Adapting wooden window frames to take a double glazed unit (DGU)

[anishtom]

Hi,
My house got a extention made with timber and has got a 2 single glazed glass window (fixed one) due to this in winter the room is too cold. As it made with timber i can`t install upvc double glazed window. But I am thinking insted of single glazed unit can i able to fix a double glazed unit with out upvc. where can i able to buy double glazed sealed unit?
thanks

[stevenc1603]

Firstly there should be no reason why you cant remove the wooden window and have a UPVC one inserted in its place, unless there are planning restrictions stopping you of course.

You can get wooden framed double glazed units made to fit the size you need.

You can adapt most wooden window frames to take a double glazed unit (DGU) by routing out the glass rebate to take the thicker DGU.

How about fitting much cheaper secondary glazing to the windows?

[anishtom]

Could you tell me what is secondary double glazing please and how can i do that
Thanks