How To Install Sliding Glass Door | Easily Remove Old Door!

Wondering how to install sliding glass doors? Check out this project where I show you the easiest way to knock out old sliding glass doors!

This week I am finally tackling the issue these double doors have frustrated me with since buying this house.

The function of double doors is wonderful but they are notorious for causing problems for me. The reliability of this door opening or staying closed is all dependent on how much rain we’ve had. Meaning, sometimes it will open easily. Other times it won’t open at all.

I finally had my fill and I’m replacing it with a more reliable door, which is the classic sliding door.

In case you have the same issue, let me show you the process and shorten your learning curve, as it’s really quite simple and an easy fix that will save a ton of headache.

The first thing I needed to do was to remove the outside trim. I used a box blade to score a line on the inside and outside of the trim to cut through the caulking joints.

Next I used a variety of prying tools to pry up the trim. On each side, I was attempting to remove the trim in a single piece because the trim will have to be reinstalled after the new doors go in. But if it’s easier to break it in pieces then alternatively you can just put down a new board in the end.

The main thing is to not chip the siding as that’s a bummer and isn’t an easy fix.

Okay next step is to remove the doors. This is simple enough now without the trim. I just had to take out all of the screws holding the hinges to the doorway.

I just set mine aside but I recommend donating your old doors to habitat restore so that they don’t have to go to a dump. Or you can always up cycle them to another structure you have like a shed.

Next I moved to the inside and repeated the scoring action on the inside trim. My goal is to try and leave the inside trim in place because looking at my doors i don’t think I’ll have to remove it. But if you have to remove yours it’s the same process as the outside.

Next I looked for screws. sometimes installers hide screw under the weather stripping which is a great install tip actually. But if you were taking a door out, remove the stripping to see if there are any. I only had one. Since I wasn’t able to get it out, I just cut it off with the trim joint cut.

I next cut a line with my putty knife through the spray foam along the outside. In my case, I only have it along the top. But if you had a better builder, you might have it around all three.

Finally I used my same prying tools to slightly pry up without removing the inside trim.

The trim nails attaching the trim to the door are the last things holding the door in place. I used a multi-tool to cut through the nails then a pry bar to work the door completely out and hauled away.

Perfect. Now I have a great big opening to work with.

Now I do recommend looking at the weather before tackling this project as you will have your whole house open for at least an hour, if not a few.

Once I removed my door, i noticed that my builder didn’t do any flashing around the perimeter I do have a large overhang. But since i’m down to bare, I went ahead and applied the correct protection.

I started by applying a strip of flexible flashing tape to the bottom lip, then folding the excess up and over the threshold.

Next I came back with door wrap that went from the corner to corner, only peeling back a little bit of paper backing at a time and applying a good amount of pressure as I went.

Once the entire piece is laid down, I came back with a roller to apply more firm pressure and work out any creases.

Now corners are the tricky part. This huge roll of flex flashing is $18 but a roll of this special flexible wrap made for corners is closer to $180.

That’s because instead of making choice cuts in order to get it to form around an inside corner, you literally just stretch it down and out to fit. It’s magic and worth the money. However, a tip here is to use the cheaper stuff on the long bottom stretch of the doorway than the expensive stuff just on the corners.

Okay, and now continue with flashing. Working upwards, I repeated the process to flash the sides going from the inside corner to inside corner.

Now bring in the door.

First thing to do is to apply a continuous bead of caulking around the back side of the nail flange, just right inside the screw holes. I did this on the left top and right but not the bottom. This is so that if water does find a way in it has a way to get out.

I’m using Dap’s Dynaflex 230 here. This is a premium interior or exterior sealant that is 100 waterproof. The sealant combines durability adhesion and flexibility plus cure sealant is mold and mildew resistant.

With that applied, you just need to find a strong friend and set the door in place. We aim to get the bottom end first then tilt the top of the door in.

Now the door can be attached with a few screws all along the nail flange. I first made sure the door was level and it was. However if it wasn’t, then I would have used shims to make it so.

Next, I plumbed the door. And it’s actually just plumbing the side of the frame as it’s pretty flexible.

I held up a level as a straight edge reference and made sure that the frame was touching everywhere along the line before screwing it down.

The next step is adding back trim. These doors aren’t as deep as the french doors so the inside this left a blank space. I simply put in some trim to fill it in after popping it in place. I reattached the inside trim to it first then I came back and attached the fill trim to the header.

I repeated that on both the left and right and bottom now to make it go away and look seamless. I caulked all of the seams and i’m using Dap’s Alex Fast Dry here. This stuff is ready to paint in 20 minutes so it’s great for projects where you don’t want a lot of downtime.

Next I move to the outside and button that side up since I broke most of my trim boards on the tear down, I just reinstalled new ones. this is simple enough.

After getting them installed then I caulked all of the seams. Then also applied some wood filler. I used Dap’s Premium Wood Filler that will be very durable over time, regardless if it’s inside or outside. This isn’t so pressing on the outside but it does really clean up the inside trim so that once you paint everything blends together and looks wonderful

Know that there are adjustments on the bottom of the door. You can turn the bottom bolt clockwise to raise the door up which pushes down the wheels. So if your door is difficult to open you can make adjustments here.

You can also open the door just slightly to quickly check how straight it’s sitting in the bottom of the track.

I really hope that if you have a sliding door on your to-do list that this shortens your learning curve and kind of prepares you for what you can expect from the project. I personally think the effort was 100 worth it. I love these doors.

I’ll see you on whatever i’m working on next!

Things I Used In This How To Install Sliding Glass Door Project:

• ISOtunes Ear Protection
• Flashing Tape
• Door Wrap
• Stretch Tape
• DAP Dynaflex 230 Sealant
• DAP Alex Fast Dry Caulk
• DAP Premium Wood Filler

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