- 1). Determine how much damage you are willing to face as a result of insulating. In order to insulate in between the wall joists on an exterior wall, the drywall will have to either be removed for batt-type insulation, or small holes will need to be cut into the drywall for blown-in insulation. These holes can be patched whereas with batt insulation you are looking at replacing larger sections of the wall.
- 2). Prepare the area. Lay down drop cloths underneath the wall. Tape them down to the floor to keep them from shifting. Any furniture in the room should be removed or covered. Put on safety glasses, gloves and a long-sleeved shirt to protect your skin.
- 3). Locate the wall studs with a stud finder. This will help you make your cuts. Mark the location of the studs with a pencil.
- 4). Remove the drywall. If you are using batt-type insulation, cut into the drywall in between the studs with a utility knife. Cut away the panel. Pull out any remaining nails or remove the screws. For blown-in insulation, make a small square hole at the bottom of the wall in between the studs.
- 5). Roll out batt-type insulation, measure it for the area where you will be installing it then cut it with the utility knife. Press the insulation into the hole and nail it in place. For blown-in insulation, insert the end of the nozzle into the small hole you created. Aim the nozzle upward and fill the area with insulation.
- 6). Patch over the area. Replace any missing drywall panels with new panels. Tape the seams and apply joint compound over them with a taping knife. For small holes, use a wall patch kit or make your own patches out of small pieces of drywall. Follow the same procedure to tape and mud the patch. Let it dry and sand it smooth for finishing.
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