Error while converting into parasolid, house model

Hi solid works users,

I have just started using solidWorks and tried creating a house model in it. I used the different planes and created
surfaced for each wall and roof but now when I try to convert into the
parasolid; it gives an error that 'this kind of geometry can’t be converted
into a solid body’. I am assuming it could be because of following reasons

1. The vertexes and lines are not aligned properly

Questions1.  would
that be possible to combine all the lines and points properly (btw all the
surface have been created in different planes)

1. Is it possible to activate the two or three
   planes together so that points can be matched properly while creating an
   another surface; perpendicular to the existing surface?

1. The final goal is to analyze this house model
   into the Star CCM+ and every room, restroom and lobby has different height that
   why it is kind of hard to use extrude command once, in order to build a frame.
   ( can you please suggest a proper way how to build it, I have just started
   working with Solid works)

Please check the attached screen shot of the model!

Thanks in advance !!

Sandy