The old college try
Engineering Technician
I'm getting ready to install my tub (hopefully tomorrow) and I'm not really excited about the way it feels during a dry fit. When I step in the tub is feels like it sinks slightly before resting on the bottom supports. The instructions say that it should be placed either directly on plywood or if another substrate is used, housewrap material or spunbound landscape fabric should be laid under to prevent squeaking. I'm wondering if I should place it in a bed of mortar with tyvek between the mortar and tub so that it's supported and won't move up and down once installed. This is my first tub installation, so any advice is greatly appreciated.