12

The offset and return elbows may be attached together, or a section or sections of chimney may be used between, but do not exceed 20' in total length between elbows. If sections of pipe exceed 10' between elbows, a chimney stabi- lizer must be used at the midpoint (Figure 36 ). The stabilizer support straps must be attached under tension (in shear) to structural framing members above. When two sets of elbows are used, the maximum combined length of chim- ney used between elbows cannot exceed 20' (Figure 37 ). Example: If C1 = 10' then C2 cannot exceed 10'.

If an offset exceeds 6' in length, each chimney joint beyond the first 6' of offset to the return elbow, must be secured by a No. 8 x 1/2" sheet metal screw located at the underside of the joint (Figure 38 ).

A 1/8" diameter hole must be drilled in the chimney joint using a 1/8" diameter drill. Hole should be drilled in center of joint overlap (Figure 39 ). Be sure to drill only through the outer chimney casting. Do not puncture the inner flue.

Maximum offset of chimney system is 30° . Two offsets must not be assembled to form a 60° offset. However, two sets of offset and return elbows may be used on a single flue system, provided the total height of the system exceeds 25'.

Return elbow support straps must be securely attached under tension (in shear) to structural framing members above. Do not substitute a FTF8-30 offset elbow in place of a FTF8-E30 return elbow.

OFFSET CALCULATIONS

Step 1. Use Offset Chart to determine amount of horizontal offset (A) and height (B) for vari- ous chimney section assemblies.

Step 2. Use “Height of Chimney Only” column in The Vertical Elevation Chart to determine combinations of chimney used above return elbow to achieve desired heights. Reference Components Effective Height Chart in vertical elevation chart section.

Step 3. Use Elevation Chart as job estimator only. Add necessary firestop spacers and stabi- lizers as required. Firestop spacers must be used as shown in Figures 22 and 23 and stabi- lizers as shown in Figure 28.

FTF8 VERTICAL ELEVATION CHART

 

Height Of

 

 

Number Of FTF8

 

 

Height Of

 

 

Number Of FTF8

Chimney Only

 

Chimney Lengths

 

 

Chimney Only

 

Chimney Lengths

Inches

Feet/Inches

12"

18"

36"

48"

 

Inches

Feet/Inches

12"

18"

36"

48"

11

 

0

11

 

1

0

0

0

 

386

¹⁄₂

32

2

¹⁄₂

0

1

0

8

17

 

1

5

 

0

1

0

0

 

390

³⁄₄

32

6

³⁄₄

2

0

0

8

21

¹⁄₄

1

9

¹⁄₄

2

0

0

0

 

396

³⁄₄

33

0

³⁄₄

1

1

0

8

27

¹⁄₄

2

3

¹⁄₄

1

1

0

0

 

404

¹⁄₂

33

8

¹⁄₂

0

0

1

8

35

 

2

11

 

0

0

1

0

 

414

³⁄₄

34

6

³⁄₄

1

0

1

8

47

 

3

11

 

0

0

0

1

 

416

¹⁄₂

34

8

¹⁄₂

0

0

0

9

51

¹⁄₄

4

3

¹⁄₄

0

1

1

0

 

420

³⁄₄

35

0

³⁄₄

0

1

1

8

57

¹⁄₄

4

9

¹⁄₄

1

0

0

1

 

426

³⁄₄

35

6

³⁄₄

1

0

0

9

63

¹⁄₄

5

3

¹⁄₄

0

1

0

1

 

432

³⁄₄

36

0

³⁄₄

0

1

0

9

67

¹⁄₄

5

7

¹⁄₄

2

0

0

1

 

437

 

36

5

 

2

0

0

9

73

¹⁄₄

6

1

¹⁄₄

1

1

0

1

 

443

 

36

11

 

1

1

0

9

81

¹⁄₄

6

9

¹⁄₄

0

0

1

1

 

450

³⁄₄

37

6

³⁄₄

0

0

1

9

93

¹⁄₄

7

9

¹⁄₄

0

0

0

2

 

461

 

38

5

 

1

0

1

9

97

¹⁄₄

8

1

¹⁄₄

0

1

1

1

 

462

³⁄₄

38

6

³⁄₄

0

0

0

10

102

¹⁄₂

8

6

¹⁄₂

1

0

0

2

 

466

³⁄₄

38

10

³⁄₄

0

1

1

9

109

¹⁄₄

9

1

¹⁄₄

0

1

0

2

 

472

 

³⁄₄

39

4³⁄₄

1

0

0

10

113

¹⁄₂

9

5

¹⁄₂

2

0

0

2

 

478

³⁄₄

39

10

³⁄₄

0

1

0

10

119

¹⁄₂

9

11

¹⁄₂

1

1

0

2

 

483

 

40

3

 

2

0

0

10

127

¹⁄₄

10

7

¹⁄₄

0

0

1

2

 

489

 

40

9

 

1

1

0

10

137

¹⁄₂

11

5

¹⁄₂

1

0

1

2

 

496

³⁄₄

41

4

³⁄₄

0

0

1

10

139

¹⁄₄

11

7

¹⁄₄

0

0

0

3

 

507

 

42

3

 

1

0

1

10

143

¹⁄₂

11

11

¹⁄₂

0

1

1

2

 

508

³⁄₄

42

4

³⁄₄

0

0

0

11

149

¹⁄₂

12

5

¹⁄₂

1

0

0

3

 

513

 

42

9

 

0

1

1

10

155

¹⁄₂

12

11

¹⁄₂

0

1

0

3

 

519

 

43

3

 

1

0

0

11

159

³⁄₄

13

3

³⁄₄

2

0

0

3

 

525

 

43

9

 

0

1

0

11

165

³⁄₄

13

9

³⁄₄

1

1

0

3

 

529

¹⁄₄

44

1

¹⁄₄

2

0

0

11

173

¹⁄₂

14

5

¹⁄₂

0

0

1

3

 

535

¹⁄₄

44

7

¹⁄₄

1

1

0

11

183

³⁄₄

15

3

³⁄₄

1

0

1

3

 

543

 

45

3

 

0

0

1

11

185

¹⁄₂

15

5

¹⁄₂

0

0

0

4

 

553

¹⁄₄

46

1

¹⁄₄

1

0

1

11

189

³⁄₄

15

9

³⁄₄

0

1

1

3

 

555

 

46

3

 

0

0

0

12

195

³⁄₄

16

3

³⁄₄

1

0

0

4

 

559

¹⁄₄

46

7

¹⁄₄

0

1

1

11

201

³⁄₄

16

9

³⁄₄

0

1

0

4

 

565

¹⁄₄

47

1

¹⁄₄

1

0

0

12

206

 

17

2

 

2

0

0

4

 

571

¹⁄₄

47

5

¹⁄₄

0

1

0

12

212

 

17

8

 

1

1

0

4

 

575

¹⁄₂

47

11

¹⁄₂

2

0

0

12

219

³⁄₄

18

3

³⁄₄

0

0

1

4

 

581

¹⁄₂

48

5

¹⁄₂

1

1

0

12

230

 

19

2

 

1

0

1

4

 

589

¹⁄₄

49

1

¹⁄₄

0

0

1

12

231

³⁄₄

19

3

³⁄₄

0

0

0

5

 

599

¹⁄₂

49

11

¹⁄₂

1

0

1

12

236

 

19

8

 

0

1

1

4

 

601

¹⁄₄

50

1

¹⁄₄

0

0

0

13

242

 

20

2

 

1

0

0

5

 

605

¹⁄₂

50

5

¹⁄₂

0

1

1

12

248

 

20

8

 

0

1

0

5

 

611

¹⁄₂

51

11

¹⁄₂

1

0

0

13

252

 

21

0

 

2

0

0

5

 

617

¹⁄₂

51

5

¹⁄₂

0

1

0

13

258

 

21

6

 

1

1

0

5

 

621

¹⁄₂

51

9

¹⁄₂

2

0

0

13

266

 

22

2

 

0

0

1

5

 

627

¹⁄₂

52

3

¹⁄₂

1

1

0

13

276

 

23

0

 

1

0

1

5

 

635

¹⁄₂

52

11

¹⁄₂

0

0

1

13

278

 

23

2

 

0

0

0

6

 

645

¹⁄₂

53

9

¹⁄₂

1

0

1

13

282

 

23

6

 

0

1

1

5

 

647

¹⁄₂

53

11

¹⁄₂

0

0

0

14

288

 

24

0

 

1

0

0

6

 

651

¹⁄₂

54

3

¹⁄₂

0

1

1

13

294

³⁄₄

24

6

³⁄₄

0

1

0

6

 

657

¹⁄₂

54

9

¹⁄₂

1

0

0

14

298

¹⁄₄

24

10

¹⁄₄

2

0

0

6

 

663

¹⁄₂

55

3

¹⁄₂

0

1

0

14

304

¹⁄₄

25

4

¹⁄₄

1

1

0

6

 

667

³⁄₄

55

7

³⁄₄

2

0

0

14

312

 

26

0

 

0

0

1

6

 

673

³⁄₄

56

1

³⁄₄

1

1

0

14

322

¹⁄₄

26

10

¹⁄₄

1

0

1

6

 

681

¹⁄₂

56

9

¹⁄₂

0

0

1

14

324

 

27

0

 

0

0

0

7

 

691

³⁄₄

57

7

³⁄₄

1

0

1

14

328

¹⁄₄

27

4

¹⁄₄

0

1

1

6

 

693

¹⁄₂

57

9

¹⁄₂

0

0

0

15

334

¹⁄₄

27

10

¹⁄₄

1

0

0

7

 

697

³⁄₄

58

1

³⁄₄

0

1

1

14

340

¹⁄₄

28

4

¹⁄₄

0

1

0

7

 

703

³⁄₄

58

7

³⁄₄

1

0

0

15

344

¹⁄₂

28

8

¹⁄₂

2

0

0

7

 

709

³⁄₄

59

1

³⁄₄

0

1

0

15

350

¹⁄₂

29

2

¹⁄₂

1

1

0

7

 

714

 

59

6

 

2

0

0

15

358

¹⁄₄

29

10

¹⁄₄

0

0

1

7

 

720

 

60

0

 

1

1

0

15

368

¹⁄₂

30

8

¹⁄₂

1

0

1

7

 

727

³⁄₄

60

7

³⁄₄

0

0

1

15

370

¹⁄₄

30

10

¹⁄₄

0

0

0

8

 

738

 

61

6

 

1

0

1

15

374

¹⁄₂

31

2

¹⁄₂

0

1

1

7

 

739

³⁄₄

61

7

³⁄₄

0

0

0

16

380

¹⁄₂

31

8

¹⁄₂

1

0

0

8

 

744

 

62

0

 

0

1

1

15

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Page 12
Image 12
Superior BCI-36, BR-36-2, BC-36 FTF8 Vertical Elevation Chart, Offset Calculations, Number Of FTF8, Chimney Lengths, Inches