i removed old steel tub. relacing with cast iron tub. do i need to reinforce the floor joist?

Answer 1

I went over all my joists and when installing a tub in an older home, I put down up to 150 pounds of" level set" and set the tun into this, make sure everything is lined up and ready for hook up first.

I checked all the joists, some were bad and I put in new ones. Then I laid down a 3/4 inch sheet of treated plywood, on this, after lining up the tub for installation, I put in 150 pounds of level set then put the tub directly into this and, made sure everything was hooked up and ready to go, then continued the hook up.
The tub is well set in, doesn't make noise.

Answer 2

If you had added a few details the answer might be more helpful, no offense.

Is the floor, on which the tub sits accessable from underneath it? IE: Basement/Crawl Space/Living area as in first floor?

Is the Cast Iron tub sufficiently more weighty than the steel tub? Is it a claw foot by chance?

Reinforcing won't have as much effect in just adding to the joists as having it supported by verticle supports, or if it's already being supported by load bearing walls, I see no issue.

Also,and just my opinion, I wouldn't "Float" any substance, then set any tub into it. At some point the REMOVAL might be an issue, and certainly would need remediation after the fact. Adding any subfloor over the existing subfloor might not hurt, but also might not strictly be neccesary.

As I said; and with all due respect; a few more details might have aided us in answering.

Steven Wolf

Answer 3

If you can access the joists, it would be good to check them for cracks or other deterioration. If the tub is not a clawfoot, you should have no problem since the tub will be setting on more than one joist. A mortarbed is not normally needed under a cast iron tub. Under fiberglass and plastic tubs, a mortarbed will stop stress cracks by supporting the bottom of the tub.

Answer 4

the tub could be fastened by a couple of ways 1. if it has molding around it, check and see if they used tapcon srews on it. 2. if there is no tapcons then they might have use a glue to fasten it in. You will have to cut the glue out usind a recepcating saw (or someother item to cut the glue) 3. they could have use cutter nails(horse shoe nails) With it being a cinterblock wall the pluming will be tricky to say how they ran it with out looking at it but the main thing on the drain is to measure the dist. from the walls and make sure you get a tub that has the same measurements. I hope this helps If you post a pic i might be able to give you some more help or you can email me a pic. as far as the drain you can build a platform so you can rerun the drain to fit a new tub.

Answer 5

You do not mention the weight differential and how the floor joist looks right now. Considering they are equal you should be fine. If you are talking about an old cast iron tub on legs, it's irrelevant because the weight will be absorbed on the 4 legs.

Answer 6

maybe.