Cast Iron Tub Install, PLEASE HELP??

chipraynor

I am installing a kohler cast iron whirlpool tub.

My current bath is new...2x10's under 3/4 tongue and grove Advantech (better plywood material (main floor). Hardibacker ¼ subfloor prepped for tile.

This tub is heavy!! 300 empty. I was looking to build an island style box. Adding a ½ plywood floor, 2x4 walls, ½ plywood top, then ¼ hardi for tile on top and around side of the tub. IS THAT OVERKILL?

Reading kohler recommends splitting the framing/surround due to its weight.

My thoughts building a box, having the 4 feet rest on the ½ plywood, then setting on the ¾ main floor would be better then it just resting on the Advantech. I also though having a island style I could remove the grout lines and pull the box out if needed then trying to remove sides of the wall of the tub.

The location is in the corner, so I would be building a knee wall in the front and on 1 side if I didn’t do the island….

ANY THOUGHTS,
Thanks

tub...
http://www.us.kohler.com/onlinecatal.../1019700_4.pdf

Just Bill

The place to build boxes, IMHO, is on the house framing. Double up the floor joists under the tub/feet area and run supports between the joists. Those 4 points support all the weight.

Total weight witout a body is 770lbs, in a 3'x5' space(about 52lb/sf), design for that. Most house framing will hold 40lb/sf with no changes.