Three sided dormer

[charlie.216581]

I have made a dormer with the front face in line with the wall below. I am now trying to remove the roof infront of the dormer just below it. I am doing this because a door will be placed on the dormer wall with a balcony. Can any one help in cutting this part of the roof?

[PijPiwo]

You can modify the footprint of your roof (select the roof->Edit Footprint tool) or use Vertical Opening tool from architectural tab.