General Note: Please allow 24 – 72 hours for your Mattress to regain its full shape. Any memory foam will expand faster in a warmer room. In cold temperature, at delivery, your mattress may take a bit longer to return to full sized from its compressed state. The expansion time of the mattress will vary as per the surrounding. General Note: Please allow 24 – 72 hours for your Mattress to regain its full shape. Any memory foam will expand faster in a warmer room. In cold temperature, at delivery, your mattress may take a bit longer to return to full sized from its compressed state. The expansion time of the mattress will vary as per the surrounding.