I purchased my flat 3 years ago and the draught from my upvc windows is quite bad, so I contacted several draught proofers in the hope of remedying the problem. Nobody seems to want to take on the work because apparently draught proofing upvc windows is next door to impossible :( is this true? Are there any alternative methods I haven't considered?
upvc windows normally have drought proofing strips on the frame for the window to close against. My own experience is that the sliding bar system which is effectively the hinge becomes dirty and stiff over time and prevents the window closing tightly at the opposite end to the lock. If you open the window and clean these parts then spray them with WD40 they will close more smoothly and not leave a gap.Hope this helps it is a very cheap solution.
P.S. don't forget the same mechanism is at the top as well as the bottom.
The first thing to check is the condition of the existing seals. If these are damaged I think new ones can be purchased.
If the seals are OK, the window isn't being pulled tightly against them and it may be possible to adjust the keeps. (That's the part the window catch engages with on the frame).
As the previous poster suggests, ensure the hinges are clean and lubricated and there is no debris around the frame obstructing correct closure.
If you find that replacing the correct seals is too expensive, you can purchase rolls of sticky backed Foam Rubber Strip at the likes of B&Q
If the seals are OK, the window isn't being pulled tightly against them and it may be possible to adjust the keeps.
A word of warning. When you adjust the pressure on the keeps, you also increase the pressure on the opening system. I found out the hard way when two of the handles sheared at the spindle entry.
Be careful of using WD40 as this can become sticky after a while. I use 3in1 silicone spray instead and find it much better