How to Insulate a Wall Without Removing Paneling

Determine if it would be easier to fill the wall cavities from the interior or the exterior of your home. The process will require cutting into the wall between two studs. If done from the outside, you’ll need to remove a panel of siding to access the wall and then plug the hole after filling it, a simpler option that requires less repair work. If done from the inside, you’ll need to patch the drywall on each hole then repaint the patched area. Only go through the interior if the exterior of your home is covered in brick.

Remove a single length of siding panel from your home to access the wall beneath. Choose an easily accessible panel at about waist level. Different panel types have different methods of removal. Consult with your panel manufacturer for instructions on how to remove a panel. For windows, take a panel from both under and over the window to access the two sections of the wall cavity cut in half by the window placement.

Attach a 2-inch hole saw to a drill. Use the hole saw to cut through the sheathing of the wall between every two frame studs along its length. You can locate the studs by running a stud finder over the walls. The studs are typically located 16 inches apart but may be 24 inches apart on some homes. Place the hole in the center of the cavity between every two studs.

Slip the hose of a blower machine through the drilled hole and into the wall cavity pointed upward. Raise the hose until it’s about 2 to 3 inches from the top of the cavity.

Trigger the blower to shoot the insulation into the wall cavity. Pull the hose free slowly as it begins to push outward due to pressure from the insulation. After filling the top of the cavity, reinsert the hose downward and repeat the process for the bottom of the cavity. Pull the hose from the cavity as it fills.

Mount a 2-inch wall plug into the hole and tap it into place with a rubber mallet.

Repeat the filling process for all of the other cavity spaces. Place two holes, one above and one below window locations, to fill both halves of the cavity.

Replace the piece of siding by following the siding manufacturer’s instructions for placement.

Use the same process to fill the wall cavity from the interior, only drill through the drywall and then patch the drywall with a drywall patching kit. Paint the patched drywall area with a paint that’s the same color as the surrounding walls.