We had two new Velux UPVC windows fitted in November 2022 and went with the 62 glazing as top of the range. Codes: GGU PK10 0062 with BDX PK10 2000   When -1C/-2C outside we've had condensation on parts of the frame, and I thought they had slight air leaks at the top. So I got the installer back who said "nothing to do with me" and raised with Velux Technical support.   Velux technical support have said that  "Condensation is an environmental issue, there is too much moisture