How to Cut Out Home Duct Work
- 1). Sharpen the knife with the sharpening stone. Keep the sharpening stone with you as you cut out the Fiberglas duct to put a new edge on the blade as needed.
- 2). Put on your particulate respirator, open the tape measure 24 inches and lay it on the ductwork. Make sure that the end of the tape measure is resting against the face of the HVAC unit.
- 3). Slide the cutting edge of the knife into the duct at the 12-inch mark of the tape measure that you placed on the duct.
- 4). Remove the tape measure from the top of the ductwork and cut around the perimeter of the ductwork with the knife.
- 5). Measure out 4 feet from the previous cut, and make another cut around the ductwork. Remove the duct piece from the duct line, and stand the duct on edge.
- 6). Slide the knife down each corner of the ductwork you removed to make four flat pieces of duct board. Stack the duct board in an area that is out of the way.
- 7). Free the ductwork from the hangers by cutting the hanger strap with aviation snips. Make the cut 2 inches above the top of the ductwork. Bend the end of the hanger strap attached to the joists to avoid cuts caused by the strap's raw end.
- 8). Continue to cut and remove the duct board as described in the previous steps, removing the hangers as you go, until you reach a branch line tap connected to the air distribution, known as a register.
- 9). Cut the flex free from the branch line tap with the aviation snips and hit the top of the tap with a hammer to crush the tap. Pull the crushed tap from the ductwork and continue removing the duct line.
- 10
Insert the Phillips screw tip into the chuck of the drill motor after you have the duct line removed. - 11
Remove the screws that hold the hanger strap to the wood rafters with the drill motor and Phillips tip. - 12
Exchange the Phillips tip with the 5/16th-inch hex head adapter, and remove the self-tapping screws that connect the duct board to the face of the HVAC unit. - 13
Dispose of the Fiberglas duct board and recycle the metal hanger strap and branch line taps.
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