Do I place the Purple™ Powerbase on an existing foundation? This PowerBase has been retired. For information on our new adjustable bases, click HERE. You want to place the Purple™ Powerbase directly on the floor. Related articles What mattress foundation should I use? What is the weight limit for the Purple™ PowerBase? How far apart can the slats be on my foundation or base? Can I put the Purple® Mattress on the floor? How does the zero clearance feature work?