Sliding doors can be finished in almost any colour: aluminium frames are powder coated to a RAL shade, uPVC frames are white or covered in a coloured foil, and timber is stained or painted. The finish you choose affects how the door looks against the brickwork and window frames, how it weathers and, to a modest degree, the price.
This guide covers how each finish works, the RAL colours you will see most often in quotes, textured versus smooth, dual colour, matching existing windows and how finish choices show up in your quote.
How is an aluminium sliding door coloured?
Aluminium frames are powder coated. A dry powder of pigment and resin is sprayed onto the cleaned and pre-treated profile, which is then baked in an oven so the powder melts and cures into a hard, even coat. Good pre-treatment is what makes the finish last, because it helps the coating bond and resists corrosion creeping under it at cut edges and fixings.
The profiles are coated in lengths before the door is assembled, which is why the colour has to be fixed when you order. Some systems offer an anodised-look or metallic powder coat, such as bronze, that gives the appearance of anodised aluminium.
Near the coast, ask whether the system offers a marine-grade pre-treatment, because salt air is harder on any finish.
Which RAL colours are most common for sliding doors?
RAL is a European colour reference system that gives each shade a four-digit number, so a colour can be matched exactly across doors, windows, gutters and other metalwork. These shades come up in most sliding door quotes.
| RAL | Name | Character |
|---|---|---|
| 7016 | Anthracite grey | Dark blue-grey that works with most brick, render and timber cladding |
| 9005 | Jet black | Deep black; crisp against white render and modern extensions |
| 9004 | Signal black, often sand-textured | A slightly softer black, frequently supplied as a fine sand-texture finish (often sold as sandtex black) |
| 9016 | Traffic white | Clean white that sits well beside white uPVC windows |
| 7021 | Black grey | Very dark grey; a softer alternative to full black |
| 7039 | Quartz grey | Warm mid-grey with a hint of brown; suits stone and buff brick |
| Various | Bronze and anodised-look | Metallic warm tones for a more distinctive finish |
Colours look different on a screen, on a small chip and on a full-size frame in daylight, so ask for a physical sample before you decide. We have pages on anthracite grey and black sliding doors if you are choosing between the two.
Should I choose a textured or smooth finish?
Powder coat comes in different gloss levels and textures. A smooth matt or satin finish gives a clean, modern look. A textured finish, often called fine-texture or sand-texture, has a slightly grainy surface that hides fingermarks, light scratches and dust better, and is often used on dark colours such as RAL 9004 and 7016. Gloss is less common on doors because it shows marks.
Texture is part of the colour specification, so RAL 7016 smooth and RAL 7016 textured look noticeably different side by side. Make sure your windows and door are ordered with the same texture and gloss level as well as the same RAL number.
Can the inside be a different colour from the outside?
Yes. Dual colour means the outside of the frame is one colour and the inside another, for example anthracite grey outside to match the windows, and white or a lighter grey inside to suit the room. Thermally broken aluminium frames have separate inner and outer sections joined by an insulating bar, so each side can be coated separately before assembly.
Dual colour typically adds about 7% to the guide price, because each profile is coated twice and handled separately through production.
What colours are available on uPVC and timber sliding doors?
uPVC frames are usually white through the material. Other colours are applied as a foil, a thin laminated film bonded to the profile, available in plain colours such as anthracite grey and black and in woodgrain effects with a light embossed texture. Foils can be specified on the outside only, with white inside, or on both faces.
Timber sliding doors are finished with stains or opaque paint systems, usually factory-applied in several coats. Stains let the grain show through; opaque paints give a solid colour. Timber finishes need recoating over time, and how often depends on how exposed the elevation is. Alu-clad doors have a powder-coated aluminium skin outside and timber inside, giving a low-maintenance exterior with a natural interior. See our timber sliding doors page for the options.
How do I match a new sliding door to my windows?
If your windows are already coloured, find out the RAL number or foil name before you choose. It is often on the paperwork from when they were fitted, or the surveyor can compare a sample against the frames on the day. Existing frames may have faded slightly over the years, so a new door in exactly the same RAL can look a shade fresher at first.
Matching is not only about colour. Gloss level, texture, handle finish and the visible width of the frame all affect whether the door looks like part of the same set.
Replacing doors on a house is usually permitted development if the new doors are similar in appearance. If you live in a flat, a listed building or a home covered by an Article 4 direction, a change of colour or material may need consent, so check with your local planning authority first.
How do colour and finish affect the price?
- A set range of standard colours is included in the guide price for aluminium doors.
- A special RAL colour outside that range adds a fixed extra, shown as a line in your quote.
- Dual colour adds about 7% to the guide price.
- Foiled colours on uPVC typically add around 12% to the guide price.
- Timber stain and paint choices are priced with the door and confirmed in your quote.
Whatever you choose, the colour, texture and finish for both faces are written into your quote, and nothing is ordered until you confirm the surveyed specification in writing. You can start a quote online and add your colour choices as you go.
Powder coat needs little more than washing with warm water and a mild detergent a few times a year, more often near the coast. Avoid solvents and abrasive pads, which can dull any finish.
Common questions
What is the difference between RAL 7016 and RAL 7021?
Both are dark greys. RAL 7016 anthracite grey has a slight blue undertone and reads as a strong dark grey, while RAL 7021 black grey is darker and closer to black, with a softer look than full black. The difference is clearer on a full-size frame in daylight than on a screen, so ask to see samples of both.
Does a black sliding door get hot in the sun?
Dark frames absorb more heat than light ones, so a black or dark grey frame on a sunny south or west elevation gets warmer to the touch. Powder-coated aluminium copes well with this. Dark foils on uPVC are more sensitive to heat, so some systems only allow them on certain profiles or sizes, which we check when we specify the door.
Can I change the colour of my sliding door later?
Aluminium frames can be re-coated on site with specialist spray systems, but the result is not the same as factory powder coating and may not last as well. Foiled uPVC can also be re-sprayed by specialists. It is far better to settle the colour before you order, because the profiles are coated before the door is made.
Is a textured finish harder to clean?
Not really. A fine-texture powder coat can hold a little more dirt in its surface, but it hides fingermarks and light scuffs better than a smooth finish. Wash it with warm water, a mild detergent and a soft brush or cloth, then rinse and dry. Avoid abrasive pads and solvent cleaners, which can dull any powder coat.