Walk-in tubs usually need a bigger space than your average tub. Not only is the bathtub itself bigger, most handicapped seniors also need enough space in the bathroom for easy access with a wheelchair.
Some of these mobility tubs are designed exactly with a small bathroom in mind.
An elderly person that has a small bathroom can fall and break bones as easily as one who has a big bathroom.
When looking to fit a walk-in tub in a small cavity or alcove, we have to look for a small and compact bathtub that has appropriate features to fit in such a small space.
There are 3 main features when looking for the best safety tub for a small bathtub:
The tub itself should be small. Rectangular or cube tubs are usually the best.
Inward swing door. Most bathtubs for the elderly have a door that opens outward. If you lack the space, an inward swinging door is perfect.
No fancy features like hydro or air jets. Installation-wise, every kind of jet needs additional motor and electricity that has to go somewhere. The installer has to break additional tiles, make tile flanges and all this is a smaller amount of space.
In short, if you have a small bathroom, keep in mind to look for a step-in bathtub that is:
Small. With an inward swinging door. Simple.
Dimensions Of The Smallest Walk-In Bathtubs
Dimensions of a standard bathtub with doors for elderly is very similar to the size of an ordinary tub.
It has a capacity of about 60 gallons, with dimensions of 32” x 52” x 38” (width x length x height).
Chances are that you’ll hardly find a walk-in tub with a width below 32”. Opting for 28” width in the best you can do.
Where can you really save space?
Reducing those 52” of handicap tub length is something you can do. If you look around for a small walk-in tub, you’ll see that you can find one with a length of about 38”. That saves more than a foot of space in the bathroom.
Finding the smallest walk-in bathtub for seniors will also save you money when it comes to the installation. The number of tiles installers will have to break will be reduced by more than 20% if you go for a rectangular tub.
Height, on the other hand, the height doesn’t really need to be reduced. The height of the small and bathroom are usually the same. In fact, choosing a small tub but the deeper walk-in tub will give an elder more space in the bathtub. The number of square feet you dedicate to a tub, however, will be minimum.
Rectangular walk-in tub shown below by Meditub is a perfect example of a tub that can fit in a small bathroom:
Meditub rectangular tub is only 38” in length. It occupies more than 25% less space than a standard walk-in tub.
Inward Swinging Door
Most of the standard-size and bigger accessible tubs have an outward swinging door. That can be convenient for a bigger bathroom, but if you lack space in the bathroom, every square foot counts.
One of the best features is the inward swinging doors. The bathtub door simply swings inwards instead of outwards.
That frees quite a lot of space in front of the walk-in tub but it doesn’t impede on the ability to have an enjoyable bath. Given that door itself can be 15” wide, it really is impossible to install a bathtub if bathroom space is scarce. This is especially useful if you have a narrow bathroom.
Not many producers offer inward swing doors for their sitting tubs but it is quite important that such doors are included in the design of the smallest walk-in tub.
Here is an example of an accessible tub by Ella. It’s nicknamed ‘Petite’ tub because it is very slim – only 28” wide – and can easily fit in a narrow bathroom:
Petite soaking tub with an inward swing door. Only 28” wide and perfect for a narrow bathroom.
»Fancy« Features Only Make A Tub Bigger
A lot of sit down tubs feature different add-ons such a hydrotherapy and aromatherapy. Those don’t add to the protection of the elderly but they do make installation more complicated and require additional space.
All the hydro and air jets have to go somewhere in or underneath the bathtub, adding to its size and increasing the space required for a walk-in bathtub.
Of course, they are also more expensive than smaller tubs. A high-quality hydrotherapy walk-in tub can set you back $10,000 while you’ll easily find a simple and compact one for less than $5,000.
For basic taking-a-bath functionality for seniors, one does not need to spend that much space or money.
The best smallest walk-in tubs have a simple design and should neatly fit in the smallest bathroom alcove.
Here is quite an extraordinary example of 29.5” wide Ella Deluxe tub that is both very simple in design and it features an inward swing door. This is an example of an almost perfect small walk-in tub that is also affordable:
Ella Deluxe bathtub is simple and easy to install. It also has an inward swing door and a price tag of less than $3,000.
After enjoying a bath in a walk-in tub, we can’t just open the tub door. These safety tubs are special; a senior has to wait for the walk-in bathtub to drain.
How fast does a walk-in tub drain?
It can take up to more than 10 minutes for all the water to go out of the tub. The fastest draining walk-in tubs, however, can be completely emptied in under 120 seconds.
We’ll give you an example of a fast-draining accessible tub further on; however, keep in mind that how fast does a walk-in tub drain depend on 4 factors:
The capacity of the walk-in tub.
Water pressure in your pipes.
The width of your water pipes (3/4 inch pipes are preferable to 1/2 inch ones).
Does the walk-in bathtub have specially designed water pumps to pump out water? (Only the fastest draining walk-in bathtubs include those)
Normal piping and a standard walk-in tub capacity of 60 gallons should drain the bathtub in about 5-10 minutes.
Walk-In Tub Draining Times
Depending on how quickly does the walk-in bathtub empty (or in other words – how long you have to wait in the safe step tub to be able to open the bathtub door), we can put accessible tubs in 4 categories.
Later on, we’ll give you 3 examples of the fastest draining tubs (under 2 minutes).
Here are the 4 rough draining times for walk-in bathtubs:
Super Fast Draining – 1-2 minutes. Bathtub comes with 2 draining holes/pipes and possibly a drain pump system.
Fast Draining – 2-6 minutes. Has 2 draining pipes but no drain pump system. Usually smaller tubs below with 50-gallon capacity or less.
Average Draining time – 6-10 minutes. Only has 2 two inch draining pipe. This is the standard draining time of walk-in tubs.
Slow Draining – 10-15 minutes. Only for very large walk-in tubs like the barometric tub and if you have low water pressure in the piping.
These estimates of how much time it takes for a tub to empty are exactly that: estimates.
Every walk-in tub has it’s own particular drainage time that is usually specified in its description.
If you would like for a walk-in bathtub to have a fast draining system, look for the ones with 2 draining pipes and a full drain pump system.
Top 3 Fastest Draining Safety Tubs
We’ve found 3 examples of the fastest draining tubs in order for you to have a look at the main features that enable them such record drainage times.
#1 American Standard 30″ x 52″ Tub – 2 Drains and Quick Drain TechnologyAmerican Standard has developed a patented Quick Drain technology that enables super fast drainage of their bathtubs.
The 30” x 52” model shown below has implemented this technology marvelously:
This American Standard walk-in tub will drain in less than 2 minutes.
Thanks to the QUICK DRAIN patented technology, American Standard tubs have a bit on an edge when it comes to how quickly their walk-in tubs are drained.
#2 Ella HM3117-HB Royal Tub – Drains In 80 Seconds
The Royal Tub by Ella is one of the classic walk-in tubs that excels with record-breaking drainage times.
The big dual 2-inch drainage pipes are top-notch when it comes to gulping gallons of water per minute. If you have ideal piping (pressure, volume, cross-sections), Ella claims that this safety bathtub can drain in less than 90 seconds:
Some Ella tubs like this one can empty in less than 90 seconds (with perfect piping).
Ella tubs have, in general, one of the most recognizable designs of walk-in tubs.
#3 MediTub MT3053RWD Standard Fit – Empties In Less Than 60 Seconds?
MediTub’s great advantage is their Auto Drain technology that promises to drain a walk-in tub in less than 60 seconds.
60 seconds might be a long shot but there is no doubt that because of Auto Drain technology, MediTub bathtubs are one of the fastest draining tubs. Here is the well-known MediTub Standard Fit model:
MediTub Standard Fit bathtub with Auto Drain technology.
One of the best way to safe haven a senior citizen in their own home is to buy a walk-in bathtub. The tubs themselves are expensive but in the long run, we have to think about how much water does it take to fill up a walk-in tub and how this is going to impact your water and electricity bill. Does water to fill a walk-in bathtub cost 1$, 10$ or 100$? Not to mention that you’ll also probably have to upgrade your water heater.
You don’t want to spend $10,000 on a new walk-in tub only to find out you don’t have a big enough water heater, right?
A walk-in tub water capacity is anywhere between 40 and 120 gallons (as you can see from the table below), depending on which type of walk-in bathtub you’re looking for:
Type Of Walk-In Tubs
Dimensions (W x L x H)
Est. Water Capacity
Standard Size Walk-In Tub
30” x 52” x 38”
50 gallons
Deep Tub (Soaker)
30” x 52” x 46”
80 gallons
Bariatric Walk-In Tub (Over 300 Pounds)
40” x 52” x 38”
100 gallons
Long Walk-In Tub
30” x 60” x 38”
70 gallons
Long And Wide Tub
36” x 60” x 38”
90 gallons
Rectangular Walk-in Tub
32” x 38” x 36”
40 gallons
Two-Seater
36” x 80” x 38”
120 gallons
According to Home Water Works organization, we use less than 20 gallons of water for a regular shower. Do you know how many gallons of water does it take to fill up a walk-in tub? The biggest tubs have a 100-gallon capacity; that is more than 5 times as much water used than for a normal shower. Pretty much nobody has a 100-gallon water heater already installed at home.
The amount of water we use to completely fill a walk-in bathtub depends on the walk-in tub dimensions. The average water capacity of an accessible walk-in tub is typically 60 gallons (according to MySeniorSource) but this number is merely a rough estimate.
We have added the measurements with the walk-in tub types but it is recommended that you open our article about Walk-In Tub Dimensions here to better understand what particular walk-in tub we’re talking about.
Below we’ll list how much water you need per bath given the 7 most common walk-in tub types and give you some concrete examples of walk-in tubs and water heaters to use with them. Furthermore, we’ll try to roughly estimate how much your monthly water and electricity bill might be affected if you decide to use a particular walk-in tub on the daily basis.
How Many Gallons Of Water Does Walk-In Bathtub Hold?
Every walk-in tub model has a certain water capacity (usually found in the specifications). If you think the amount of water a walk-in bathtub can hold is not all that important, we implore you to think about the following:
Do you have a big enough water heater to fully fill your walk-in tub? If you have a 60-gallon tub and only 40-gallon water heater, you’ll have to upgrade it.
How much does it cost to fill the tub with hot water? Considering the water and electricity (for heating up water) prices, you’ll pay much more for a let’s say 100-gallon tub.
How long will it take for a walk-in tub to fill up? According to Hunker, the average bathtub faucet water flow is about 5-gallons per minute. That means that it will take 10 minutes to fully fill a 50-gallon walk-in bathtub and 20 minutes for a 100-gallon tub (the flow for walk-in tubs is usually much higher if you upgrade 1/2 inch pipes with 3/4 inch pipes).
We’re going to list how much water you need to fill walk-in tubs of various dimensions according to the water capacity found in the specification. However, before we look at the numbers, be aware of two crucial things that determine how many gallons of water you really need for a walk-in tub:
Body water displacement – this is the amount of water your body displaces when you’re enjoying a bath. For example, if the full water capacity of a walk-in tub is 60 gallons, you will require 60 gallons of water to fill a completely empty tub. However, if you’re sitting in the tub, you won’t need so much water because your body fills the tub as well. According to a quick calculation, the body of a 200-pound individual (fully submerged) accounts for 24 gallons of water. That means you’ll only need 36 gallons of water to fill a walk-in tub.
Filling a walk-in tub to the brim – the water capacity from the specifications tell you how much water you need to normally fill a walk-in tub. However, you can pour even more water in and if you fill the tub to the brim, you’ll need some extra gallons of water. Carol Bluestein tells a great story about how she could fit 70 gallons of water in her otherwise 50-gallon walk-in tub by filling it up to the overflow outlet.
In short, you can easily subtract 20 gallons of water from the walk-in tub capacity because of body water displacement and, on the other hand, add about 20 gallons if you want to fill a walk-in tub up to the overflow outlet.
Water Capacity Of 7 Most Common Walk-In Tub Types
Below is the list of walk-in tub types and how many gallons of water you need to fill them.
Rectangular walk-in tub requires only 40 gallons of water.
The best thing to do when trying to figure out exactly how much walk-in tub water expenditure you can expect is to directly contact the distributors. They can readily help you with all your concerns, and some of them even give you a rough estimate of how many gallons of water their walk-in tubs require. Here are two examples:
TheraTub – one of their newest walk-in tubs holds as little as 47 gallons of water.
As you can see from the walk-in tub water capacity list several types of tub even come close to 100 gallons of water for a full bath.
Water Heater Powerful Enough To Fill A Walk-In Tub
100-gallon water heater upgrade for walk-in tubs with higher water capacity.
Most households have a 40-60 gallon sized water heater. This is usually enough to take our needs for clothes washing, dishwashing and showering. However, a walk-in tub presents a big drain on the water heater and usually the standard-sized heater is not enough to fully fill up a walk-in bathtub.
For example, if you have an 80-gallon walk-in tub and only a 60-gallon water heater, you will have to fill your accessible tub with 60 gallons of how water and 20 gallons of cold water. The result, as you might imagine, will be a lukewarm bath that really is not a great way to enjoy a tub.
A new 100-gallon water heater costs quite a bit – it is not unusual to spend more than $2,000 on a high-quality heater. On the right, you have an example of a 100-gallon Westinghouse heater that has good reviews on Amazon and costs less than $1,500. Before deciding to get one, be sure to check out the costs of water heater installation.
How Much You’ll Spend For Water And Electricity?
For a normal walk-in bath, you will need around 50 gallons of hot water, give or take. We can actually calculate how much does it cost to fill walk-in tub per a single bath.
All we need is water and electricity price in your particular city. We’ll make this rough calculation for the city of Minneapolis, Minnesota USA (you can check how much a tub full of water costs in your city using some of Circle Of Blue statistics). Here the price of 1 unit of water (748 gallons) costs $3.20. For a single walk-in bath, we need 50 gallons, which equals to about 0.21$. So, just for water, we pay about 21 cents.
What about electricity for heating up water?
According to an article about heating up water, it costs close to 2 cents to heat up a gallon of water. For a walk-in tub, we need to heat up 50 gallons of water and an estimated cost of heating (electricity) is $1.00.
This makes an estimated total for a single walk-in bath of $1.21. If, for example, you want to enjoy a bath every day, this brings the monthly total to $36.3.
Your Experience
If you have an experience or story to share about a walk-in bathtub, especially concerning water heaters, water capacity and the costs of it all, you’re welcome to share your thoughts in the comments below.
When you’re buying any bathtub, knowing the size of the tub is essential – we need to know how much space is needed in the bathroom in order to install it. Knowing what are the dimension of a walk-in tub (width x length x height) is even more important in order to appropriate movement space for our elderly, calculate how much space we’ll leave in the bathroom for a potential wheelchair and, simply put, because choosing the wrong walk-in tub dimensions can result in thousands of dollars in return fees and re-installations.
Do walk-in bathtubs come in different sizes?
Of course. There are several different dimensions of walk-in tubs to choose from and we’ll list 7 most common (and uncommon) ones. One thing everybody is aware of is that a walk-in tub for senior costs, on average, $5,000 to $7,000 with the installation. Choosing the right size of the walk-in bathtub does spare a whole lot of problems down the line.
A standard walk-in tub is 52” long and 30-32” wide (standard-size tub by American Standard).
Below you’ll see exactly what kind of the walk-in tub dimensions are available. You should check all the sizes, from the small ones to the big double-seat accessible tub dimensions, to see which one fits your bathroom the best. If you haven’t yet measured the space in the bathroom for the walk-in tub placement, now would be the time.
Walk-In Tub Dimensions Vs. Dimensions Of A Standard Tub
Odds are that you have a standard tub or a shower or certain size already installed and you want to upgrade it to a safer walk-in tub. In general, if you look at the dimensions of a standard tub vs. walk-in tub, you’ll find out the following:
Width: the same for standard and walk-in tub.
Length: walk-in bathtubs are shorter.
Height: walk-in tubs for seniors are higher/taller.
A standard bathtub is 60 inches long and about 30-32 inches wide. No one really talks about the height of a standard tub; however, in the case of walk-in bathtubs, height is significant – these special safety tubs can be up to 50 inches tall and can hold up to 100 gallons of water.
A traditional tub is 60” long and 30-32” wide (standard-size tub by American Standard).
In contrast, the standard walk-in bathtub length is 52 inches while the width is the same as with standard tubs – 30-32 inches. The longest walk-in tub can reach up to 60 inches and some bariatric tubs (for seniors over 300 pounds) can be 40 inches wide. The smallest tubs for small bathrooms can be as little as 36.5” x 33.5” according to WalkInTubGuide with a height of fewer than 30 inches.
Tip: Pretty much any walk-in bathtub can be installed in place of a traditional tub because the walk-in models are shorter (60” or less).
As far as walk-in tub dimensions are concerned, we also have to consider three other measurements:
Walk-in tub seat width and height.
Tub door width.
The height of step-in threshold.
1. Dimensions Of Walk-In Tub Seat
The built-in seat should be of appropriate width and height for a comfortable bath.
One of the main features of walk-in tubs is a built-in seat (some tubs come without the built-in seat). This enables elderly people to sit comfortably and enjoy a bath. However, in order for an experience to be truly enjoyable, the seat has to be of appropriate width and height.
The standard size of seat we find in a walk-in bathtub is around 21 inches wide and has a height (distance from the bottom of the tub) of 17 inches.
This seat size accommodates everybody with an exception of very tall or short seniors, or people who weight more than 300 lbs.
For taller or shorter elderly people, the seat height of 17 inches might not be perfect. There is not much wiggle space as far as the seat height is concerned but you’re welcome to contact a tub distribution and talk to them about the walk-in tub seat dimensions. There are changes that you’ll be offered a 2 inch higher or lower (depending if you’re tall or short) seat.
For everybody who is heavier than 300 lbs, chances are the walk-in tub seat will be too narrow. For heavier people, wider bariatric walk-in tubs were designed. Instead of standard 30-32 walk-in tub width, the bariatric models are around 40 inches wide and come with a 30-inch wide bariatric walk-in tub seat. Down below you can check the dimensions of bariatric walk-in bathtubs.
2. Tub Door Width – 3 Options
When choosing the right walk-in bathtub dimensions, another thing to consider is tub door width. Generally, there are three kinds of doors:
Normal standard-sized door (narrow)
Bigger and wider wheelchair accessible door (wide)
Bariatric walk-in tub doors (in between)
The most common one is the narrow door. However, if you have a wheelchair or are a caregiver to someone who uses a wheelchair for their daily activities, the wider wheelchair accessible door is a better option.
There a middle option as well. Some normal tubs and most bariatric walk-in bathtubs have a specific door that is narrow below and grows wider at the top. Generally, these are the easiest to use to access a walk-in bathtub.
3. Height Of Step-In Threshold
Of course, this is one of the most important walk-in tub dimension. The whole point of walk-in tubs is that a person entering it doesn’t need to awkwardly lift their leg over into the tub – instead, you can just step into the tub (hence the name ‘walk-in tubs’). However, to enter the accessible tub, we have to step over the threshold which is significantly lower.
The size of the walk-in step-in threshold can be roughly divided into 3 categories:
Standard height – 3” to 7”
High – above 7”
Low – below 3”
A general rule of thumb is that the lower the threshold is the better, especially for elderly people.
7 Most Common (And Uncommon) Walk-in Tub Sizes
Because there is such a variety of walk-in tubs with different dimensions, we created a list of 7 most common walk-in tub sizes and some that are uncommon such as cube walk-in tubs and two-seat walk-in tubs. The format used to indicate the dimensions will be: width x length x (possibly) height, all the numbers are in inches.
1. Standard-Sized Tub – 30” x 52” x 38”
As we’ve discussed before, the length of 52 inches and width of 30-32 inches is the golden standard when it comes to walk-in tub dimensions. The standard height the standard tub reaches is 38 inches, which gives you about 30 inches of water depth. What this means is that when you seat in the tub, the water fully covers you up to the neck.
This most popular dimension for a walk-in tub has a seat with a roughly 21 inches width – more than enough for most elderly.
Here is how a standard-sized tub looks when installed:
Standard-sized tub with a narrow door and air jets.
2. Deep Soaking Tub (For Taller People) – 30” x 52” x 46”
For tall people (over 6 ft.), the standard-sized tub might just not be deep enough. The width and length dimensions of the deep soaking tub are the same as with a standard one, the height, however, is increased from 38” to 46”.
These 8 additional inches is the difference between water reaching up to the neck instead to up to the chest. If the depth wouldn’t be increased, taller people would have to leave their shoulders and upper parts of their arms out of the water which isn’t as comfortable as being fully immersed in hot water.
3. Bariatric Tub (For People Over 300 lbs) – 40” x 52” x 38”
For people who are heavier than 300 lbs, the standard walk-in tub dimensions might not be optimal. This is why bariatric tubs were designed that are generally the same as the standard tubs albeit being considerably wider with a wider built-in chair.
While a standard width of a walk-in tub is 30”-32”, the bariatric tub is 40” wide. This also enables the installation of a wider 30” seat that is much more comfortable than a standard-sized one. Here is an example of the extra-wide walk-in tub:
The extra-wide 41” tub by Ella Bubbles comes with a 30.5” wide seat.
4. Long Walk-In Tub – 30” x 60” x 38”
Standard tubs are usually 60” long and, in general, walk-in tubs are shorter – 52”. However, if you want a longer accessible bathtub, you’ll easily find one that is 60” long.
These tubs are considered walk-in bathtubs for a large bathroom but given that it is only 6 inches longer, you can install it without much problems in a regular-sized bathroom. Nonetheless, it would be wise to first test such a long walk-in bathtub and check if you feel comfortable sitting in one. What one has to remember is that walk-in tubs are made for seating and don’t have to be as long as regular bathtubs where you can mostly lie down horizontally.
5. Long And Wide Bathtub (For Big Bathrooms) – 36” x 60” x 38”
One of the biggest available dimensions for a walk-in tub is the 36 inches wide and 60 inches long bathtub. Of course, with such a big tub, you’ll have to figure out where to put it. That’s why this is the most viable option for seniors who have big bathrooms.
What is worth remembering is that long and wide walk-in tub is one of the few accessibility tubs that are bigger than an ordinary bathtub. If you have a regular tub already installed and want to upgrade it to this big version of a walk-in bathtub, you’ll have to think about expending the space that is intended for a bathtub in your bathroom. In turn, this will mean you’ll have less free space to move around the bathroom. In a bigger bathroom this usually isn’t a problem, but with the standard-sized or smaller bathroom having a big walk-in bathtub is a less viable option.
6. Rectangular Walk-In Tub (For Small Bathrooms) – 32” x 38” x 36”
If you don’t have enough space in the bathroom, a smaller walk-in tub could your fit nicely in an empty corner. The smallest walk-in tubs are called ‘rectangular’ or ‘cube’ walk-in bathtubs and it’s easy to see why if you look at the photo below:
The smallest walk-in bathtub is cube-shaped, perfect for small bathrooms.
Being only 38” long, the rectangular walk-in tub requires the least amount of bathroom space. What is more, it can perfectly fit into a corner that you just might not be using. The seat is of standard width; however, be sure to test how the small walk-in tub dimensions fit you.
The cube tub is the shortest of all tubs and you might have problems with where to put your feet. Some seniors can experience a similar claustrophobic feeling you might feel on an overbooked plane with little foot space. You can easily take the measurements and plan where in the bathroom to put it but in order to ensure you’ll have a great experience, it is very important to test the rectangular walk-in tub first.
7. Two-Seat Walk-In Tub (For 2 Persons) – 36” x 80” x 38”
What about if two seniors want to take a relaxing bath together? With one of the biggest walk-in tubs – the two-seater – this is no more a problem.
It is not uncommon for a married elderly couple to spend an evening bathtubbing but it does require one of the most uncommon tubs to do it:
The biggest walk-in bathtub for 2 persons is 80” long.
As you can see, the biggest walk-in tub is 20” longer than a standard bathtub, and 4” wider. If you look at different tub sizes, this is one of the biggest tubs of any kind.
When thinking about where to put this model, be aware that it is much bigger than your existing bathtub. You’ll have to find a lot of space to accommodate it but if you want to share your bath with your spouse, we hope you’ll find the space.
Finding A Place In The Bathroom
To sum it all, it is important to measure the bathroom and figure out a walk-in tub of what dimensions you can safely place in your home. Of course, do consider how you’re going to move around the bathroom as well – especially if you’re choosing a bigger walk-in tub.
Don’t forget that you’ll have to pick a place in the bathroom that is well connected as far as piping and, in case you’ve decided for a sophisticated model, electricity is concerned. It is nigh impossible to install a walk-in tub across the room from the piping, regardless of the dimensions.
If you have an experience about how best to pick the dimensions of walk-in bathtubs, you can share it in the comments below.
