If your window only opens partway and then suddenly stops, it can feel like something is broken.
In most cases, it’s not.
Many modern windows include a built-in safety feature called a night latch, and it’s often the reason your window won’t open fully.
The good news is this is an easy fix once you know what to look for.
⚡ TLDR: Quick Fix for a Window That Won’t Fully Open
- Check for night latches on both sides of the window
- Press both latches inward at the same time
- Continue opening the window past the stopping point
Watch the 30-Second Fix
If you’d rather see exactly how it works, watch the quick video here:
What Is a Night Latch?
A night latch, sometimes called a vent stop latch, is a small safety feature built into many windows.
It allows the window to open slightly for ventilation while still preventing it from opening fully. This can be useful for:
- Added security
- Letting fresh air in safely
- Limiting how far the window can open
If the latch is engaged, the window will stop at a certain point.
Why Your Window Stops Halfway
If your window slides or lifts but won’t go all the way, the night latch is likely engaged.
This is normal behavior.
The latch is designed to catch and stop the window unless it’s manually released.
Step-by-Step: How to Open the Window Fully
Step 1: Locate the Night Latches/ Vent Stop Latches
Look along both sides of the window sash.
You’ll usually find small tabs or clips that sit slightly inside the frame.
Step 2: Press Both Latches Inward
Using your thumbs, gently press both latch tabs inward at the same time.
It’s important to press both sides together.
Step 3: Continue Opening the Window
While holding the latches in, slide or lift the window past the stopping point.
Once it clears the latch, the window should open normally.
What If It Still Won’t Open?
If the window still feels stuck:
- Make sure both latches are fully pressed in
- Try applying even pressure on both sides
- Check for dirt or debris along the track
If the issue continues, there may be another cause such as alignment or track resistance.
Final Thoughts
A window that won’t open fully is usually not a defect. It’s often just a safety feature doing its job. Once you know how the night latch works, it becomes a quick and simple fix.
If something still doesn’t feel right, it’s always best to take a closer look before forcing the window.
Need help with your replacement windows? Contact Brookstone Windows & Doors for expert support and a free consultation.
👉 For more maintenance tips, visit brookstone.ca/resources