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Why German Windows?

Many customers have asked us why we specialise in German windows and what is so special about them. German windows are subject to an entirely different set of legal manufacturing criteria to windows made elsewhere. German consumer laws require MUCH more stringent quality controls and guaranteed longevity for many products.

And windows are covered by this legal requirement. Many windows currently sold in the UK are made to very low standards. By that, I mean that they use poor quality materials and are often manufactured poorly. Issues like: seals not meeting in the corners of the windows; corners on the windows not aligning; and being able to see daylight between the frame and opener are all too common. When the standard is all the same, and there aren’t many examples of quality manufactured joinery to compare this to. So it’s difficult to know what to look for.

German Building Regulations are also much stricter than here in the UK, so their requirements for energy efficiency and longevity of products is consequently much higher also.

The quality of the German product is, in general, much higher. German manufacturing standards driven by long term legislation is the key.

Timber and Composite Windows

In Wooden and Composite windows, the grade of timber used is often the highest possible quality available with no surface knots on face timber and no finger joints. Within the structure of the frame, these issues are less of a problem. But on the face timber, they are ugly and are one of the first signs of lower quality. Surprisingly, lower grades of timber have a tendency to “move” when they have a few seasons weather under their belt. With movement comes windows that are difficult to open, seals that no longer seal out air and water and failed double glazed units.

Most of our units have a life expectancy of 65-85 years and, in this time, it is very rare to have a problem. Our windows just work long term.

For example, if you look at our composite windows, you will see how each one is made from 6 laminations of timber: 6 individual strips of timber are hot pressed together to make a very stable and strong material from which the window frames are made.

Multiple Seals

Most German Made products have 3 or 4 seals in the frame, and these are continuous even at the corners of the windows. So a non-broken seal is maintained, which in turn is airtight and more energy efficient.Many products currently sold in the UK have only one seal. Often this is cut on the corners so that no continuous seal exists. It won’t, therefore, surprise you that the airtightness of windows without continuous seals is not as good.

Also, look for a final weather seal which is made from butyl rubber. It is probably one of the most durable and flexible materials available and often will last for over 100 years. Seals are also critical in your windows. A fabric covered seal filled with soft foam should ring alarm bells, as the product is life cycle engineered. i.e. designed to fail – requiring replacement after 10-15 years.Our experience of the industry and products in the UK shows that this is pretty common. In Germany, this simply isn’t the case. And products are often still in great condition 50 years down the line. Although, the exception to this rule is PVC which has a shorter life-cycle.For example, looking at our composite windows, again just observe the number of seals.

German window seal

Welded Aluminium Mitres

This is a big issue. We have yet to find another supplier who is offering fully welded aluminium mitres. So we go one step further: by welding, then polishing and only then powder-coating our aluminium external rainscreens.

The commonplace mild acidity in atmospheric moisture attacks bare aluminium and, on most windows, every corner will have a bare aluminium to bare aluminium joint – which is not protected from this environmental corrosion. Over many years, these are the failure points for lower quality aluminium and composite windows and doors.

Glass Quality

We only use German made sealed units that are built to last (again driven by law). Our glass units are carefully built, tested and inspected.

Quality argon gas fills ensure that the unit will perform for many years.

The life expectancy of many of our products is 65-85 years.


On windows and doors which have openers, the quality of the mechanical hardware and locking systems is paramount. We have all been in hotels where the windows don’t seal properly and traffic noise can be clearly heard. This is often due to wear on the hinge mechanisms or locks which no longer pull the window sash hard into the frame, and thus failing to maintain a good seal. For the most part, the root cause of this is often cheap, Chinese-made hardware. For example, metal components aren’t always hardened properly and thus wear prematurely.

This is probably one of the most critical issues. If your hardware isn’t branded, then its VERY likely to be made in the Far East.

In PVC windows, often a high recycled content is used in manufacture. But this is very rare in Germany. PVC windows with recycled content are bad news, as these tend to discolour quickly. It’s a common practice used in the UK and often marketed as a positive when, in fact, it’s a sign that you will be likely replacing your windows in 8-10 years, if they have regular exposure to direct sunlight.

The overall lesson to be drawn is that nobody has ever regretted buying quality.

German windows quality hardware
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Contact us!

For any questions about our products and services, or to get your quote,
please get in touch by phone, email, or using our in-browser contact form!

Midlands : 01608 684 607
Leamington: 01926 935 607
London: 0203 633 0476
E-mail : sales@enlightenedwindows.co.uk
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