Mortar Bed or felt pad & shims for Vikrell Tub & Wall ensemble?

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RickFlorida

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Hi everyone,

I have a new Kholer/Sterling tub and walll ensemble kit (made of that Vikrell stuff). My floors are solid old Terrazo (old Florida home). Should I install the tub with a mortar bed to level it or could I use a felt pad and shims?
I imagine the Mortar bed would actually make it easier to level in one sense because I could push down and get it right and let it set. However, I'm afraid that since it's really tricky to install the tub drain assembly since I have zero access below the floor (Up North, people have an easy time installing tub drains because they can access the drain to tub from basement or floor below), I am a little worried that I need more room for error with getting the drain in right and will get messy. Is there a premium felt pad material I could find and then use shims?

While we are on the subject, what is the trick in getting the drain assembly on correctly when you have no access below? I suppose connect as much of the drain assembly to the tub first as I can before lowering the tub down?
Is there a kit that is better than others for having no access?

I'm a school teacher so I just don't have the money to pay for a professional install. The prices here in Florida are absolutely astronomical right now. My small bathroom quotes would be over 15,000 for remodels.

Thanks,
Rick
 
Set in a mortar bed makes for a solid install. I use cement sand mix, and use a good bit of water to make it soupy.
 
Set in a mortar bed makes for a solid install. I use cement sand mix, and uses good bit of water to make it soupy.

Yeah, I did read that it will help "quiet the movement" of an acrylic tub like this so I should probably do it. But how do I make sure I can connect the drain kit to the tub smoothly since I have zero access to it once the tub is lowered. Do I connect everything I can do the tub first? Is there a premium tub drain kit that "snaps" together at some point when I lower the tub down? It's going to get real messy and troublesome if I have the wet mortar bed and then lower the tub and then have trouble connecting the drain.
 
I consider myself very handy, but setting a tub in a bed of mortar, while properly securing the drain, should be left to the professionals. You have one chance to get it right, and this is something the professionals know about. This is just my honest opinion.
 
I consider myself very handy, but setting a tub in a bed of mortar, while properly securing the drain, should be left to the professionals. You have one chance to get it right, and this is something the professionals know about. This is just my honest opinion.

Hmmmm. You are probably correct to say this for most people. But I have installed toilets, repaired many copper pipes and their valves, etc. I'm a fast learner and good at most any home project you can think of. I removed the old tub and know how the parts work. However.... I have not myself installed a tub. But is there an easy trick? Professionals often just know the easy trick to make it simple For example...... the trick to installing a toilet with the wax seal is to stick the wax seal on the bottom of the toilet first before lowering the toilet down. If a new person tries to put the wax seal on the flange first and then lower the toilet seat, this results in the wax seal getting destroyed more often then not.

I believe if a professional simply tells me how they install tub drain kits when it's a terrazo floor (no access below like up North), then I could do it. My best guess is that I have half of the connections done on the tub and the drain pipe in the ground done and then "slip" or "snap" the two together.

This is not a 400 pound cast iron tub. It's a super light acrylic tub. I also wonder if there is a tub drain kit that has more user friendly than others?
 
Sorry to answer my own question but I found the solution which I knew in my heart something like this must have existed. To make it very east to drop tubs down onto drains there is a "slip in" system. One of them is the Jacuzzi MZ-20000 (Island Tub Drain) . Here is a video on how it works.
So professionals know how to make this job easy if they simply purchase this "slip" in drain system for tubs. Hopefully my question here helps others.

I'm not sure I really need this but perhaps this is an option I should consider.

The kit is a ridiculous 228 dollars but that is way cheaper than 15,000 dollars which is the minimum bath remodel quote here in Florida right now.

Does anyone know if there are other "slip in" drain kits besides this Jacuzzi branded one?

A video on how to use it:
 
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Just installed pretty much the exact same thing, BUT my bathroom has a 16" square access door where the drain is located. I don't know the plumbing codes for your area but having a bath drain completely inaccessible seems odd to me. Any chance you can access it through the wall where the drain is located (i.e. cut a hole in the drywall from the opposite side of the adjoining room/wall?)
I spent a looong time dry-fitting and checking/re-checking my drain setup before setting the tub into the mortar to be sure the drain would fit exactly. But I was able to do the final glue joint after setting the tub thanks to that small access door
 
Just installed pretty much the exact same thing, BUT my bathroom has a 16" square access door where the drain is located. I don't know the plumbing codes for your area but having a bath drain completely inaccessible seems odd to me. Any chance you can access it through the wall where the drain is located (i.e. cut a hole in the drywall from the opposite side of the adjoining room/wall?)
I spent a looong time dry-fitting and checking/re-checking my drain setup before setting the tub into the mortar to be sure the drain would fit exactly. But I was able to do the final glue joint after setting the tub thanks to that small access door

What I mean by "no access" is that my house is a single floor ranch style house in Florida. So unlike up North where it seems people can access the drain from below when they connect it (either from basement or 1rst floor), we have to set tubs down in Terrazo floor "blindly". There is a wall though of course and perhaps I can reach a little from the other side which is my Kitchen. But the wall would be inside the cabinet. Is that what you mean?

By the way, here is a photo. When I look down the drain I see water which means it has a P trap below the slab. Does this mean I need a trap adapter for the drain connections?
 

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Yes I was jealous of those North/East Coast homes where under floor access was available..! Saw them on plenty of videos - so easy....
You understood my suggestion re: access, but from your pic it looks like you have too many pipes in the common wall space to be able to access the drain from the other side of the wall. the kitchen cabinets would make it more difficult too....
If you see water, the P-trap is indeed probably under the floor... :(. Mine was 2 feet below the bath level pretty much in the ceiling/wall space of the room below which was awkward for me...

My suggestion. I did this with mine and it helped a lot....
You could use a piece of cardboard on the floor as a template. i.e. tape down the cardboard and then put the bath in place and trace the tub drain hole location onto the cardboard, then remove the tub. Then you have the position that you need the drain to be located to exactly match the tub drain hole.... then you just have to figure out how high above the floor level it needs to sit and figure out the overflow connection pipe.
I suggest you 'creep up on it' by dry-assembling the pipe/drain assembly and checking it by putting the bath back in position multiple times and adjsting it until you're sure it fits exactly. Then glue the piping, check fit the tub one final time and if all is OK place the mortar and fix the tub in position.
Good luck !
 
PS: if you have a P-trap under the floor you only need a tub drain kit like the below. Not sure what you mean by a trap adaptor but you should use a glue type adaptor to attach your tub drain above the P-trap. Since you cant access it after the tub is in place I'd recommend gluing and also pour water down the drain assembly to test for leaks before putting the tub in place.
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oh - and put a ton of silicone either side of the gasket and around the flange of the drain when you do the final install of the drain into the tub hole. Better than using plumber's putty in my experience. OK....I think that's enough from me now... !
BTW please note that I'm not a plumbing professional. I'm a long-time homeowner/DIY'er with recent experience of this situation. I defer to others on this forum for technical details, code questions etc...
 
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Slip joints are not allowed in inaccessible locations. Glue joint is the only waste and overflow allowed.
We NEVER use an island freestanding tub drain for a drop in tub.
We make up the glue joint w/o assembly and dry fit while the tub is out of the alcove. Then, set the w/o and dry fit the tub to check for alignment.
When everything is perfect, we do the mortar and drop in for final assembly.
I highly recommend hiring a good plumbing contractor for this.
 
Thanks for the comment breplum.
In fact the drain pic I pasted was misleading. I've updated my comment & pic to the type I used (ABS & glue)
 
I wanted to update this in case others need help. The pro's here were right that you don't need slip joint for the drain. What I did was simply design the whole overflow connection to tub first, then attach the whole thing to my copper drain pipe in the floor. Then, I put the tub in position and was able to simply screw in the tub drain and overflow. I did have some access through a panel. Not much access but just enough to push the overflow against the tub so the screws would connect. I also created a mortar bed with thinset. I used one 50 pound bag and put it in the middle. It allowed me to not only make a more solid install, but it helps you to level the bathtub easier instead of leveling the entire floor with an expensive floor leveler. My floor was already close to level so the mortar bed was fine.
 

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Update: It passed all tests I through at it. The tub is surprisingly solid from just using the 50 pound thinset mortar bed. I don't know how anyone could install these without an access panel though. I assume they reach their hand down under the lip of the tub and push the overflow pipe against the wall of the tub to screw it in. What really amazes me is that professionals can install 300 to 600 pound cast iron tubs in these small spaces and with little to no access. This is just a light acrylic tub that I could manage as a non professional.
 
The only time I installed tubs without access from the back was in apartments or condos. Usually those were cheap steel tubs or fiberglass.
 
The only time I installed tubs without access from the back was in apartments or condos. Usually those were cheap steel tubs or fiberglass.
But do you have a trick or tip for how to start the screwing in of the overflow to the drain assembly when you have no access panel? My brother is about to install a tub like mine with same situation (Terrazzo floor, no basement) but he has no access panel like I did which I used to push in the overflow tube against the tub to start the screwing in process. I think he can reach his hand under the but since the wall would not be in yet, correct? My install went perfect and was easier than I stressed about.
 
I would measure and pre install my tub waste. You have to be accurate.🤓
 

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