How to Replace a Patio Door
A new, efficient patio door stops drafts, saves energy and eliminates leaks. Learn how to do your own sliding glass door replacement.
A full day
Intermediate
$101–250
Introduction
If you've been putting up with a drafty patio door that sticks, fogs up or leaks during a heavy rain, it's time to consider a new, energy-efficient replacement. While a high-quality door isn't cheap, it'll cut down on drafts, require almost no maintenance, glide smoothly and latch securely. Best of all, you'll save $300-plus if you install a sliding glass door replacement yourself.Tools Required
- 4 ft. level
- 4-in-1 screwdriver
- Clamps
- Drill/driver - cordless
- Finish nail gun
- Hammer
- Miter saw
- Pry bar
- Reciprocating saw
- Table saw
- Tape measure
- Utility knife
Materials Required
- Flexible flashing
- New sliding door
- PVC cement
- PVC sill pan
- Silicone caulk
- Wood shims
Project step-by-step (14)
Step 1
Measure the Opening Before You Buy
- Pry the interior trim free.
- Chip away drywall to expose framing.
- Pull off the interior trim around the old door and measure the “rough opening” width (distance between studs) and height (floor to beam).
- Pro tip: Make sure you measure to the framing right next to the old door jamb. You may have to cut away overhanging drywall to get at it.
- To check the height, make sure you’re measuring to the subfloor.
- That is, measure to the wood or concrete that the doorsill actually rests on and not a secondary layer of particleboard or plywood (underlayment).
- Select a new sliding glass door that fits your rough opening.
- Pro tip: Once you get your door home, you’ll save a lot of time if you finish any exposed wood surfaces on the door before beginning the installation.
Step 2
Remove Old Sliding Glass Door From Frame
- Latch the door, then unscrew and remove the inside head stop.
- Unlatch the door, tip the top of the sliding panel inward and lift it free of the track.