They've done the exact modification that you're proposing (placing it next to the door, rather than in the door) at my place of work.
What you're looking for is called an 'electronic strike'.
You cut out the area around the existing strike plate, and wire in the electronic strike. You'll need to feed it power, and a signal from whatever you have to grant access. (in our case, the card reader, plus a motion detector so it'll open from the inside automatically; you don't need the motion detector if you still have a functioning door handle from the inside)
A quick search online suggests that they run $100-500 (US$), but you'll probably want to contact the manufacturer of the card reader to ensure you get something that's compatible.
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As for 'best practice', much of it comes down to cost vs. what you're trying to protect.
The advantage of the electronic strike is that it can be hard-wired for power (no batteries to replace every few months), and you don't have to worry about cable bundles through the door or wireless signals (for auth & logging) that can be intercepted or interfered with.
If you're only protecting a single door (so don't have a centralized authentication server), don't need to log each person individually, and don't mind changing out batteries once in while, you might try looking at the locks they use for hotel room doors that replace out the existing handle + lock mechanism.
This looks to be like a schlange or kwikset lockset commonly found at Home Depot. You can easily re-cylinder this, but it isn't obvious how to get the lock off.
My solution was as follows:
- Rotate the lever to the vertical position. There will be two screws hidden under it.
- Remove them, and separate the lock into two halves.
- The lock-half has a cover on it. Remove it.
- There's a screw that holds the cylinder in.
You can also get a lock/lever combination, as well as new doorknobs -- in many cases you can re-use the existing deadbolt and striker latch and just change the visible hardware.
Best Answer
To my knowledge, you won't find any modern in-door deadbolts that can accommodate such a thin door. Even if you padded the width of your door around the installation point to reach the minimum needed, drilling the hole for the deadbolt will essentially remove a notch from your original door (deadbolts are commonly 1" thick). Your spacers will have to go all the way to the edge of the door to conceal the deadbolt.
A simpler solution would be to use a surface-mount deadbolt, which requires only that you drill a hole for the rim cylinder. You may have to add a spacer around the rim cylinder to get a flush fit, but it won't end up being the only thing concealing the lock mechanism from tampering. That link shows several types, including jimmy proof deadbolts and night latches.