Does anyone use an Expedit for dividing a room and therefore not anchoring it to the wall? We are thinking of getting a 5x5 and a 4x2 and using them as toy storage in the basement and it would become a "wall" to divide the kid area to the storage area. No wall behind them to anchor them to and concrete on the sides.

Is this safe or should we figure a way to keep it from tipping? The 5x5 is the one we're worried about. The 4x2 would be horizontal and only 2 high.