Thanks Hans for the second reply....i'm going to add some pictures to explane my "problem"...

http://www.mediafire.com/view/16gk4bs44kof1dd/jp2.png

my house have three levels (bell etage) 0,1 and 2 level 0 is garage, level 1 is the living room and on level 2 are the bedrooms/bathroom so when you are on level 0 you see the stairs that goining to level 1 on the image the stairs is turning below and I would like to change it like on the next picture,turning on top;

http://www.mediafire.com/view/6djh1p47r ... .08.05.jpg
http://www.mediafire.com/view/ufb0dpf4f ... .43.23.jpg

When you go from level 1 to level 2 the stair is turning below and on top how can I change that...?

A other problem you can see on the next picture...how can I add the bevelled edge from the roof to the project and make visible to the 3d view..

http://www.mediafire.com/view/ufb0dpf4f ... .43.23.jpg

and when you look close to the first image you can see I have no floors (vloeren) and seelings (plafonds) how can I fix that..

ok Hans and the others to I hope you can help me to solve this...