Notice I didn’t say you would install it “on the outside of the garage.” I said you would “embed it in the wall.” You typically have to cut a hole into the wall. Depends on the thickness of the wall as to what goes inside the wall and what can go on the other side of it.
Demo board: A piece of a door just big enough to hold the lock
If you’ve ever seen a lock on a demo board at Home Depot or in the trade show pictures, that’s basically what you’re going to start with for either approach.
Option 1: install the lock on a demo board, then attach the demo board to the outside of the house
If you’re OK with it being raised up off the side of the wall by enough space to hold the back part of the lock, you can just attach the whole thing to the exterior wall without cutting into the wall at all. You just have to figure how you’re going to secure it. I think most people in that case would put the whole demo board inside a locked case so you unlock the case and then use the keypad.
just remember that you will need to be able to change batteries from time to time.
Option 2: install the lock on a demo board, and put the demo board inside the wall with just the keypad showing on the exterior
If you actually embed it into the wall, then just the keypad part will be on the exterior, the deadbolt will be inside the wall, free to move but not locking anything, and you will have access from the other side of the wall to change the batteries.
Embedding it looks nicer and may be more convenient if you would otherwise need the lock in case, but it’s a much bigger construction project.
If you just want the exterior part of the lock to show and you want to put everything else inside the wall, then You’ll install the lock onto a demo board piece to hold everything in place, cut a hole in the wall from each side, put the demo board inside the wall so that the keypad is positioned the way you want it on the exterior wall.
You’ll want access from the interior side of the wall so that you’ll be able to change the batteries when needed.
It’s similar to installing a mailbox slot in the wall except that the interior width of the cut out will be bigger then the exterior piece to allow for the deadbolt. So you will probably place the demo board from the interior side (where you will make a bigger hole).
So again, pretty similar to installing a pet door. You may want to “tunnel” Frame inside the wall, again also just to hold everything in place.
Of course, it all depends on the material of the wall you want to put it into. If that wall is brick, That means Masonary saws and a lot of specialty equipment and you might want to have an experienced contractor do it. All of which is more cost and money.
So a lot comes down to whether you are OK with the aesthetics of just surface mounting the entire demo board, and whether that give you enough security in your neighborhood to keep people from stealing the lock itself.
Embedding is more secure and arguably looks nicer, but it’s way more work.