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Frequently Asked Questions

Can't find the answer you're looking for? Please get in touch with the team on 0800 716509.


Why doesn't my window open or close properly?

Possibly the friction stays (hinges) have become worn or have broken. The friction stay (hinges) are located either side of the actual window.

How do I restrict my window from fully opening?

We would recommend fitting a restrictor stay that allows the window to only open to a required opening distance. As a fire safety precaution the restrictor stay can be overridden at any time.

My window handle turns but the window will not open-can it be fixed?

This is the mechanism inside the window called an Espag lock that has broken and needs to be replaced.


Why is my front door difficult to close?

The likelihood is that the door has dropped. We can adjust your door and keeps if necessary. Sometimes extreme changes in the weather can cause the materials in the door to expand and contract, making the door difficult to shut properly.

Why does my patio door not slide properly?

Probably the rollers have worn out, and possibly the track may also be damaged. This can be confirmed by a site visit.

I've been burgled – do I need to change my front door keys?

Yes you do. If you have a UPVC door, we would fit a new cylinder lock. If you have a timber door, we would completely replace the mortise lock fitted to the front door.



For frequently asked questions about condensation please read the attached brochure – click here.

The inside of the glass unit is misty and the window has condensation inside the window. Can this be repaired?

Yes, it is possible to repair a sealed unit, but we would recommend a professional Glazier to carry out the work. Cohens Glass can repair, replace and maintain double glazing units to the highest standards without causing damage to the frame.

What is a sealed unit?

Double glazed windows are made up of 2 panes of glass, separated by a spacer bar to create a gap. This gap is filled with a gas called argon which is a poor conductor of heat, therefore creating a barrier between the warm room and the cold temperature outside. The unit is sealed around the edges to make it airtight. A sealed unit is sometimes referred to as a DGU (double glazed

I have a lead light window pattern on my sealed unit and the outer clear glass panel has broken. Can you match the same pattern?

Yes, the lead pattern can be reproduced onto the new piece of glass so that it matches your previous lead light design.

What causes double glazed units to fail?

Changes in temperature can cause the materials in the glazed unit to expand and contract over time, which can result in gas or air escaping from the sealed unit. Double glazing is made up of 2 pieces of glass with an airtight seal that is filled with air or argon gas. If the seal is damaged then the gas or air can escape. Other causes can be chipped or cracked glass in the unit which can result in condensation building up in the glazing panel. Inefficient and poorly maintained double glazed units can end up with considerable heat loss in the room.

Can a leaded window be changed to clear glass?

Yes, we can convert leaded windows to clear glass sealed units and vice versa.




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