Free-standing acrylic bathtubs

These seem to be a big fad recently-free-standing acrylic tubs… The house is on a slab foundation, this one weighs about 150 pounds, on a tile floor. It’s not secured to the floor, so it slides around with little effort, tethered by a flexible hose for the drain at the left end. The drain is in the center of the tub, then a built-in trap attached to the flexible hose.
The darn thing tips with little effort. 1st - shouldn’t it be fastened or secured to the floor, and 2nd- it seems pretty dangerous to a user taking a bath - if you drop your washcloth over the side and lean over to get it, the whole thing will tip over!

Yes. This is a common oversight on new builds. Call it out. Not only can the tub tip over as you mentioned, but a strong bump to the side can also damage the drain since the drain pipe is the only thing holding that tub in place. drain damage can cause an awful lot of damage to the floor structure.
good catch.

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Not if its full of water.

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Honestly, it’s narrow at the base, and wider at the top… I filled it almost halfway with water and I was able to easily tip it a little bit. I was not able to find any manufacturer’s info for this tub, but most I found say to NOT sit or lean on the edge of the tub as it may tip…

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The free standing bathtubs we have installed have clear directions for proper install. The drain piping is meant to be “flexible”. I don’t like them, personally. I especially don’t care for the fixture next to them as they are difficult to firmly secure on some floor types.
When I see them on an inspection, I am sure to say that I recommend referring to the manual for use and care instructions.

This is a new construction, but it was finished 9 months ago and has been sitting… the builder asking price has been lowered 3x. I have advised the client to ask the seller to secure it according to manufacturer’s recommendations. I don’t like that flexible drain, but it seems to be the only way it can be done. But the tub moving around can’t be good for that drain…

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As an add-on to what’s been stated, I love how all those stalk mounted faucet hand-sprayers leak & dribble on the finished floor instead on inside the tub.

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No flexible drain pipe.
Bathtub must be secured.
The faucet stand must be solidly fastened to the flooring and sturdy to withstand horizontal loading.

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Since nobody else mentioned it yet, there arent any ways to mechanically attach these tubs to the floor. They get attached to the drain, and then a bead of silicone should be applied all around the base. That is the only thing that secures it to the floor, and keeps it from moving or twisting.

As long as it has a nice bead around the base and does not shift when pushing against it, you’re good.

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I encounter freestanding tubs frequently on new construction. IMO they are an expensive problem! Add to that the IRC (Codes) are wholly deficient in proper direction for the installation of these problem units. The IRC over the last two decades has not properly kept up with building and other materials that have even been in use for a decade. It really makes you wonder how they are still around! The IRC section for this is P2705.1.

P2705.1 General. The installation of fixtures shall conform
to the following:

  1. Floor-outlet or floor-mounted fixtures shall be secured to
    the drainage connection and to the floor, where so
    designed, by screws, bolts, washers, nuts and similar fas-
    teners of copper, copper alloy or other corrosion-resis-
    tant material.
  2. Wall-hung fixtures shall be rigidly supported so that
    strain is not transmitted to the plumbing system.
  3. Where fixtures come in contact with walls and floors,
    the contact area shall be water tight.
  4. Plumbing fixtures shall be usable.
    1. Water closets, lavatories and bidets. A water closet,
      lavatory or bidet shall not be set closer than 15 inches
      (381 mm) from its center to any side wall, partition or
      vanity or closer than 30 inches (762 mm) center-to-cen-
      ter between adjacent fixtures. There shall be a clearance
      of not less than 21 inches (533 mm) in front of a water
      closet, lavatory or bidet to any wall, fixture or door.
  5. The location of piping, fixtures or equipment shall not
    interfere with the operation of windows or doors.
  6. In flood hazard areas as established by Table R301.2(1),
    plumbing fixtures shall be located or installed in accor-
    dance with Section R322.1.6.
  7. Integral fixture-fitting mounting surfaces on manufac-
    tured plumbing fixtures or plumbing fixtures constructed
    on site, shall meet the design requirements of ASME
    A112.19.2/CSA B45.1 or ASME A112.19.3/CSA B45.4.

As you see the IRC only definitively requires the base of the tub be sealed around (item 3 above). For securing they weasel out of requiring it by using the phrase “, where so designed,” in item 1 above. Yet if you read other plumbing sections they require support of piping to prevent sagging, movement and damage to the piping and connection points. The ASME standards referenced only deal with the physical construction of the tub itself.

Some manufacturer’s require a bead of adhesive be applied to the bottom of the tub where others not only do not require this but also do not require the floor joint be sealed (amazingly Kohler high dollar tubs are this second category). You can see the IRC does require the base to be sealed.

When I encounter these tubs I do bump them slightly to see if they will move. I encountered one that was so light it could easily be lifted with very little effort. As a result of this these tubs are not only a safety hazard to people but also to the plumbing beneath them. Even if the tub is not in use people are moving around them on a daily basis and can easily bump them in one way or another. If they are not sealed at their base water can penetrate below them and sit taking awhile to dry which as we know can cause mildew, mold, etc. Keep in mind that dust is a good food source for mold.

When I encounter these I do advise the client they need to have the Builder (for new construction) explain how the tub has been secured to the floor and explain the potentials associated with them and that some manufacturers may not require securing them to the floor. If they are not sealed at their base obviously they are written up as per the IRC reference above.

Another issue with these comes when they are installed on the first floor of a slab home. The traps are typically within/below the slab level. They are typically boxed out before pour so the Plumber can make necessary adjustments before setting the tub. Afterward the opening should be fully grouted in as it is exposed to soils below the slab. I encountered one where they did not do that and the bathroom was being invaded BIG TIME by ants who were clearly coming and going from under the tub. The client forced the Builder to remove the tub and sure enough they did not grout it in.

It is important for the client’s protection that they understand how these tubs are installed and the potentials for not having a safe and proper installation. Since you have no idea how they were installed it is safer for the client and yourself (problems later) to report on them. Make sure it’s in writing so there is no question later!

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Thanks for your input… thankfully, the client was present and saw this. Thanks to the tile floor, I could literally push this tub with 1 finger across the floor till it was 90 degrees from its original position, and the client and I were easily able to lift it to see the connection to the drain. He saw how easy it was to tip. It looks amazing when you want to sell a house, but I can’t imagine having one of these in my house.