What should you look out for? How do they work in practice?
The more you move toward frameless, the more technically complex they become, and no one is doing it to play the price down (except maybe up).
In today's triple-glazed patio doors, it's not the frames that are heavy, but the weight that needs to be held steadily in place. The hardware technology is also high-tech: thin frames (and even more so frameless – though: somehow several individual panes have to be connected together, so something has to go around the edge).
And in the event of damage, you can't just call in a random glazier to repair it. How long can a supply company last, how compatible are competitors' systems?
These are questions that a five-star hotel doesn't ask itself, but a designer home builder probably does-and either way, they're not aiming for market share among regular citizens.
We installed 2 folding systems (originally planned on 4, but it turned out to be too expensive for us).
But we haven't moved in yet, there is still work going on inside.
The Highline model, each 3600 wide and 2120 high, has 4 sashes, each of which tilts outward, so there are no exterior shutters. Triple glazing, as is the exterior wall.
What is the best way to darken windows at night?
We built (detached house with a gable roof, first and second floors, clinker exterior walls). We have roller shutters on the first floor.
Now we are looking for a way to darken the windows on the top floor as much as possible so that the light from outside (streetlights, etc.) hardly penetrates. Foil is out of the question as it would darken the entire room. Unfortunately, we have noticed that many of the blinds that are upgraded always have certain "slits" around the edges that let in a lot of light. It's also difficult that the window is built into a sloping roof.
Can you recommend certain products that, in your experience, almost completely shield the room from light at night?
There are guide roller shutters for the window (Velux) in the slanted roof. They are really tight if you choose the right fabric.
You can probably find something similar for regular windows.
The most common roller blind that runs in front of the wall also works well. Heavy curtains will also work, but are likely to be unfashionable.
Get very simple roller shutters. They are also available for skylights. And do an excellent job.
For a regular window in one room, we have gray blinds from Ikea. Nothing goes through it.