Pentominostreet

Thanks to Andreas Rottler (Germany) for the idea of our new challenge.

Use a full set of pentominoes (see picture)

to make a street, in such a way that the area of the rectangle, which is formed by drawing the vertical and the horizontal line at the ends of the street, is maximized.
The pentominoes have to be in one plane, and touch by a full sidelength of a unitsquare (point or corner connection isnít enough).
Both parts of the rectangle, that is being divided by the pentominostreet, have to be one part (no internal holes) and have the same area.
Look at the example below to have a better understanding of the challenge.