Why some buildings always look dirty – and what facade design has to do with it
Some buildings age gracefully; others age disgracefully. We’ve all seen buildings that start looking tired, dirty, or water-stained far sooner than they should. It’s frustrating, because our whole intent as an industry should be to create buildings that look good not just when the scaffolding comes down, but for years afterwards.
And it almost always comes down to poorly considered detailing and a lack of specialist involvement. Water is incredibly revealing. So if it isn’t managed properly, it tracks down surfaces, picks up dirt, and carries it across the building. You start to see staining below copings, around windows, beneath balconies, and anywhere across the facade where a funnel of water has been allowed to find its own path.
There can be other factors at play; for instance, construction dirt can find its way onto the facade, while salts from masonry and mortar can be carried by rainwater runoff and affect adjacent finishes.
Individually, these things might seem relatively minor, but once water starts carrying them across a building, they can become very visible. At LockMetal, we recognise a lot of thought goes into how a building should look when it’s new. But we spend just as much time thinking about how it will look five, 10, and even 20 years later.
That long-term thinking is central to how we approach facade design and delivery. You can find out more about our approach here.
You have to design where the water goes
To start, designing for the UK is particularly important. We have rapid weather cycles, long periods of damp and low sun, driving rain and, occasionally, lots of sunshine. On an exposed elevation, rain doesn’t simply fall vertically: wind can drive it sideways, upwards, into joints, and across soffits.
Orientation matters, too, with factors such as shade and low sun contributing to moisture retention and algae growth on some elevations.
Eventually, though, gravity has to bring that water down somewhere. That’s why apparently small details such as drips have a key job; they break the surface tension of water and move it away from delicate parts of the building.
If a drip is missing, too shallow, too close to the face, or affected by installation tolerances, the consequences can become very visible. Therefore, the facade has to be designed with how water actually behaves in mind, not how we wish it behaved on a clean drawing.
The beauty is in the detail
The details that affect how a building ages are often the ones that look relatively minor on a drawing.
How do the joints work? Where is the water going from and to? How do the sills and their corners work? Is the overhang sufficient? Have tolerances affected it? How does the detail interact with windows, masonry, or balustrades? Has silicone been positioned in a way that could create a dirt trap?
Material and finish selection also matter: different finishes hold and reveal dirt differently. Smooth finishes may show streaking where water becomes concentrated; textured ones may disguise some marks but retain more dirt; and light colours can expose runoff paths very quickly. That's why we see finish selection as a maintenance and lifecycle decision, as well as an aesthetic one.
The quality of that finish is equally important
We’ve all seen buildings where powder coating has faded or become chalky or inconsistent over time. At LockMetal, we use QUALICOAT-approved finishes and pay close attention to the powder coaters, anodisers, and manufacturers we work with.
This is because the quality controls behind the finish have a direct bearing on how it will perform and look in the years ahead. Material choice also creates opportunities to achieve the architectural intent in a more maintainable way.
For example, we’ve used polyester powder-coated stone-effect aluminium as an alternative to GRC or natural stone. It can achieve the desired visual look and provide a surface that is cleanable, maintainable, and less susceptible to staining and damage over time.
Thinking beyond the day of handover
Designing with maintenance in mind is something we care passionately about at LockMetal; our designers always consider how a building is actually going to be looked after.
How will it be cleaned? Can we design it so it doesn’t need cleaning as often? If a panel needs replacing, can it be removed and reinstated without forever sticking out like a sore thumb?
It’s all about thinking beyond the day of handover. Our Heathside & Lethbridge project is a good example of this, involving over 80 different sill and panel types across curved facades, projecting and inboard balconies, large soffit areas, and rainwater goods.
Our team had to consider how the copings would shed water away from the masonry, how intricate curved sill details would perform, which coatings were appropriate for the different areas, and how soffits could be demounted when access to services was required.
Buildings can age and still look good
None of those decisions were simply about making the building look good on day one. They were about helping it stay that way.
The lesson is simple. Get it right the first time, and you avoid the build-up of cleaning costs, remedial work, and problems that come from poor detailing or compromising the quality of the design.
Because buildings don’t need to look tired and old. They can age and still look good. That’s what beautiful means to us at LockMetal: creating buildings that remain beautiful for the duration of their designed life.
Not sure how material choice, detailing, and maintenance will affect the long-term appearance of your facade? Click to learn more about our approach to specialist facade design.
