Some people use the detail or worksheet tools which work OK but are not true live views of the plan.
Personally I don't like that.
Here is a detailed explanation of the way I (and I think many others) do it.
http://archicad-talk.graphisoft.com/viewtopic.php?t=34976
There is another method using a solid white fill that covers your floor plan with a hole in it that exposes the part of the floor plan you want to see enlarged.
Then you need new layers and layer combination for you large scale text and dimensioning (the white fill goes in one of these layers) and you have to juggle the display order to have everything it above or behind the fill depending on what you want to see.
I find the method I use easier.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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