 11 Performance-based design and risk assessment Scope of chapter 11.1 Introduction 11.1.1 Performance-based design 11.1.2 Early developments 11.1.3 Overview of the fire safety design process 11.1.4 Pathways for demonstrating compliance 11.1.5 Sources of further information General References/International Standards Europe UK Australia New Zealand The United States 11.2 Hazard analysis and fire scenarios 11.2.1 Overview of hazard analysis process 11.2.2 Overview of fire scenarios 11.2.3 Rationalisation of fire scenarios for quantitative risk assessments 11.2.4 Rationalisation of fire scenarios for deterministic analyses 11.2.5 Prescribed fire scenarios 11.3 Application of analysis methods to timber construction 11.3.1 Hazard identification 11.3.2 Preliminary qualitative and quantitative analysis 11.3.3 Fire scenarios for quantitative risk assessment 11.3.4 Quantitative risk assessment of structure and barrier performance References Chapter 12 Robustness in fire Scope of chapter 12.1 Basics of structural robustness 12.2 Basics of robustness and fire safety engineering 12.3 Normative framework and robustness 12.4 Exposure types 12.5 Consequences resulting from a fire event 12.6 Evaluation of improvements performed in practice 12.6.1 Prevention of progressive collapse for the fire situation 12.6.2 Approaches for improved robustness for timber buildings 12.6.3 Improvement of the robustness for structural timber buildings 12.7 Design of timber buildings for reuse after a fire 12.8 Discussion and conclusion References Chapter 13 Building execution and control Scope of chapter 13.1 Introduction 13.2 Control of workmanship 13.2.1 Installation of fire protection measures 13.2.2 Installation of fire stops and cavity barriers 13.3 Inspection during construction 13.3.1 Inspection of passive fire protection measures 13.3.2 Inspection of active fire protection systems 13.3.3 Coordination of interacting trades 13.3.4 Documentation 13.4 Fire safety during construction 13.4.1 Recommended fire precautions during construction 13.5 Responsibility and enforcement 13.5.1 Responsible parties 13.5.2 Adoption and application 13.6 Preventive measures 13.6.1 Fire safety plan 13.6.2 Fire safety coordinator 13.6.3 Control of ignition sources Hot works Electrical equipment Smoking Other ignition sources and fuel sources 13.6.4 Control of combustible materials Stored and waste materials Storage of combustible building materials Exposed combustible materials during construction Protection of light timber frame construction 13.6.5 Prevention against arson 13.6.6 Liaison with fire authorities 13.6.7 Water supplies 13.6.8 Staff training and human activities Fire safety awareness Training and fire drills Fire checks 13.7 Fire detection and suppression 13.7.1 Alarm and detection 13.7.2 Active fire protection Portable fire extinguishers Automatic sprinkler system Hydrants 13.7.3 Compartmentation of the building 13.7.4 Protection of combustible construction 13.7.5 Protection of neighbouring buildings 13.7.6 Means of egress – Escape routes 13.7.7 Fire service access 13.8 Emergency procedures References Chapter 14 Firefighting considerations for timber buildings Scope of chapter 14.1 Introduction 14.2 Traditional fire knowledge 14.3 Fire service concerns related to mass timber buildings 14.4 Light timber frame construction 14.4.1 Light timber frame structures with solid timber members 14.4.2 Light timber frame structures with engineered wood products 14.4.3 Charring in protected light timber frames 14.5 Mass timber structures 14.5.1 Strategies for protection of mass timber structures 14.5.2 Exposed timber structures 14.5.3 Combustible linings 14.5.4 CLT structures 14.6 Tall timber buildings 14.6.1 Sprinkler systems 14.6.2 Firefighter access 14.6.3 Burnout 14.7 Firefighting considerations 14.7.1 Firefighting water supplies 14.7.2 External fire exposure to surrounding buildings 14.7.3 Combustible cores and vertical enclosures 14.7.4 Void spaces and cavities 14.7.5 Identifying voids and fires within voids 14.7.6 Extinguishing fires within a void 14.7.7 Extinguishing fires in wood‐based materials 14.7.8 Extinguishing agents 14.7.9 Non-direct attack 14.7.10 Comparison of extinguishing equipment 14.8 Wind-driven fires 14.8.1 Influence of wind on fire intensity 14.9 Design stage and fire service involvement 14.9.1 Liaison with fire authorities 14.10 Pre-incident planning 14.10.1 Tall timber buildings 14.10.2 Fire service involvement during construction and demolition 14.10.3 Fire system impairment 14.10.4 Fire service site training and familiarisation 14.11 Post-earthquake fires and fire service response 14.12 Future needs References Index