Pankaj, I just realized that initially you told us that the bathroom area was 12'-0" x 9'-0" and later you mentioned that it was 11'-8" x 8'-0". In the last floor plan, I forgot to change the bathroom with the new dimensions. Below is the floor plan with the correct dimensions for the bathroom. The bedroom is ok, I drew it 19'-2" x 12'-6". The new layout does not change the way things are placed. Everything still fit. The only difference is that the vanity is now 4'-4" long instead of 4'-8". and the toilet is closer to the shower by 1'-0". Can you give me the lengths of the walls K and L. They are the walls between the vanity and the shower area. I will send you the new layout once you give me the length of these 2 walls.

Upholstery and egg crate type foams will not be rigid, and may not be flame retardant. EPS and XPS construction insulation foam are lighter weight, more rigid, and could be covered with batting and fabric. They come in 4'x8' sheets, but can be cut with a utility knife into smaller sizes. They are available from a big box home improvement store like HD or Lowes. Not sure if they are flame retardant. Depending on how large a piece you are mounting, I would think they may be light enough in weight that they could be mounted to the wall with 3M removeable hangers of some sort.

An architect would be the best person to ask. Hard to envisage without pictures. Posted July 2014 - do you still need help?

Normally the beams would help define each space.