Fire Safety Engineering David Barber, Principal, Australasia Fire Leader, ARUP Internationally and locally, timber and wood products are increasingly specified for major construction projects as a fire safe building material. Integrating design principles and fire engineering can ensure the required performance and compliance with relevant building codes.

2. Does Wood Burn ? The Fire Safety of Solutions in Wood David Barber Arup Fire Group Leader - Australasia Region

3. David BarberDoes Wood Burn ? The Fire Safety of Solutions in Wood

4. Does Wood Burn ? I have the hardest job - convince the audience that it is ok to have elements within a building that burn, even the structure

5. Does Wood Burn ? Wood burns – how it burns is important

6. Concept 1:Can Fire Performance Be Predicted ?

7. Concept 1:Can Fire Performance Be Predicted ? Fire performance of wood has been studied for many years: Research dates back to 13th century Solid wood has highly predictable performance in fire Little variability between countries in species type Knowledge = data = confidence

8. Concept 2:Not All Wood Is The Same

9. Concept 2:Not All Wood Is The Same

10. Concept 2:Not All Wood Is The Same

11. Concept 2:Not All Wood Is The Same

12. Concept 2:Not All Wood Is The Same I Scale Matters !

13. Concept 3:How Does Wood Burn ?

14. Concept 3:How Does Wood Burn ? Char: Natural protection for wood Allows for continued, but diminishing strength during a fire Well studied and well understood and is predictable Different wood – different char (due to density and water content)

15. Concept 3:How Does Wood Burn ? The importance of char:

16. Concept 4:Expected Fire Performance

17. Concept 4:Expected Fire Performance National Construction Code: Performance Requirement CP 1 - “A building must have elements which will, to the degree necessary, maintain structural stability during a fire appropriate to.......” Structural wood needs to provide an equivalent level of performance as concrete or steel

19. Exposed steel

20. Bending

22. Protection limits heat

23. Unlikely to collapse

25. Unlikely to collapse

27. Concepts:Summary Concepts for fire performance of wood: Fire performance is well understood Not all wood is the same - scale matters Solid wood chars – which has predictable performance in fire In a fully developed fire, wood can perform equivalent or better than steel

28. What Does the NCC Allow for Solutions in Wood ?

30. Class 2 or 3 (residential) – Rise in storeys of 3 or moreType A - all elements must be non-combustible (except a mezzanine), hence no wood permitted.......

31. What Does the NCC Allow for Solutions in Wood ? So, how is wood used in buildings ? NCC allows fire engineering solutions for areas of non-compliance (so called “performance based” approach) Fire engineering solutions will need a good fire engineer, who understands structural wood solutions, understands the process of approval and design implementation

32. Solutions in Wood - Facades

33. Solutions in Wood – Facades

34. Solutions in Wood – Internal Elements

35. Case Study – 5 Storey Building

37. Smoke detection

38. Sprinkler protection

40. Case Study – 5 Storey Building Solid wood structure of columns and beams, inherent FRL with load bearing capacity in excess of 60 mins FRL Wood assumed to not have any plasterboard protection (not required to be maintained) Steel would require protective coating (sprayed or paint) to achieve 60 mins FRL (requiring maintenance)

42. Floor and structure connections

43. Edge detailsPenetrations for building services are complex to solve Facade interface with wood edge beams are problematic

44. Case Study – 5 Storey Building Case study summary: Performance requirements of the NCC can be met using structural wood Designs can gain approval, provided the engineering is substantive Similar approach to any other fire engineered solution

45. Summary Wood does burn – but we understand how Structural wood is equivalent or better than structural steel in many built situations A lack of understanding of the fire performance of wood by many Wood can be used, but you need a fire engineering solution

46. Does Wood Burn ? The Fire Safety of Solutions in Wood Questions? David Barber Arup Fire Group Leader – Australasia Region