I think I have a void in my wall cavity in my master bedroom. When it's cold outside I feel a draft in a certain area. That same area gets colder to the touch than other places on that same wall.
I have some plugs in the siding which tells me that previous owners blew in wall insulation. I'm not sure if it's cellulose or fiberglass, but I think it's yellow (saw some insulation in the walls when putting dishwasher in).
So what should I do in this situation? Can I just rent a machine and blow in more insulation? Is it likely to fill that void on the wall cavity? Or is spray foam a better choice in this situation?