Flagship guide · 9 min read
The Ultimate Guide to Aluminium Windows
Everything worth knowing before specifying aluminium windows, from frame construction and thermal performance to colour, glass and realistic pricing.
Dual-Colour Aluminium Windows Explained
A dual-colour aluminium window gives you a different powder-coated finish inside and out from the same frame, letting an exterior make a statement while the interior stays calm.
3 min read
Written by Windows in the Lakes · A trading name of Home Glazing Ltd
Dual-colour aluminium windows are powder coated in two separate finishes — one applied to the outer face, a different one to the inner face — during manufacture, allowing a bold or dark exterior colour that suits the building's setting to be paired with a lighter, warmer or more neutral internal colour that suits the room. It is a standard option on most premium aluminium systems, typically at a modest premium over a single colour throughout.
This guide explains how the process works, why homeowners choose dual colour, common colour pairings, and what to check before specifying it.
How dual-colour powder coating actually works
Rather than painting a finished frame two colours, which would not achieve the same durable, factory-baked finish, dual-colour aluminium windows are typically fabricated from sections powder coated separately before final assembly, or coated with the two colours masked in sequence, so both faces achieve the same hard-wearing, UV-stable finish as a single-colour frame. The process adds some manufacturing time and cost but does not compromise durability.
Why homeowners choose dual colour
- A dark or bold exterior, such as anthracite or black, suits a contemporary elevation or matches other cladding and roofing materials
- A lighter internal colour, such as white or a soft grey, keeps rooms feeling bright and makes it easier to coordinate with interior decor
- Conservation or planning requirements sometimes favour a particular external colour that would feel heavy used throughout a room
- Resale flexibility — a neutral interior ages better against changing interior trends than a bold colour used both sides
Common colour pairings
| External | Internal | Typical effect |
|---|---|---|
| Anthracite grey (RAL 7016) | White or off-white | Sharp contemporary exterior, bright interior |
| Jet black (RAL 9005) | Light grey | Strong contrast exterior, calm neutral interior |
| Heritage green | Off-white or cream | Traditional exterior with a softer interior tone |
| Matching darker tone | Slightly lighter shade of the same colour | Subtle rather than contrasting effect |
Practical considerations before specifying
Dual colour is available on most premium aluminium systems, but availability and any cost premium should be confirmed for the specific system quoted rather than assumed, since not every colour combination or every system offers it as standard. It is also worth viewing a physical sample of both colours together, since colours can interact differently in combination than either does viewed alone.
Decision criteria
- Bold contemporary exterior, bright interior wanted
- Dark external, light internal dual colour
- Conservation area with an approved external colour
- Confirm dual colour is acceptable, or match single colour
- Consistent look preferred throughout
- Single colour may be simpler and slightly cheaper
- Time-sensitive project
- Confirm dual-colour lead time against the programme
Common mistakes
- Choosing a colour pairing from a brochure without viewing physical samples together
- Assuming dual colour is available on every system without checking
- Overlooking the slightly longer manufacturing lead time for dual-colour frames
- Selecting a bold internal colour that clashes with planned interior decor decided later
Next step
Considering aluminium windows for your own project?
We design, specify and install across Cumbria, the Lake District and the wider North. Send drawings, photographs or simply a description of the building and we will tell you what is possible and what it should cost.
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Relevant colours
Colours StudioAnthracite Grey · RAL 7016Jet Black · RAL 9005Pure White · RAL 9010
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