Although uPVC is still a very popular option it is very worthwhile to consider using a lightweight metal such as aluminium in the frames.
Older designs had real problems with internal condensation on the frames but nowadays modern design & manufacturing techniques have eliminated all the “bugs” and what you get for your money is an excellent product.
The installation can be fitted direct to the opening or you can opt for a wood sub-frame (normally hardwood), on real terms the difference is only visual and can come down to the individual preference of the clients. They do have, however, some particular advantages over uPVC Windows when it comes to design & appearance.
Basically, you should opt for the best rated windows that you can buy for your money, broadly speaking that means opting for a window design that reduces the flow of heat or cold from one side to the other and is generally mentioned as the “U-value”.
As you can see from the pictures the internal design of the frames has a big impact, the second has more chambers, more insulation, warm edge spacers & triple glazing, but as you would expect, higher performance usually comes with a higher buying price.
UK Window & Door Ratings are awarded by the British Fenestration Rating Council – A really high performance window can almost reproduce the same thermal qualities as a cavity wall.
CE Marking Requirements for Windows and Doors
Legislation was passed in 2013 that covers glazing products that get sold in the EU and covers both safety & energy efficiency. Any installation that you buy should have the CE mark somewhere on it and this demonstrates that the product has been tested and passed the minimum criteria (Initial Type Testing).
You can find out more about windows & doors on our main site here