The short answer
Usually, yes. Window cleaners work in the rain because a pure-water clean isn’t spoiled by rain: the glass and frames have already been scrubbed and rinsed with purified water, so there’s no dirt or detergent left for the rain to smear. What stops a clean is weather that makes the work unsafe: thunder and lightning, high winds or freezing conditions. Then the visit should be rearranged.
It’s one of the questions facilities managers ask us most, usually after spotting a window cleaner at work in a drizzle and wondering whether it’s money well spent. The answer comes down to how the windows are cleaned, and what really makes glass look dirty after a shower.
Why window cleaners work in the rain
Most commercial windows are now cleaned with water-fed poles. Purified water is pumped up the pole to a soft brush, and the cleaner scrubs the glass, frames and sills, then rinses everything down. Purified water has had the minerals taken out, so it dries without leaving spots, and nothing needs to be wiped or polished.
That’s why light rain doesn’t undo the work. By the time the rain lands, the dirt has already been scrubbed off and rinsed away. Rainwater itself is relatively clean compared with tap water, so on freshly cleaned glass and frames there’s very little for it to leave behind.
It’s also why your windows are wet when we leave. Pure water is left to dry on the glass, and wiping it would only spoil the finish. How we clean.
Why windows look dirty after rain
If rain were the problem, windows would look worse after every shower. The marks people blame on rain usually come from what the rain washes down:
- Dirty frames and sills. Dirt left on the frames runs onto the glass in the next shower and dries as streaks. That’s why we clean the glass, frames and sills on every visit.
- Dust and traffic film. Buildings near main roads, car parks and building sites collect a film that rain turns into spots and runs.
- Glass that hasn’t been cleaned for a while. Rain on dirty glass mixes with the dirt already there, and it shows when it dries.
- Tap water. Glass cleaned with ordinary tap water can be left with mineral spots, which are easy to mistake for rain marks.
So the best protection against rain marks isn’t avoiding wet days. It’s a regular clean that includes the frames. How often should commercial windows be cleaned?
When the weather does stop a clean
We can keep working in fairly heavy rain. These are the conditions that stop us:
- High winds. A long pole is hard to control in strong gusts, and every cherry picker has a maximum wind speed set by its manufacturer. We never work in high winds.
- Thunder and lightning. Water-fed poles are long and often made of carbon fibre, which conducts electricity, so we never work when there’s thunder or lightning about.
- Freezing conditions. We’re cautious when it’s icy. Hoses and pumps can freeze, so the water can’t flow and the job can’t be done. And water running off the glass can freeze on paths and entrances, leaving a slip hazard for your staff and visitors.
- Anything that makes the ground unsafe for a ladder or a cherry picker, where one is needed.
If the weather stops a clean, we’ll get in touch and send you a new date by email. You can confirm it with one click, or leave us a message if another day suits you better. Every clean is scheduled in advance and confirmed with you, so you always know when to expect us.
Shop fronts and internal glass
Not every window is cleaned with a pole. We clean shop fronts and internal glass by hand where that gives the best finish. Heavy rain makes traditional hand cleaning on outside glass harder, because the squeegee can’t leave the glass dry. Internal glass, partitions and screens aren’t affected by the weather at all, so they can be cleaned whatever it’s doing outside.
Window cleaning in winter
Wet, dark months are when clean windows matter more, not less. Low winter sun shows up every smear, lit windows are on show for longer on dark afternoons, and road grime builds up faster in wet weather. Stopping cleaning over winter usually means glass that takes longer to put right in spring. What happened when Morrisons cut its window cleaning.
If you manage a building
- Don’t cancel a clean because of light rain. A pure-water clean still does the job.
- Tell your window cleaner about entrances and paths that ice over, so run-off can be planned around them.
- Ask your window cleaner how rained-off or frozen-off visits are rearranged, and how you’ll be told.
- If windows look streaky after rain, check whether the frames and sills are being cleaned too.
Choosing a contractor? How to choose a commercial window cleaner.
Questions
Can windows be cleaned in the rain?
Usually, yes. Light rain doesn’t normally spoil a pure-water clean, because the glass has already been scrubbed and rinsed with purified water. If it isn’t safe to work, such as in thunder and lightning, high winds or freezing conditions, we’ll rearrange your visit.
Does rain clean windows?
Not really. Rain can rinse off loose dust, but it won’t shift traffic film or dirt on the frames, and it often carries dirt down onto the glass. A proper clean includes the frames and sills.
Why are my windows wet after a clean?
Because pure water is left to dry on the glass. It has nothing in it to leave a mark, so the windows dry clear without streaks, and wiping them would only spoil the finish.
Do you work in heavy rain?
Often, yes. We can keep working in fairly heavy rain, but never when there’s thunder or lightning, or in high winds.
What happens if the weather stops my clean?
We’ll get in touch and email you a new date. You can confirm it with one click, or leave us a message to arrange a different day.
Photo: Artem Zhukov on Pexels.
