How to Cut Into Existing Ductwork in a Basement

You can use an electric drill when working with basement ductwork.

You may need to cut into existing basement ductwork when making room additions or adding vents. Ductwork is typically constructed of aluminum, a material that is convenient to work with as long as you avoid bodily contact with sharp, cut edges. You'll need to use a few basic tools, such as an electric or cordless drill and tin snips, when cutting aluminum. Tin snips are easy to manipulate and use when cutting ductwork material.

Things You'll Need

• Felt-tip marker
• Measuring tape
• Stepping stool or small ladder (optional)
• Object being attached to ductwork
• Electric drill
• ½-inch drill bit
• Tin snips
• Gloves
• Safety glasses

Instructions

1. Locate the ductwork in the basement and determine where you will make the cuts. Make layout marks on the ductwork using a felt tip marker by either transferring the measurements from the object that you're attaching to the ductwork, or by tracing around the object while it's pressed firmly against the ductwork.

2. Put on a pair of safety glasses and heavy-duty work gloves. Make sure that your work area is accessible and clean of clutter. Use a stepping stool or small ladder for easier accessibility.

3. Attach a 1/2-inch drill bit to the drill chuck. Drill a hole through the ductwork within the lines of the cut out, or waste material.

4. Slip the tin snips' open nose through the drilled hole and start cutting along the layout lines. Remove the tin snips and drill additional holes into the ductwork as needed.

5. Vacuum any dust or debris from around the ductwork hole to prevent it from clogging the ducts in other areas.

Tips & Warnings

• If you're unsure about the layout or size of the hole, start out by making the hole slightly smaller in size.

• Before adding more ductwork or vents to an existing system, check to make sure that the current system will be able to handle the added stress. If a system is overloaded with vent openings, other rooms in the structure may suffer heating and cooling loss.

• Wear personal protection equipment, such as safety glasses and a heavy-duty pair of gloves to protect your hands from the aluminum ductwork's sharp edges.

References

• Family Handyman: How to Use Tin Snips to Cut Sheet Metal
• "Carpentry 4th Edition"; Leonard Koel; 2004