Hold a tape measure to the edge of the door and record its thickness.
Measure for sliding door.
If the doorway has moldings measure from outside edge to outside edge to determine the proper door width add about 4 to 6 inches to your measurement.
Custom built sliding glass doors meet and or exceed these measurements.
Ideally the door will cover 2 to 3 inches beyond the opening on each side.
How to measure for replacement sliding glass patio doors.
These numbers should be close to the same but it can be helpful to know both of them.
Measure from the top of the track at one end of the door down to the threshold on the ground with a tape measure.
For the height measure from the top of the bottom track into the top u channel see the diagrams below.
Go to your sliding glass door and take a measurement from the wall left to right of the door to the wall it is installed in.
Then you will want to measure the height of the doors as well again do three measurements one from top to bottom on the left one in the middle and one on the right.
If your sliding screen doors are missing determine width by measuring from inside of side jamb to center of stile on opposite side just short of where the stationary glass begins.
Be careful not to damage it.
Write down the measurement.
Pull out any.
Be sure to capture both width and height measurements.
Cut away all the old silicone and paint attached to the door.
Do this across the bottom middle and top.
Write down the measurement.
Measure this edge on the door frame known as the jamb as well.
The most common thickness is 1 75 inches 4 4 cm.
To measure the height of a sliding patio door extend your tape measure vertically.
The average widths for three panel doors are nine feet and twelve feet.
Insert a utility knife around the door frame and break the silicone seal.
Measure vertically the same way from where the header meets the rest of the home to where the bottom sill ends.
Move halfway down the opening and measure again.
Remove the slider door trim with a crowbar.
Using a tape measure begin at the left edge of the opening and measure straight across to the right edge.