1. 1 Deterioration of Trusses and Roof Systems of Livestock Farm Buildings By Yves Choinière Ing., agr., P. Eng. CSBE: 08-117

2. 2 Introduction Deterioration of steel and wood components of farm building – Well known – Documented

3. 3 Case study #1: Finishing swine barn, Ontario – Power-natural ventilation versus 100 % natural ventilation #2: Nursery-finishing, Ontario – Mechanical ventilation #3: Finishing swine barn, Quebec – 100 % natural ventilation #4: Pullet rearing barn – Mechanical ventilation

4. 4 Case #1: Finishing swine barn

5. 5 Barn A – Power-natural ventilation, 1996 – Winter pit fans – Modular ceiling air inlets – Deep pit over slatted floor – Summer natural ventilation Barn B – 100 % natural ventilation, 1995 – Similar to barn A

6. 6

7. 7

8. 8

9. 9

10. 10

11. 11

12. 12

13. 13

14. 14

15. 15

16. 16

17. 17 Table of results, power-natural 1996 November 21, 2007 Exterior T° = 5°C, rain Attic measurementsIn-barn T°6-7° C15-16° C R.H. %60-65 %80-85 % NH 3 2-4 ppm15 ppm CO 2 600-700 ppm3 000 ppm

18. 18 Table of results, 100 % natural 1996 Attic measurementsIn-barn T°6-7° C15-16° C R.H. %70-75 %70 % NH 3 N\D15 ppm CO 2 400-500 ppm3 000 ppm

19. 19

20. 20

21. 21

22. 22

23. 23

24. 24

25. 25

26. 26 Observations Attic space contamination from the barn to the attic by : – Modular air inlets – Fan exhaust – Eave openings – Vapor barrier failure

27. 27 Case #2: Nursery-finishing barn

28. 28 Case #2: Nursery-finishing Mechanical ventilation – Ceiling modular air inlets – Sidewall fans – Open eave

29. 29

30. 30

31. 31

32. 32

33. 33

34. 34

35. 35 Table of results, 1997-1998 Attic measurementsIn-barn T°7-8° C21-22° C R.H. %75-80 %70-75 % NH 3 6-7 ppm16-17 ppm CO 2 700-800 ppm2 800-3 000 ppm

36. 36 Observations Attic space contamination : – Modular air inlets – Fan exhaust – Eave openings – Vapor barrier failure

37. 37 Case #3: Finishing swine naturally ventilated barn Natural ventilation – Alley scrappers – Eave openings – Attic ventilation

38. 38

39. 39

40. 40

41. 41

42. 42

43. 43

44. 44

45. 45 Observations Eave opening desing; minimum space Vapor barrier Chimney vapor tightness Ridge ventilator, snow + rain

46. 46 Case #4: Pullet rearing barn, 1976 Sidewall air inlets without attic contact Sidewall fan exhaust with wind stoppers

47. 47

48. 48

49. 49

50. 50

51. 51

52. 52

53. 53

54. 54 Conclusion Ceiling modular air inlets – Risk of attic backdraft – Sealed or negative pressure Sidewall exhaust fans – No eave openings above winter fans – Fans with winter hoods – Eave opening desing

55. 55 Conclusion Attic ventilation – Ridge ventilator – Eave openings, winter and summer – Fire stops

56. 56 Aknowledgements Greg Zimmer, Ontario André Lafrance, Quebec VicWest steel products