3D Full Cover Foiling on PVC Windows: What It Is and Why Choose It

What is 3D foiling or Full Cover on PVC windows?

3D foiling, also known as Full Cover, is an advanced coating technique where a coloured film is applied to all three visible sides of the PVC profile: the exterior face, the interior face and the rebate — the inner edge of the frame and sash that becomes visible when the window is opened.

On a window with conventional foiling (1 or 2 sides), opening the sash reveals a strip of white PVC on the rebate, breaking the aesthetics of the finish. With 3-sided foiling, that strip disappears completely: colour and texture wrap around the entire profile, achieving a uniform, high-end finish regardless of whether the window is open or closed.

To understand why this matters, it helps to know the difference between profile manufacturer, fabricator and installer. This technology is especially relevant for wood-effect finishes, where visual consistency is essential for a realistic result.

Types of foiling on PVC windows: 1, 2 and 3 sides

To understand the importance of 3D foiling, you need to know the three foiling options available on the market:

1-sided foiling

The foil is applied only to the exterior face of the profile. The interior remains white. This is the most common option when building regulations or the architectural project require a specific colour on the facade, but the owner prefers to keep the interior white.

• Advantage: More affordable price.
• Disadvantage: From the inside, the window appears white, with no customisation.

2-sided foiling

Foil is applied to the exterior and interior faces of the profile. They can be the same colour or different colours (e.g. dark wood on the outside and light wood on the inside). This is the most popular option for residential renovations seeking full customisation.

• Advantage: Colour on both sides, ability to combine finishes.
• Disadvantage: When the window is opened, the rebate remains white, breaking the uniformity of the finish.

3-sided foiling (Full Cover)

Foil is applied to the exterior, interior and also to the rebate of the frame and sash. This is the most complete and premium finish on the market. When you open the window, the entire visible profile maintains the same colour and texture.

• Advantage: Complete finish with no visible white PVC. Perfect visual result.
• Disadvantage: Higher cost than 1 or 2-sided foiling.

KÖMMERLING 76 with NaturKolor76 and Full Cover technology

KÖMMERLING is one of the leading PVC profile brands that has innovated the most in foiling, and its KÖMMERLING 76 system (also known as KÖMMERLING Xtrem 76MD) is compatible with its NaturKolor76 finish range, which includes Full Cover technology.

NaturKolor76 offers a total of 76 foiled colours distributed across 5 ranges:

• Wood: Oak, walnut and chestnut with natural textures and realistic grain.
• Premium Wood: High-end wood finishes with deep textures and a real feel.
• Metal: Metallic finishes that replicate anodised aluminium, corten steel and other metals.
• Solid: Uniform colours without texture, from whites to anthracites and blacks.
• Textured Solid: Uniform colours with a surface texture that provides a pleasant feel and reduces fingerprint visibility.

All these finishes are available with the Full Cover (3-sided) foiling option, allowing the rebate of both frame and sash to be coated with the same finish as the rest of the profile.

PX Technology: solar protection and extended guarantee

One of the most important aspects when choosing a foiled window is the durability of the finish against sunlight. UV rays are the main enemy of coloured foils, potentially causing discolouration and degradation over the years.

KÖMMERLING has developed PX technology, a special solar protection treatment applied to its foils that offers:

• Plasticiser-free: Greater chemical stability and less long-term degradation.
• Solar shield effect: Reduces the temperature absorbed by the profile, protecting the colour.
• 22,000 hours of solar exposure testing: No signs of physical failure after this extreme test.
• 15-year colour stability guarantee: KÖMMERLING was the first company in the sector to offer this extended guarantee on all foiled colours with PX technology.

This 15-year guarantee is especially relevant if you live in an area with high solar exposure such as the Costa Brava, Girona or Barcelona, where south or west-facing windows receive intense radiation throughout the year.

mattex and woodec: KÖMMERLING's ultra-matt finish

In addition to traditional foils, KÖMMERLING offers in its European catalogue (also available through fabricators in Spain) the mattex and woodec lines:

• mattex: Foils with an ultra-matt surface that replicate the look of powder-coated aluminium. Available in colours such as deep black, anthracite grey and white. The feel is velvety and very pleasant.
• woodec: Ultra-matt foils with deep-textured wood imitation. The visual result is virtually indistinguishable from real wood, even up close.

These finishes represent the latest trend in window design in Europe, where the matt, minimalist look is gaining ground over traditional glossy finishes.

When should you choose 3-sided foiling for your windows?

Full Cover 3-sided foiling is the best option in these situations:

• Wood-effect finishes: If you want your windows to look like real wood, the white rebate completely breaks the illusion. 3-sided foiling is essential.
• Frequently opened windows: In rooms where windows are opened daily (kitchen, living room, bedrooms), the rebate is constantly visible.
• High-end interior design projects: If you are investing in a carefully designed interior, the windows must match in every detail.
• Tilt-and-turn windows: In the tilt position (ventilation), the upper rebate is partially visible from inside.
• Dark colours: The contrast between an anthracite or black exterior and the white rebate is very noticeable. With 3D foiling it disappears.

Technical specifications of the KÖMMERLING Xtrem 76MD system

The profile that supports the entire NaturKolor76 and Full Cover range is the KÖMMERLING Xtrem 76MD, a state-of-the-art system:

Feature	Value
Profile depth	76 mm
Air chambers	6 chambers
Profile transmittance (Uf)	1.0 W/m²K
Window transmittance (Uw)	From 0.80 W/m²K
Seals	Triple centre seal + 4th seal on sash
Glazing maximum	Up to 48 mm (triple glazing)
Passivhaus certification	Yes (warm-temperate climate) — see what Passivhaus is
Air permeability	Class 4 (maximum)
greenline® profile	100% recyclable, lead-free

These specifications make the KÖMMERLING 76 one of the best options on the market for projects seeking maximum energy efficiency combined with customised aesthetics thanks to the NaturKolor76 range.

Frequently asked questions about 3D foiling on PVC windows

Is 3-sided foiling more expensive than 2-sided?

Yes, Full Cover foiling has an additional cost over standard 2-sided foiling, but the difference is not as large as you might think. It generally represents an increase of between 10% and 20% over the price of 2-sided foiling. Considering that windows are a 30-40 year investment, the additional cost is minimal compared to the aesthetic result achieved.

Does 3-sided foiling affect the window's performance?

No. Foiling is a surface layer that does not alter the thermal, acoustic or weathertight properties of the profile. The technical performance of the KÖMMERLING 76 remains identical with any type of foiling.

Can I choose a different colour on the rebate from the exterior and interior?

Typically, 3-sided foiling applies the same interior colour to the rebate. That is, if your window has dark wood on the outside and light wood on the inside, the rebate will be in light wood (the interior colour). However, it is worth checking availability with your fabricator, as options may vary.

Is Full Cover foiling available in all NaturKolor76 colours?

Most of the 76 colours in the NaturKolor76 range are available with the Full Cover option, but there are some exceptions for special or low-demand colours. Your installer can check exact availability with KÖMMERLING.

What guarantee does KÖMMERLING foiling have?

KÖMMERLING offers a 15-year guarantee on colour stability for all foils with PX technology, which covers virtually their entire current catalogue. It is the most comprehensive guarantee in the sector in Spain.

What is the difference between KÖMMERLING and Ecoven Plus regarding foiling?

Both brands offer high-quality foiling. KÖMMERLING stands out for its range of 76 colours (NaturKolor76) with Full Cover and PX technology, while Ecoven Plus offers a wide range with exclusive finishes such as Spectral (ultra-matt) and the option of different foiling on interior and exterior. See our full manufacturer comparison.

Conclusion: 3D foiling makes the difference

If you are looking for PVC windows with a premium finish, 3-sided (Full Cover) foiling is a detail that makes a significant difference to the end result. That white edge that appears when you open the window may seem like a minor detail, but when you compare it with a uniform Full Cover finish, the difference is clear.

At Instal Tancaments we are specialist KÖMMERLING installers in Girona and the Costa Brava. We regularly work with the NaturKolor76 range and can advise you on which finish best suits your project.

If you would like to see real samples of foiled finishes or need a quote for your windows, contact us with no obligation. We will personally advise you on the best options for your home.