How to Line Up a Wood Stove Pipe Offset

Pipe offsets shift ventilation around roof rafters and obstructions.

Wood stoves require ventilation pipes that carry ash and smoke outdoors. The pipes can extend through a wall but often extend through the ceiling and terminate above the roof. While stove ventilation pipes typically run straight up, obstructions such as a rafter can block their path. When this occurs, a pipe offset bends the pipe around the obstruction. Lining up the offset on the main pipe requires assembling the offset pieces and arranging them properly on the ventilation system.

Things You'll Need

• 90-degree duct elbow
• Foil tape
• Ladder
• Tape measure
• Straight rigid duct
• Tin snips
• Pencil
• Drywall knife
• Rotary hand tool
• Safety glasses
• Dust mask
• Pipe offset
• Offset bracket
• Screwdriver
• 1-inch nails
• Hammer

Instructions

1. Find the ventilation hole on the back of the wood stove and install a 90-degree elbow over it, securing it using foil tape.

2. Measure up to the ceiling using a tape measure and cut a straight piece of rigid metal duct to this size using tin snips.

3. Hold the metal duct up to the ceiling location and trace around it using a pencil. Don safety glasses and cut out the hole using a drywall saw or a rotary hand tool. Wear a dust mask and safety glasses when cutting through the ceiling.

4. Insert one end of the straight duct into the elbow attached to the wood stove and wrap the seam using more foil tape.

5. Peer up into the ceiling hole or, if possible, enter the attic space. Locate the obstruction, such as a rafter, that is in the the way of the duct.

6. Align the two pieces of the pipe offset so they form a slight S shape, and push the ends that face each other firmly together. Rotate the offset until the bottom pipe opening centers over the top of the duct and the curve angles away from the obstruction.

7. Push the offset into the bottom duct opening and wrap foil tape around it.

8. Wrap an offset bracket circle around the offset so that it rests in the curve of the pipe. Inset the bolt through the end of the circle and tighten it using a screwdriver. Raise the two metal hanging straps up to the nearest rafter or other wooden portion of the roof and nail them in place using 1-inch nails inserted through the predrilled holes.

9. Proceed with installing the roof vent and the remainder of the wood stove ventilation system.

References

• Northline Express: Planning Your Chimney Installation
• Selkirk: Wood Stove Chimney Installation Planner
• You Tube: Duratech 30 Degree Offset and Return 9466kit & 9666kit