OFFSET CALCULATIONS
Step 1. Use Offset Chart to determine amount of horizontal offset (A) and height (B) for various 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 sta- bilizers as required. Firestop spacers must be used as shown in Figures 21 and 22 and stabilizers as shown in Figure 27.
A1
A2
C2
B2
A1
B1
C1
FTF10 Chimney
Figure 38
6'
No
| 8m | ) | |
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(1 |
| Required | |
Screws | for | First | |
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Joints |
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| 4' |
| in |
| Offset |
6' |
| of |
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Joints
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| ) |
| at |
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| 2m | Required | Past | 6' | |
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(1 |
| Joint |
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Screws |
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| Every |
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No. 8 x ¹⁄₂" SMS
12
20' Max.
(6m)Stabilizer
B1
10' Max.
(3m)
Figure 36
A2
C2
B2
A1
B1
C1
Figure 37
NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.
Underside of Chimney
Figure 39
Return Elbow
FTF10 Chimney
Section (s)
A 
B
Offset Elbow 
65 ¹⁄₄"
(1657mm)
* Part of Offset/Return Package, Model
Figure 40
