Insulation Behind the Trim

• 1). Remove the door trim, both on the inside and outside, using a small crowbar and hammer. Some trim is held in place with screws, so use a cordless drill and screw bit to remove the screws first, then pry off the trim pieces.
  
  
• 2). Inspect the area between the patio door frame and wall studs to see what kind of insulation is in place. Some doors will have no insulation at all. Others may have the "yellow" fiberglass insulation you sometimes see used around pipes. Other insulation may just be worn out or broken in places.
  
  
• 3). Pull out all the old insulation. Cut away the insulation with a utility knife. Some insulation is toxic, so place all old insulation in garbage bags and dispose of properly.
  
  
• 4). Press new backer-rod insulation into place. Backer-rod insulation is round and comes in a roll. Press in place as you unroll it, working your way around the door frame. Do this on the outside of the door.
  
  
• 5). Spray in non-expanding foam to fill in any small spaces. Let dry for a couple of hours.
  
  
• 6). Replace the trim again, using the old screws or new stainless-steel screws.
  
  

Insulating Sliding Door Glass

• 1). Measure the height and width of the door glass.
  
  
• 2). Cut the film in the kit 1 inch bigger than needed, all the way around the door, using the utility knife.
  
  
• 3). Apply double-stick tape to the inside edge of the door glass.
  
  
• 4). Press the window film onto the door glass, starting at the bottom and working your way up. Press the edges onto the double-stick tape to hold the film in place.
  
  
• 5). Heat the film, using a blow-dryer, until it shrinks in place.