Doors – How to install modern locksets on these interior doors


I've recently bought my first house which I'm very excited about, got into the decorating phase and decided to replace the door handles – some of which were damaged – with nice new ones. Being a definite rookie when it comes to DIY, I was pretty much unaware of the problem I'm having was even a thing, so I apologise if I've made mistake 101 in this situation.

The problem I have is that the old hole that has been cut into the door through which the old door handle fitted is too near the edge of the door for the new mechanisms, which basically means the old mechanism was 4.5cm deep, and the new handles are (approx) 6cm deep. I've since been told that the barrel for a door knob rather than a door handle needs to be longer so that you don't hit your fingers when opening them.

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I am primarily looking for advice on the best way to solve this, and if there is anything I definitely shouldn't do.

The suggestions I have received from friends and family so far have been options between

  • Use the old latch mechanism – however some of them are damaged, and
    the bathroom doors had a secondary locking mechanism, so these doors have 2
  • Drill further into the existing hole as deep as this one needs
    to go (parallel to the door), fill the existing hole (perpendicular to the door), and then drill into it where the new hole needs to go as normal

    • or alternatively do not fill in the perpendicular hole, and use the door knob itself to cover where the old hole was
  • Completely fill this hole in, and start from a new position – I
    hadn't even realised since just now that the hole is not central to
    the middle section of the door

Personally my option was to fill in the perpendicular holes with some 1" wood, and effectively start from there.

Best Answer

You're going to have to drill a larger hole for the new handles, which should completely encompass the old hole.

Head on down to your local hardware store (or cruse the internet), and look for a door handle installation jig like this Irwin® Door Lock Installation Kit

Irwin® Door Lock Installation Kit
Example only, these jigs are available from many different manufacturers

It comes with the proper size hole saws to set up a door for modern locksets, and makes alignment of the holes quick and easy. Simply attach the jig where you want it, and drill the holes with the supplied hole saws.