Trefz window prices and experiences?

Hello everyone,

what do you think about the following window from the company Trefz, does anyone know it? What should we pay attention to when choosing windows? It is intended for a new building, exterior walls made of Poroton T10 brick.

Kunststofffenster S8000 mit Anschlagdichtung (Außenansicht)
Thanks to the classic 74 mm window construction
with 4- or 5-chamber plastic profile technology,
the S8000 with sealing lip is recommended for the installation of double or triple insulating glass (Ug value 0.6 W/m²K) and soundproof as well as burglar-resistant glazing. A continuous frame and sash seal each ensure optimal tightness.
A special feature is the outer weather-resistant, matt ground acrylic layer, which provides the noble color finish of the S8000.

Regards

That reads like sales talk and product promotion. If the price and technical specifications matched each other, that would probably be better than this novel.

Yes, that is also the product promotion from the manufacturer.
Therefore, also the question of what technical data are important for windows, what should be paid attention to?

You might be particularly interested in the insulation effect.

So Ug (glass), Uf (frame), and then of course the overall window (Uw). The smaller the window, the greater the weighting of the frame part.

So it would probably be advisable to place special emphasis on Uw.

And then you should look at which resistance class the windows have. However: Whoever wants to get in, will get in. So RC 1 or 2. Anything above that gets very expensive and the conditions also have to be right. What good is RC4 if you then simply take the window including the frame apart.

And depending on the location, sound insulation is probably also interesting. But even there there are limits. The room is only as quiet as the weakest component, whether wall, window, or possibly ventilation.

We focused on burglary protection before choosing the windows.

After that, about 3/4 of the manufacturers were already eliminated because they could not deliver/build what we wanted.

In addition, as I have learned, different window sizes and the difference between casement and fixed glazing also have different twilight effects.

So the overall calculation must add up.

If everything fits, you can then consider design, price, and recommendations.

Just browsing the internet is usually not enough.

What does your planner say?

And then you should look at the resistance class of the windows. However: whoever wants to get in, will get in. So RC 1 or 2. Everything above that gets very expensive and the boundary conditions also have to be right. What good is RC4 if they just take the window along with the frame apart right away.

Here’s something else.

We have RC3. Everywhere. So 11mm laminated safety glass, plus a bunch of mushroom head locks (a patio door then has, I believe, 16 or 17 bolts). Lockable handles. But they are already quite secure even when unlocked, because they latch when closed.

The glass is a bit darker through the laminated safety glass than with normal glazing. And you can see that even without a direct comparison. You just have to live with that.

The windows are all screwed into the masonry on the sides with a distance of about 20 - 25 cm and have brackets at the top and bottom. So the window cannot be pried out of the masonry during a break-in attempt.

Cheap is a different story. But at least you don’t want to make it too easy for anyone.

Secure the doors accordingly.