COMMERCIAL ROOFING

1. COMMERCIAL ROOFING Tapered Insulation Systems

2. Learning ObjectivesTapered Insulation Presentation • Tapered insulation – what is it? • Why do we use it? • Various designs from good to best • Crickets function and design • Specifying a good design

3. What, Why, and How? Tapered Insulation Systems

4. Tapered Insulation • Rigid roof insulation • Made from various materials • Polyiso • Extruded & Expanded Polystyrene • Perlite • Typically 2x4 or 4x4 panels • Provides r-value and slope • Typical slopes available • 1/8”/ft., ¼”/ft., ½”/ft. • Arranged by a designer into a tapered system to promote positive drainage

5. Why use a tapered insulation system? • Main Goal • Eliminate the amount of ponding/standing water on the membrane when the roof deck does not provide adequate slope

6. Why is it Important? Ponding may void the roofing warranty

7. Why is it Important? Prevents the potential for roof collapse from excess weight

8. Why is it Important? Prevents growth of vegetation, fungi, and bacteria.

9. Extends the overall life of a roofing system. Why is it Important?

10. Why is it Important? • National Agencies & Code Groups require a minimum slope • ¼”/ft. minimum in most cases • Provided by structure or a tapered insulation system • Ponds existing after 48 hours not acceptable to any of the major code bodies

11. Tapered Insulation Designs • Numerous possible designs even for the simplest roof • Individual job parameters determine which design is the best option 4-way slope Modified 4-way slope with cricket Valley & Cricket

12. One Way Slope to Gutter • Most basic design • Simple installation

13. Ridge Two Way Slope to Gutter • Second most basic design • Roof is cut in half which reduces the maximum thickness • Simple installation

14. Valley and Cricket to Drain • Commonly used design with drains • Cheapest material cost in most cases (versus 4-way slope design) • Potential small ponding along cricket edges (typical) • Not the most effective drainage design Potential ponding area

15. Modified 4-Way Slope to Drains • Second most effective drainage • Used when no overflow drains exists • If one drain is clogged the water can flow over to other drain

16. 4-Way Slope Design • Most effective drainage design (any compromise will effect performance) • Every tapered system should start with this design • Next step is to identify justifiable reasons to alter this layout

17. Common Attempt to Show a 4-Way Slope Design Randomly drawn valley lines at no specific angles

18. Zoom Window Correct Way to Show a 4-Way Slope Design

19. Zoom Window 4-Way Slope Design Valley Lines should be drawn at a 45 degree angle out of each drain

20. 45 Degree Valley Miter 45 degree angle

21. 4-Way Slope Design WHAT ARE VALID REASONS TO NOT USE A 4-WAY SLOPE DESIGN?

22. Reasons to Alter 4-Way Design Complex existing drain locations

23. Reasons to Alter 4-Way Design Constant perimeter height is required

24. Reasons to Alter 4-Way Design Multiple drains at low point with no overflow drains Overflow drains added

25. Reasons to Alter 4-Way Design When cost is a bigger issue than performance 4-Way Design -Most effective drainage -Higher material cost Valley & Cricket Design -Least effective drainage -Lower material cost

26. Reasons to Alter 4-Way Design Multiple roof top units prevent layout from draining

27. Tapered Crickets • Used on both: • Full tapered systems • Structurally sloped decks Tapered Cricket

28. Tapered Cricket Tapered Crickets • Also called: • Saddles • Hog Backs

29. Tapered Crickets • Secondary application of insulation used to divert water from roof top curbs, valleys, and low points to drains or scuppers Tapered Crickets

30. SLOPE OF CRICKET SLOPE OF CRICKET SLOPE OF TAPER RAIN SLOPE OF TAPER Tapered Crickets Secondary application of insulation used to divertwater from roof top curbs, valleys, and low points to drains or scuppers

31. Tapered Crickets

32. Types of Crickets

33. Types of Crickets

34. Types of Crickets ½ - Diamond Cricket

35. Types of Crickets

36. Types of Crickets

37. Tapered Crickets Incorrectly drawn crickets Correctly drawn crickets

38. Tapered Crickets

39. Tapered Crickets Portion of tapered panel that is field trimmed as waste 4x4 Tapered panel Crickets are created in the field by field trimming tapered panels as shown

40. Tapered Crickets

41. Full Diamond Cricket Full Diamond Cricket Uninstalled Portion Installed 4x4 Tapered Panels Tapered Crickets

42. Tapered Crickets RTU

43. Tapered Crickets

44. Parts of a Tapered Cricket Cricket Width (Points 4 to 5)

45. Parts of a Tapered Cricket Cricket Length (Points 1 to 2)

46. Parts of a Tapered Cricket The slope that is created by the structural deck, tapered insulation or a combination of the two.

47. Parts of a Tapered Cricket The slope of the cricket panels. Recommended to be at least twice the net Roof Surface Slope that exists. This ensures that the water is directed into the cricket valley.

48. Parts of a Tapered Cricket The net slope created along the edges of the cricket. (Points 4 to 1, 4 to 2, 5 to 2, & 5 to 1) This directs the water to the drains.

49. Tapered Crickets • Caution! • If not designed properly crickets can pond Tapered Cricket

50. Cricket Valley Slope Cricket Surface Slope Cricket Width Roof Surface Slope Cricket Valley Slope Three Main Contributors to the Working Effectiveness of a Cricket 1. Roof Surface Slope Crickets divert water, so the greater the Roof Surface Slope the better they will perform!