Whilst the sun is great at showing up dirt and smears on windows, it’s best to wait until an overcast day before tackling the job.
It may seem like it makes sense to clean your windows with the warm sun streaming through them, showing up all the dirty patches, but high temperatures and bright sunshine actually create the worst conditions for window cleaning.
During hot and sunny weather, the heat from the sun’s rays causes the cleaning solution to dry on the glass too quickly. This will end up leaving more smudges and smears behind, making it difficult to get a perfect finish. Cool and overcast weather creates the best conditions for achieving a flawless finish when washing windows.
Of course, if it’s the middle of summer, having your windows cleaned on a warm and sunny day may be unavoidable. In this case, it’s best to have the job completed early in the day before the sun gets too high in the sky.