How To Shim Gapping Doors (DIY) | Family Handyman

Big gaps along the latch side of your interior doors can be annoying. They let in light while you’re trying to sleep or even an unwelcome draft. Fortunately, there’s an easy fix.

What causes gaps in doors?

The most likely reason for the gap is that they were probably prehung in their frames at the factory and installed as a unit. The installer should have adjusted the frame with shims to leave about a 1/8-in. gap along the latch side, about the thickness of two coins when hanging the doors. Sometimes the gap is far too wide.

What is a prehung door?

Prehung doors are a big timesaver because the door is already hung in the three-sided frame by three hinges, so that they’re less complicated to install compared to a slab door. They come in standard sizes to help streamline the process by eliminating the work of building and installing a separate frame. 

They are pretty much a full kit in one package. However, you will need to purchase and install a doorknob with it, choosing one to match the design and decor style in your home. You may also need to paint prehung doors.

How do you fix a the gap in a door?

To readjust the door frame, you have to remove the trim along the door’s latch side to get at the shims. This job can be a hassle, especially if you have painted trim. So try this trick first. Slip a 1/16-in.-thick cardboard shim strip behind each hinge (Photos with steps 1 and 2 below). This will widen the gap along the hinge side and narrow the gap along the latch side. Hopefully, this shim will be enough to make the latch solid.

How to hang interior doors

Here, we’re just making some adjustments to fix the gap in the door. You shouldn’t have to remove the door to do this. But if you do find yourself hanging a new door, be sure to use shims to correct for the gap when hanging it the first time. That will save you some work down the road.