Hmmm... Most buildings usually have flat walls, so you would expect one of the 3 coordinates to remain consistent, either on the x,y or z axis depending on whether you're defining a wall (and which wall you're defining), floor or ceiling.

So in this case it looks to me like the y axis is more or less consistent so I changed it to:

Code:

beginShape();
  vertex(-15, -40, 40); 
  vertex(25, -40, 20);
  vertex(35, -40, 110); 
  vertex(130, -40, 90);
  vertex(110, -40, 5);
  vertex(80, -40, 5);
  vertex(85, -40, 65);
  vertex(65, -40, 70);
  vertex(50, -40, -10);
  vertex(-20, -40, 10);
endShape(); 

...and I get a nice flat shape that renders properly

When you're filling a shape in 3D you have to ensure it's a flat plane otherwise you see the rendering errors you experienced before.  With your building that should be easy enough as long as you ensure one axis is consistent - i.e. your walls are flat.  If you need to create curved shapes you'll have to break them down into triangles.

Obviously your wall looks a bit wonky at the moment.  I'd suggest mapping your building out on graph paper first: that should make it much easier to plug in the right coordinates to your vertices

Fantastic, I didnt realise anyone had got back to me on this one, thanks both for your help, I can finaly revisit my sketch!