12 Sided Polygon Rafter Table ( 12 - gon )


central angle = 30
working angle = 15
plan angle = 75
miter angle = 3.22 & 12 (15.00)
hip run per foot = 12.42
apothem multiplier = 1.03528
side wall multiplier = 0.53590

Pitch

Roof Angles

Frieze Block Angles

Hip Rafters

Jack Rafters

Roof Pitch

Angle

Hip Pitch

Angle

Angle

Saw Bevel

Side Cut

Angle

Backing Angle

Hip Drop

2x

Hip Drop

4x

Length

Per-FT

Side Cut

Angle

First
12 O.C.

First
16 O.C.

First
24 O.C.

Spaced
12 O.C.

Spaced
16 O.C.

Spaced
24 O.C.

Multiplier

0

0.00

0.00

0

15

15.00

0.00

0.00

0.00

12.42

15

47.48

62.41

92.27

44.78

59.71

89.57

3.73205

1

4.76

4.60

1.27

14.95

14.95

1.23

0.02

0.04

12.46

14.95

47.65

62.63

92.59

44.94

59.92

89.88

3.74499

2

9.46

9.15

2.52

14.79

14.82

2.44

0.03

0.08

12.58

14.80

48.14

63.27

93.54

45.40

60.54

90.80

3.78353

3

14.04

13.58

3.72

14.54

14.60

3.60

0.05

0.11

12.78

14.57

48.95

64.33

95.11

46.16

61.55

92.33

3.84691

4

18.43

17.85

4.84

14.21

14.31

4.69

0.06

0.15

13.05

14.26

50.05

65.79

97.26

47.21

62.94

94.41

3.93393

5

22.62

21.92

5.88

13.82

13.96

5.71

0.08

0.19

13.39

13.89

51.44

67.61

99.96

48.52

64.69

97.03

4.04306

6

26.57

25.78

6.83

13.39

13.57

6.65

0.10

0.23

13.80

13.48

53.09

69.78

103.16

50.07

66.76

100.14

4.17256

7

30.26

29.40

7.69

12.92

13.14

7.49

0.11

0.26

14.26

13.03

54.97

72.26

106.82

51.85

69.13

103.69

4.32061

8

33.69

32.78

8.45

12.44

12.70

8.25

0.13

0.30

14.78

12.57

57.07

75.01

110.89

53.82

71.77

107.65

4.48537

9

36.87

35.92

9.13

11.95

12.24

8.93

0.15

0.34

15.34

12.10

59.36

78.02

115.34

55.98

74.64

111.96

4.66506

10

39.81

38.83

9.73

11.47

11.79

9.54

0.16

0.38

15.95

11.63

61.81

81.24

120.11

58.30

77.73

116.59

4.85804

11

42.51

41.52

10.26

11.00

11.34

10.07

0.18

0.42

16.59

11.17

64.42

84.67

125.17

60.75

81.00

121.51

5.06278

12

45.00

44.01

10.73

10.55

10.91

10.55

0.19

0.45

17.27

10.73

67.15

88.27

130.49

63.34

84.45

126.67

5.27792

13

47.29

46.30

11.14

10.11

10.49

10.96

0.21

0.49

17.98

10.30

70.01

92.02

136.03

66.03

88.04

132.05

5.50223

14

49.40

48.41

11.50

9.70

10.08

11.33

0.23

0.53

18.72

9.89

72.96

95.90

141.78

68.82

91.75

137.63

5.73463

15

51.34

50.37

11.82

9.30

9.70

11.66

0.24

0.57

19.48

9.50

76.01

99.91

147.70

71.69

95.59

143.38

5.97420

16

53.13

52.17

12.10

8.93

9.33

11.95

0.26

0.60

20.26

9.13

79.14

104.02

153.78

74.64

99.52

149.28

6.22008

17

54.78

53.84

12.35

8.58

8.98

12.21

0.27

0.64

21.06

8.78

82.34

108.23

160.00

77.66

103.55

155.32

6.47158

18

56.31

55.39

12.57

8.25

8.65

12.44

0.29

0.68

21.87

8.45

85.60

112.52

166.34

80.74

107.65

161.47

6.72805

19

57.72

56.82

12.76

7.94

8.34

12.64

0.31

0.72

22.70

8.14

88.92

116.88

172.79

83.87

111.82

167.73

6.98895

20

59.04

58.15

12.94

7.65

8.05

12.82

0.32

0.75

23.54

7.85

92.29

121.31

179.34

87.05

116.06

174.09

7.25380

21

60.26

59.39

13.10

7.38

7.77

12.99

0.34

0.79

24.40

7.57

95.71

125.80

185.98

90.27

120.36

180.53

7.52219

22

61.39

60.55

13.24

7.12

7.51

13.13

0.36

0.83

25.27

7.31

99.16

130.34

192.69

93.52

124.70

187.05

7.79374

23

62.45

61.62

13.36

6.88

7.26

13.27

0.37

0.87

26.14

7.07

102.66

134.93

199.47

96.82

129.09

193.64

8.06815

24

63.43

62.63

13.48

6.65

7.02

13.39

0.39

0.91

27.02

6.83

106.18

139.56

206.32

100.14

133.52

200.28

8.34512


Framing Square usage Example: 8:12 Pitch
(Rafter Length Per Ft = 14.42) (Hip Rafter Length Per Ft = 14.78)
SS Angle = Speed Square Angle
Saw Angle produces compound Speed Square Angle
 
Tongue (8.00) Blade (12.00) for Rafter Plumb Cut Angle (SS Angle 33.69)
Tongue (12.00) Blade (8.00) for Rafter Level Cut Angle (SS Angle 56.31)
 
Tongue (8.00) Blade (12.42) for Hip Rafter Plumb Cut Angle (SS Angle 32.78)
Tongue (12.42) Blade (8.00) for Hip Rafter Level Cut Angle (SS Angle 57.22)
 
Tongue (3.33) Blade (14.78) for Hip Side Cut Angle (SS Angle 12.70) (Saw Angle 75.00)
Tongue (2.14) Blade (14.78) for Hip Backing Angle (SS Angle 8.25)
 
Tongue (3.22) Blade (14.42) for Jack Rafter Side Cut Angle (SS Angle 12.57) (Saw Angle 75.00)
 
Tongue (2.14) Blade (14.42) for Purlin Rafter Plumb Cut Angle (SS Angle 8.45) (Saw Angle 8.25)
Tongue (3.22) Blade (14.42) for Purlin Rafter Cross Cut Angle (SS Angle 12.57)
 
Tongue (2.14) Blade (14.42) for Roof Sheathing Plumb Cut Angle (SS Angle 8.45) (Saw Angle 8.25)
Tongue (3.22) Blade (14.42) for Roof Sheathing Cross Cut Angle (SS Angle 12.57)
 
Tongue (8.00) Blade (12.00) for Miter Box Gable Mould Plumb Cut Angle (SS Angle 33.69)
Tongue (8.00) Blade (12.42) for Miter Box 2 Cord Polygon Gable Mould Hip Plumb Cut Angle (SS Angle 32.78)
Tongue (3.22) Blade (12.00) for Miter Box 2 Cord Polygon Gable Mould Hip Cross Cut Angle (SS Angle 15.00) (Saw Angle 15.00)
 
Tongue (2.14) Blade (14.42) for Frieze Block Plumb Cut Angle (SS Angle 8.45)
Tongue (3.22) Blade (14.42) for Frieze Block Cross Cut Angle (SS Angle 12.57) (Saw Angle 12.44)
 
Tongue (2.14) Blade (14.42) for Square Cut Fascia Plumb Cut Angle (SS Angle 8.45)
Tongue (3.22) Blade (14.42) for Square Cut Fascia Cross Cut Angle (SS Angle 12.57) (Saw Angle 12.44)
 
Tongue (0.38) Blade (3.22) for Hip Rafter Square Cut Fascia Plumb Cut Angle (SS Angle 1.83)
Tongue (3.22) Blade (14.42) for Hip Rafter Square Cut Fascia Cross Cut Angle (SS Angle 12.57) (Saw Bevel Angle 12.44)