creating a boundary with holes in it

Hey guys,

Quite a basic question i should think but I'm a bit of a novice -

I want to create a boundary with a 'hole' in it - this actually takes the form of a large wall polyline boundary that I want to 'subtract' a bunch of window polyline boundaries from..

I've tried using BHATCH to hatch in the area i want and this works fine, but when I click recreate boundaries to get the resultant boundary (wall with windows cut out) i get seperate boundaries again - ie the large wall and the seperate windows.

any ideas?

Would REGIONS be more appropriate in this situation?

You could explore the GROUP command, it groups together lines to form a half-way-block sort of. Depends on how you want to use it later though...

Are you using the plines with a thickness to give impression of a wall if so can not subtract a hole, but you can receate the wall made up of smaller bits (left of hole, under hole and above hole, right of hole) to give illusion of a hole when viewed in 3d, else extrude and subtract.