Is a cast iron tub ok sitting on top of pressure treated wood?

Yes, a cast iron tub can be placed on pressure-treated wood, but it's essential to ensure the wood is adequately supported and level to prevent cracking or damage to the tub. Additionally, the pressure-treated wood should be allowed to dry out and cure before installation to avoid moisture issues. It's advisable to use a moisture barrier between the wood and the tub to protect against any potential water damage.