Can A Bathtub Fall Through the Floor? (7 Causes, 3 Preventative Measures)

The fear of a bathtub falling through the floor is real. People actually do fall in family rooms with their bathtubs. The CDC (Center for Disease Control and Prevention) reported that falling tubs are among the top causes of bathroom and toilet accidents in the United Statesabout 235,000 people aged over 15 years are injured in the bathroom every year.

Towards the end of 2019, a family in Bronx, New York, was petrified when their bathtub hurtled down the floor with their 4-year old daughter in it – she survived in one piece.

Still in New York, two plumbers were sent flying into the basement after the floor bungled under the weight of the tub they were trying to install.

Cases like these are rare but dreadful enough to leave you pondering.

While the odds of such accidents happening are very small, their causative factors are ever-present – it just takes the right mix of these factors for the floor to cave in under the weight of the bathtub.

The most frightening thing, however, is that you do stand a sizeable chance of bungling down the ceiling in with your tub.

What Are The Causes?

What might cause the bathtub to fall through the floor? He is a list of the causative factors:

1. Natural aging of the floor

The older your home is, the riskier it would be to install a bathtub anywhere on the top floor. The materials that make up your floor tend to weaken with time and will reach a sagging point that might not be easily noticeable until it’s too late.

The rate of aging can depend on a range of factors including whether you carried some cosmetic changes to the structure at some point.

Even if you didn’t perform repairs at all, the floor will still age and start leaking or showing cracks as the materials weaken. In fact, leaking is one clear indicator that your floor has seen better days.

Repair the floor immediately you spot cracks or other flaws in the structure of your floor.

Consider dismantling the bathtub, the toilet, and other heavy items already installed on the floor.

2. Flooded floor

Allowing pools of water to collect on the floor causes the floor parts to rot or weaken, Water can break down the flooring glue and rot the plywood and any other wooden structure, eventually causing the floor to develop weak points.

Water does weaken concrete floors just as easily as it does on wood-based floors, it just needs to remain standing on the floor for a sufficient amount of time.

Minor accumulation of moisture on the inner parts of the wall can cause extensive rotting in the long run as well.

Installing a bathtub on a moist floor is one of the riskiest things you can ever do in the bathroom. Once the water has damaged the floor to a breaking point, falling with your bathtub becomes a question of when, not how.

3. Installation flaws

The maker of your home might have made mistakes during the construction.

1. An uneven floor is one of the common problems that come with hastily installed floors.

2. Another error is inadequate preparation or clearing of the surface meant to hold the floor.

3. Yet another common installation mistake is installing the floor in the wrong environment. If the builder laid the hardwood in damp conditions, especially if your home is situated on a cold and high humidity climate, the wood will warp during the drying process.

If the maker didn’t observe the stringent requirements regarding the evenness and thickness of the floor and even the quality of the materials, the floor might develop problems in the future.

If, for example, you installed a heavy alcove bathtub on the weakest section of a badly installed floor, you would’ve exposed yourself to the risk of falling through the floor with the tub.

Hardwood floors are especially reliant on the subfloor because they are prone to contraction and expansion. So, if the subfloor is not even enough or the builder didn’t attach it to the hardwood properly, the floor will likely buckle down.

It would be prudent to ascertain that the floor was installed per the acceptable standards before buying the home.

4. Previous damage

Do not install a bathtub on a floor that previously sustained considerable damage from fire, impact-induced cracking, or drilling.

Previous damages may have left flaws on the floor which might not be easily observable during a simple inspection.

If you install a bathtub without understanding these damages, you will be setting up just the right environment for the collapse of the entire floor.

5. Non-conformity with building regulations

Local building codes will recommend the specific thickness of the floor beyond which it would be dangerously thin to support household weight or too thick to be adequately supported by the structure of the home.

The local authority may also recommend specific materials that should be used and flag certain materials as inappropriate. There is usually a reason behind every directive.

If the contractor goes ahead to flaunt these regulations, there is a likelihood you will end with a substandard dangerous floor – basically, nothing short of a death trap.

6. Overloading

Your floor has weight limits that must be considered when installing home equipment.

The weight of most household items falls within the margins of what the floor was designed to support comfortably.

Also, floors are often constructed for a purpose.

For example, the floor of an office building would be stronger than that of a residential building because it needs to support several office equipment and more people per given dimension.

However, one of the major causes of floor failure in residential has something to do with overloading.

If you pile several items in your bathroom, the integrity of the floor will be compromised. For instance, there is no good reason for installing two bathtubs or a bathtub and a bunch of cabinets and other items you don’t even need.

How Do You Prevent the Bathtub from Falling Through the Floor? 3 Ways….

The trick to avoiding bathtub fallout is to never install a bathtub upstairs in the first place. This is especially advisable if you live in a manufactured home for such homes are made from assembled parts.

Concrete floors are good for installing a bathtub, but that doesn’t mean they are foolproof. Whether you live in a manufactured home or site-built home, avoid a bathtub fallout by taking these precautions:

1. Avoid major alteration to your floor

Your floor should remain the same as the builder left it.

Floor alteration is one of the major causes of cave-ins and other floor problems.

The builder will construct a “tailor-made” floor that works perfectly with the general structure of your home to preserve the integrity of the whole home.

When making changes on the floor, however, you may not be privy to the support features of the home and even the capacity calibrations of the floor. If the floor is damaged, consider repairing, not modifying it.

2. Correct positioning of the bathtub

Do not install the bathtub just anywhere in the bathroom. Rather, figure out the direction the floor joists run. Then ensure that your heavy bathtub or any other accompanying “bathware” spans multiple joists.

Remember, the joists are the backbone of the floor, they support much of the weight of the floor structure as well as everything placed on it.

So, installing a bathtub on the position of joists means the backbone of the floor will support most of the weight.

This can be the best approach for you if some parts of your floor underwent repair work recently – as long as the joists are in great condition, you’re good to put all the weight on them.

But that’s still going to depend on the strength of the joists where they join the walls and the rest of the home’s support beams. If those areas are weakened, you’d rather not install the bathtub.

3. Keep the floor dry

As we mentioned earlier, pools of water can ruin your floor just as quickly as a full-blown demolition exercise. If your floor is made of wooden parts, allowing flooding is the worst thing you could ever do because the wood will rot and disintegrate in the glued and bolted areas eventually causing the floor to lose its integrity.


The thought of a bathtub hurtling down through the floor is one of the most frightening things you can imagine at home. It can happen. Most of the causes of the falling bathtub have something to do with the integrity of the floor.

If the floor was poorly constructed or the builder didn’t observe the local building standards, there is a strong chance it will crumble under the pressure of any heavy installation such as a bathtub.

You can prevent the bathtub from falling by avoiding to modify the floor and protecting it from flooding. Also, ensure that the builder of your home observed all the required building standards when constructing your home. Also, avoid overloading your bathroom’s floor with installations you don’t even need.