How 'slim' are slimline windows?

[Pete574]

I am in the middle of ordering new slimline windows and I find it difficult to get answers from suppliers on how exactly thick the window frame will be.

Is there a specific term or key phrase I need to ask a window supplier to get a straight answer?

e.g. one supplier quoted their 'frame' as 33mm thick. Does this mean that for 1066 x 1066 measurements, the glass area will be 1000 x 1000? What about the sill/expansion gap/trickle vents/seals?

 

[Notch7]

Is there a specific term or key phrase I need to ask a window supplier to get a straight answer?

Sightline is the key word.

 

[Tigercubrider]

Can't they supply a sample?

 

[Pete574]

Thanks @Notch7, that term was exactly what I was looking for.
As an example:
http://www.slideandfold.co.uk/sightline-details-for-aluminium-windows.html

 

[Notch7]

This duration link has a download with all the options. -from about page 15.

https://www.duration.co.uk/Smarts-47-Aluminium-Windows-Technical.asp#tabs

The key is distance from edge of frame to edge of sash (opening vent), and the distance from glass to glass at a mullion or transom.