Condensation can also form on the window’s exterior. This is completely normal and indicates that the window is thermally efficient. On the other hand, if condensation is able to be seen on the interior of the window, it signifies that there is an issue with the glass seal. Defective seals can lead to cloudy or blown-out double glazing, no matter what the cause. Garden Rd, Brighouse HD6 2AX 07595510190 https://doubleglazingrepairbrighouse.co.uk/ read full review »