Schuco AWS Aluminium Windows Explained (Without the Marketing Fluff)
Schuco's window catalogue is genuinely enormous. If you've been quoted "Schuco AWS windows" and you have no idea whether you're getting the entry-level version or the top-of-the-line thermal super-window, this article is here to clear it up.
What "AWS" Actually Means
AWS stands for Aluminium Window System. Not romantic, but at least descriptive. The number after AWS (70, 75, 90) refers to the frame depth in millimetres. Deeper frame = more thermal break = better U-values, but also chunkier sightlines.
The main platforms you'll see in 2026:
- AWS 70 — entry to the modern range. Good for standard replacement work.
- AWS 75 — the "sweet spot" for most Potters Bar and Barnet new-build extensions.
- AWS 90 SI+ — highly insulated for Passivhaus-adjacent work.
- AWS 120 CC.SI — specialist high-performance, rare in domestic work.
Sightlines and how they read on a house
The visible frame width on AWS 75 is around 108 mm at a standard casement mullion. That's slim by aluminium standards but bulky next to a Crittall-style steel window. If you're chasing minimal sightlines on a heritage-look project, look at our Jansen steel windows article for the alternative approach.
U-Values: What the Numbers Actually Mean
U-value is watts per square metre per degree Kelvin. Lower is better. A single-glazed Victorian sash sits around U 5.0. A modern double-glazed casement is 1.4–1.6. Anything under 1.0 is "high performance".
Rough Uw figures for AWS with 4/16/4 double-glazed argon-filled units:
| System | Typical Uw | Notes |
|---|---|---|
| AWS 70 | 1.4–1.6 | Fine for like-for-like replacement. |
| AWS 75 | 1.2–1.4 | Sensible for extensions targeting current Part L. |
| AWS 90 SI+ | 0.9–1.1 (triple) | Overkill for most, essential for Passivhaus. |
Where AWS Fits in Real Local Projects
On rear extensions and side returns in Cuffley and Brookmans Park where we've seen recent work, AWS 75 is the go-to. It matches sliding doors from the ASE line beautifully (same colour palette, same visual language) and hits current thermal targets without going into triple-glazed territory.
For a full replacement project on a 1930s house in Potters Bar, we'd generally lean AWS 70 or AWS 75, unless the client wanted the slimmest possible frames, in which case a heritage-look system is a better route.
Colour, Finish and Long-Term Look
Powder-coated aluminium windows should last 25+ years without visible degradation if the finish is done to spec. Popular colours locally:
- RAL 7016 (anthracite grey) — the default for modern extensions.
- RAL 9005 (black) — more heritage/Crittall-style look.
- Bespoke or dual-colour — grey outside, white inside, for example. Costs more but looks great.
Where to Buy Locally
Schuco AWS windows are supplied via authorised fabricators and installers. If you want to compare finishes in person, 5EC's aluminium window pages cover the AWS range along with a couple of alternatives — useful for cross-shopping if you're weighing up Schuco against, say, Cortizo or a timber-alu system.
The Short Answer
AWS is a mature, well-supported system. AWS 75 is the right pick for most Home Counties projects. Only spec AWS 90 SI+ if your architect has explicitly asked for it — you're paying for headroom you might not use. And always ask for the Uw figure for the actual window you're buying, not the brochure best case.