How can we choose a good window?

How can we choose a good window? What's the feature of a good window? What should you do when you go to a factory to create a door and window to buy a good quality window?

Doors and windows are an important part of our houses and buildings, affecting buildings in many ways in terms of entering the necessary light into buildings, protecting energy and beauty.
Here we are trying to shed a light on the quality side of the windows how can we recognize the high quality windows and what are the characteristics?
Windows consist of two parts: glass and profile ( frame ) , about the quality of the window profile , we need to know that we can never decide on the outside part of the profile that we see Or bad, but we need to look at the inside of the profile, i.e. take a section from it, look inside the profile, and check the internal contents. When you go to a factory, you want to create a window for your home or building. Give you an example of the profile from which the windows are created and pay close attention to the following points:
The most important part of this profile is Thermal Break, the black plastic section that separates the two parts of aluminum as long as it is wider and has a better size that prevents more heat and cold from passing! If we look at the pictures above, we see that until Thermal Break (the black plastic in the profile) is wider, the U-value of the windows will decrease, meaning there is more defense to the cold and heat. The windows here in Kurdistan are called The normal break sold is about 15mm, and in some places it's 35mm, I think it's no more than here, but in some special types such as the Thermal House Passover, their break is over 50mm!
And it's very important that the space in the window profile be filled with waste, but unfortunately here I haven't seen any factories here that have any gaps in Fill in the profile with a large amount of space, leaving a lot of waste if they can get the windows that are filled in their profiles with the original content will be much better.
We can't talk about all the parts in detail here, but we're trying to talk about the type of glass and their effects so far that double-cup glass is not enough for this weather in Kurdistan, the glass should be 3 cups, and generally the U-value windows for Kurdistan should not exceed 0.90 W/m K.
The glass section will talk about what's coming, in the interest of you dear.
Muslim Mohammad
Passive House Engineer in Iraq