Splay End Hip

1. Splay End Hip Advanced Roofing

2. Roof Set Out

3. Hips always bisect corners

4. Centre an arc on the origin of the 2 lines you want to Bisect Scribe to cut external walls

5. Centre 2 arcs on the intersection of the lines you want To bisect & the previous scribed arc Radii need not be the same as the previous arc but both must be equal

6. Centre 2 arcs on the intersection of the lines you want To bisect & the previous scribed arc Both arcs must cross Radii need not be the same as the previous arc but both must be equal

7. Extend a line from the origin of the corner to be bisected thru the furtherest intersection of the arcs

8. The line formed has bisected the corner

9. The line formed has bisected the corner

10. Repeat the process for the other corner

15. Oblique End Roof

16. Roof Geometry

17. Roof Geometry If we extend ridge (which is central) it will intersect with centre of splay end

18. Roof Geometry Two Similar Triangles will be formed, 1 half the size of the other

19. Roof Geometry Remember for later Therefore we can say the ridge extension length is half the length of the splay end extension

20. Roof Geometry Remember for later We need to remember this number for later use

21. Roof Geometry Determine relevant triangle Walls are parallel

22. Roof Geometry Tan y = Opp/ Adj Tan y = 2000 / 900 Walls are parallel

23. Roof Geometry Tan y = 2.222 Angle y = 65.8⁰ Walls are parallel

24. Roof Geometry Angle Z =180 – 90 - 65.8⁰ Walls are parallel

25. Roof Geometry Angle Z =180 – 90 - 65.8⁰ Walls are parallel

26. Roof Geometry Angle Z = 24.2⁰ Walls are parallel

27. Roof Geometry Angle X = 24.2⁰ + 90⁰ Walls are parallel

28. Roof Geometry Walls are parallel

29. Roof Geometry Walls are parallel

30. Roof Geometry Note the 2 angles must add up to 90⁰

31. Roof Geometry This angle = 90 – 57.1⁰ Walls are parallel

32. Roof Geometry This angle = 90 – 32.9⁰

33. Roof Geometry A straight lines = 180⁰

34. Roof Geometry 180⁰ - 57.1⁰ - 32.9⁰ = 90⁰ Walls are parallel

35. Roof Geometry Therefore we can say When the corners of a splayed end roof are bisected they will intersect at the ridge The angles formed by the hips will be 90⁰ x 90⁰ x 90⁰ -x 90⁰ x 90⁰ - x 90 90⁰ - x

36. Roof Geometry If we centre a circle on the intersection of the Ridge & skew end = Then make the diameter the length Of the skew end The circle will pass thru the corners =

37. Roof Geometry Geometric Rule Lines from each end of a diameter that intersect on the circumference of the Circle will intersect at 90⁰ = =

38. Roof Geometry If we extend lines from these intersections To the centre of the circle = =

39. Roof Geometry If we extend lines from these intersections To the centre of the circle They must be radii = = = = =

40. Roof Geometry The ridge line extended past the centring Rafter must be a radius of this circle

41. Roof Geometry The Ridge Extension must equal the half length of the Splay end = = =

42. Roof Geometry = = =

43. Roof Geometry Previously we determined that the length of The ridge extension was half the splay end extension = = =

44. 1. Determine Splay Extension Splay Extension = Long Side – Short Side

45. 1. Confirmation of Learning Determine Splay Extension Splay Extension = Long Side – Short Side

46. 1. Confirmation of Learning Determine Splay Extension - Answer Splay Extension = 14162 – 11329

47. 2. Determine Splay End Length Splay End Length = √((Splay Extension)2 + (Span)2)

48. 2. Confirmation of Learning Determine Splay End Length Splay End Length = √(Splay Extension)2 + (Span)2)

49. 2. Confirmation of Learning Determine Splay End Length - Answer Splay End Length = √(Splay Extension)2 + (Span)2)

50. Positioning Centring Rafter Therefore the offset must equal Radius – Half the Splay Extension = = =