What to do if windows do not close properly

What to do if your PVC windows do not close properly

Windows that won't close correctly are a common problem in apartments and houses. The causes range from dirty hardware and worn seals to a sash that has dropped or frame misalignment. Below is a practical guide to diagnosing the problem, simple fixes you can do yourself, preventive tips, and when to call a professional.

Quick check — 5 minutes

• Close the window and note the effort required and any unusual sounds.
• Inspect the gasket for cuts, deformation or hardening.
• Use a paper test: close the window on a sheet and try to pull it out. If it slides out easily — there is a draft.
• Check hinges and strike plates for rust, dirt, or protruding screws.

Common causes and solutions

1. Dirty or dry fittings

Dust and old grease impair movement.

• Clean visible hardware with a soft brush and cloth.
• Apply silicone lubricant or a window-specific spray to moving parts. Avoid machine oil that attracts dirt.

2. Sagging sash

Over time the sash can sag, causing it to hit the frame or miss the gasket.

• Adjustment screws on the hinges allow vertical and horizontal repositioning.
• Make small adjustments (quarter turns), then test the sash.
• If heavily sagged, contact an installer — heavy or large sashes can be difficult to realign alone.

3. Incorrect compression (seal pressure)

Too little compression causes drafts; too much makes closing difficult.

• Modern windows allow micro-adjustment of compression via cams or adjustable strike plates.
• Turning the cam or adjusting the strike plate will increase or decrease compression.

4. Worn or deformed gasket

The gasket loses elasticity and can flatten.

• Inspect the seal around the entire perimeter. Replace if cracked or flattened.
• Cleaning with warm soapy water and treating with a silicone spray can temporarily restore flexibility.

5. Frame or opening deformation

If the frame or opening is out of square, the sash may not close properly.

• This often requires removing trim and a professional assessment of frame geometry and possible reinstallation.

Step-by-step basic adjustment (DIY)

1. Remove decorative hinge covers if present.
2. Check for protruding screws or obstructions.
3. Clean and lubricate the hardware with silicone spray.
4. Use hex keys to adjust hinge screws for vertical and horizontal alignment.
5. Adjust compression cams or strike plate for proper seal.
6. Reinstall covers and test fully in closed, tilt and open positions.

Note: Avoid forcing adjustment screws without understanding their function — incorrect turns can damage the mechanism.

When to call a professional

• If problems persist after cleaning and basic adjustment.
• When the sash or frame is noticeably warped or heavily corroded.
• If the glass unit is cracked or hardware needs replacement.
• For full gasket replacement around the perimeter.

Tools and materials you may need

• Hex keys (commonly 4 mm and 5 mm).
• Phillips and flat screwdrivers.
• Silicone spray lubricant for windows.
• Soft brush and cloth.
• Replacement gasket if needed.

Preventive care

• Lubricate moving parts once a year.
• Check and clean seals twice a year.
• Avoid leaving the window in a semi-open tilt position for long periods.
• Ask the manufacturer for adjustment instructions when buying new windows.

Short FAQs

• Can I replace the gasket myself? Yes on many models, if you measure carefully and follow steps.
• Is it dangerous to adjust screws? It can be if you don’t know which screw does what — consult instructions or a pro.

Conclusion

Many closing problems can be solved by cleaning, lubrication, and careful adjustment. If in doubt, calling a specialist can save time and prevent damage to the mechanism.