How to Prevent a Double-Hung Window From Opening
- 1). Measure the thickness of each sash frame, then add these two figures together. You don't want to drill all the way through both sashes, just halfway through the second one. So divide this figure by ¾.
- 2). Apply a small tape mark to the drill bit, so you can see when you have drilled ¾ of the way through the sashes.
- 3). Drill a hole through the top right corner of the bottom sash frame. The hole should penetrate about halfway into, but not through, the second sash. The hole diameter should be the same as the diameter of the steel pin.
- 4). Thread the steel pin through the hole to secure the two sashes together.
- 5). Repeat steps 3 and 4 to secure the top left-hand corner of the bottom sash.
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