When should you clean your building facade? 6 signs it's time
When should you clean your building facade? The signs it's time: dark streaks under windows, limescale on glass, blackened stone and pigeon droppings, and how to clean without disruption.
There is no single cleaning frequency that suits every facade. Two buildings on the same street can get dirty at completely different rates, depending on the cladding, the direction they face and their immediate surroundings. So rather than following a fixed schedule, it's worth knowing what makes a building dirty and recognising the signs that it's time.
What decides how quickly a facade gets dirty
- Proximity to the sea – salt and humidity cling to glass and metal and leave a cloudy film.
- A main road or industrial area – soot and fine dust build up mainly on the lower floors and on sills.
- Nearby building sites – construction dust settles on every horizontal surface and on the glass.
- Cladding type – glass shows every mark, stone and exposed concrete absorb dirt, and aluminium shows water streaks.
- Facade orientation – a facade exposed to sun and rain gets dirty differently from a shaded one.
- Pigeons and birds – droppings on sills and ledges build up quickly and damage materials.
6 signs it's time to clean
1. Dark dirt streaks below the windows
Rainwater washes dirt off the sills and leaves vertical streaks down the facade. This is usually the first sign you notice from the street.
2. Water spots and limescale on the glass
White or cloudy marks that don't wash off in the next rain point to a build-up of minerals and dirt on the glass.
3. Blackened or stained stone or render
Stone and render darken gradually, and it can be hard to notice until you compare them with a sheltered area or an old photo of the building.
4. Pigeon droppings on sills and ledges
Beyond how it looks, built-up droppings can damage facade materials over time, so it's best not to wait.
5. A layer of dust after nearby construction work
After a nearby building or renovation project, the facade and windows are usually covered in a layer of dust that is especially noticeable on glass.
6. Before an event, sale or letting of the property
A clean facade shapes the first impression residents, customers and buyers get, so it's a good time to clean even without obvious signs.
How to clean without disruption
The drone washes the facade from the ground, with no scaffolding and no workers at height, and work can also be done after hours and at night. At the end of the job you get a summary report with photos.
For the full guide, see drone building facade cleaning. Send us a video of your facade and get a quote.