150 litres every time you fill the bathtub. Read that again.
One hundred and fifty litres. At minimum. That’s what a standard bathtub swallows — the kind found in 70% of flats in Valencia. The larger ones — those 170 cm models the builders put in during the 80s — easily reach 200 litres.
To put it in perspective: the INE (National Statistics Institute) puts the average water consumption in Spain at 133 litres per person per day. A single bath uses more than everything one person consumes in an entire day. Showering, cooking, doing the laundry, washing up, flushing the toilet. All of it combined doesn’t reach what you use up in a 20-minute bath with bubbles up to your neck.
Now, we’re not here to make anyone feel guilty. The occasional bath is a perfectly legitimate pleasure. But if your daily routine includes filling the bathtub because it’s all you have, the numbers don’t lie. Let’s get into them.
How much water a bathtub uses
It depends on the size, obviously. But the ranges are quite stable because Spanish bathtubs follow a very similar standard:
- Standard bathtub (150-160 cm): 150-180 litres for a normal fill (not to the top, but at a comfortable bathing level).
- Large bathtub (170-180 cm): 180-220 litres.
- Freestanding bathtub: 200-300 litres, depending on the model.
- Half bath (filling only halfway): 75-100 litres.
And mind you, those litres are just water. You need to add the energy to heat half that volume. A gas heater needs 15-20 minutes to heat 100 litres to 38-40 degrees. On the gas bill, each bath costs between €0.80 and €1.20 in energy alone.
On top of that, during the bath the water cools down and many people turn on the tap to add hot water halfway through. Those extra 20-30 litres nobody counts, but there they go.
How much water a shower uses
Here’s where things get interesting, because the shower has a variable the bathtub doesn’t: time. And time is something you control.
A conventional shower head (no flow limiter, no aerator, the old-fashioned kind) delivers 10 to 15 litres per minute. A modern tap with water-saving technology drops to 6-8 litres per minute without any noticeable difference in pressure.
Do the maths:
- Quick shower (5 minutes) with conventional tap: 50-75 litres.
- Quick shower (5 minutes) with thermostatic tap + aerator: 30-40 litres.
- Normal shower (8 minutes) with conventional tap: 80-120 litres.
- Long shower (12-15 minutes): 120-225 litres. Yes, a very long shower can use as much as a bath.
The key point: a 5-minute shower with a good tap uses between 4 and 6 times less than a bath. But if you stay for 15 minutes with the old tap at full flow, the advantage evaporates. Literally.
Comparison table: all scenarios
Let’s put it all together for an at-a-glance view:
| Scenario | Litres per use | Water cost (Valencia) | Energy cost | Total per use |
|---|---|---|---|---|
| Full bathtub (standard) | 150-180 L | €0.45-€0.54 | €0.80-€1.10 | €1.25-€1.64 |
| Large bathtub | 180-220 L | €0.54-€0.66 | €1.00-€1.30 | €1.54-€1.96 |
| Half bathtub | 75-100 L | €0.23-€0.30 | €0.40-€0.55 | €0.63-€0.85 |
| 5-min shower (conventional tap) | 50-75 L | €0.15-€0.23 | €0.25-€0.40 | €0.40-€0.63 |
| 5-min shower (thermostatic tap) | 30-40 L | €0.09-€0.12 | €0.15-€0.20 | €0.24-€0.32 |
| 8-min shower (conventional tap) | 80-120 L | €0.24-€0.36 | €0.40-€0.65 | €0.64-€1.01 |
| 12-min shower (conventional tap) | 120-180 L | €0.36-€0.54 | €0.65-€1.00 | €1.01-€1.54 |
Costs calculated with EMSHI (Metropolitan Entity for Water Services) rates for Valencia in 2026: full water cycle per cubic metre around €2.80-€3.00/m³.
The conclusion is obvious. And the numbers only improve if you use efficient taps.
The money calculation: real annual savings in Valencia
Let’s do the real sums. Let’s suppose a family of 3 in Valencia, each showering once a day.
Scenario A: Daily bathtub (one of the three takes a bath, the other two shower with an old tap)
- 1 daily bath: 170 litres
- 2 showers of 8 minutes with conventional tap: 200 litres
- Daily total: 370 litres
- Annual total: 135,050 litres (135 m³)
- Annual water cost: ~€405
- Annual energy cost: ~€580
- Total: ~€985/year
Scenario B: Showers for everyone with thermostatic taps, 5 minutes
- 3 showers of 5 minutes with thermostatic tap: 105 litres
- Daily total: 105 litres
- Annual total: 38,325 litres (38.3 m³)
- Annual water cost: ~€115
- Annual energy cost: ~€165
- Total: ~€280/year
The difference
- Annual savings: ~€705
- Water savings: 96,725 litres (nearly 97,000 litres)
- Over 5 years: ~€3,525 and nearly half a million litres of water
These aren’t theoretical figures. They’re basic maths with real tariffs from Aguas de Valencia. And we’re not counting the savings on cleaning products or the time lost waiting for the bathtub to fill.
If this has convinced you and you want to know how the changeover process works, we have a complete guide: replacing bathtub with shower without construction.
Taps and accessories that really save water
Not all the savings come from switching bathtub for shower. A good part comes from the taps you put in that shower. Here are the three key elements:
Thermostatic tap
This is the most important change. A thermostatic tap maintains a constant temperature, eliminating those minutes of adjusting hot and cold every time. Models with EcoStop function (Grohe has SmartControl, Roca the T-1000) include a stop at 38 degrees that you have to consciously press to go higher. Less time with the water running, less waste.
Savings compared to a conventional mixer tap: 20-30%.
Aerators and flow limiters
An aerator mixes air with the water before it comes out. The sensation of pressure is the same (or even better), but the actual flow drops from 12-15 L/min to 6-8 L/min. You can buy them for €5-€10 and screw them on yourself. It’s the investment with the best return in any bathroom.
For showerheads, look for those indicating a flow rate of 6-8 L/min. Grohe calls them EcoJoy, Roca uses the Cold Start range.
Low-consumption showerhead
The latest generation of showerheads use internal turbine technology to accelerate the droplets, creating a sensation of power with less water. A good low-consumption showerhead uses 6 litres per minute compared to 12-15 from a conventional one. In our smart-tech designs section you can see the options we regularly install.
Combining a thermostatic tap + aerator + low-consumption showerhead, the accumulated savings are around 40-50% compared to a conventional installation.
The part nobody wants to hear: Valencia has a water problem
In Valencia, with restrictions on the Xúquer river and the drought episodes of 2023-2024, talking about water consumption isn’t an abstract topic. It’s something that directly affects tariffs, irrigation restrictions, and conversations in any bar around the Mercat Central.
The Xúquer basin has been in structural deficit for years. The Tous and Bellús reservoirs recorded historic lows in the summer of 2024, and the Júcar River Basin Authority has raised the alert level several times in the last three years. Climate change isn’t a distant projection for the Valencia region — it’s a reality already impacting the water supply.
Domestic consumption represents approximately 15-17% of total water consumption in the Xúquer basin (the bulk goes to agriculture). But that percentage is no excuse for not acting. Water tariffs in Valencia have risen by 18% in the last 5 years, and the trend is upward. If every household in Valencia reduced their bathing water consumption by 40%, we’re talking about millions of cubic metres per year. And that does make a difference to the reservoirs and the network’s capacity to withstand increasingly dry summers.
8 tricks to reduce bathroom water consumption even further
You already know that switching bathtub for shower is the big step. But there are many small steps that add up:
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Put a visible timer in the shower. It sounds silly, but it works. When you see you’ve been there 5 minutes, you get a move on. They cost less than €10 at any hardware store.
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Turn off the tap while soaping up. If you soap your body and hair with the tap off, you save 2-3 minutes of water per shower. At 8 litres/minute, that’s 16-24 litres each time.
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Collect the cold water while waiting. While the water heats up, put a bucket underneath. Those 5-8 litres of cold water can be used to water plants, mop the floor or manually fill the cistern.
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Check dripping taps. A tap that drips one drop per second wastes 30 litres per day. Per year, almost 11,000 litres. For want of changing a €2 washer.
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Install a dual-flush cistern. The short flush (3 litres) is sufficient for 80% of uses. The savings compared to an old 9-12 litre cistern are enormous.
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Don’t leave the basin tap running while brushing your teeth. Two minutes with the tap open is 16-20 litres. Wet it, close, brush, open, rinse. That’s 2 litres at most.
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Do preventive maintenance on your water heater. A heater with built-up limescale takes longer to heat the water, which means more time with the tap running waiting. Annual maintenance prevents that.
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If you’re renovating, plan the distances. The further the heater is from the tap, the more cold water is wasted. In a full renovation you can optimise the pipe routing.
Frequently asked questions
How much water does a bathtub use compared to a shower?
A standard bathtub uses 150-200 litres per use. A 5-minute shower with a conventional tap uses 50-75 litres, and with a thermostatic tap it drops to 30-40. The difference is at least 3 to 1 and reaches 6 to 1 with efficient taps. More details in our shower or bathtub guide.
How much money do I save per year switching from bathtub to shower in Valencia?
A family of 3 can save between €500 and €700 annually (water + energy) by switching from a daily bath to 5-minute showers with thermostatic taps. Over 5 years, €2,500-€3,500. Calculate your case in our calculator.
Does a long shower use the same as a bath?
Yes, it can happen. A 12-15 minute shower with a conventional tap (12-15 L/min) uses between 140 and 225 litres, equalling or exceeding bath consumption. The key is to keep the shower under 7-8 minutes and use low-flow taps.
Which tap saves the most water in the shower?
The thermostatic tap with EcoStop is the most efficient option. Brands like Grohe (SmartControl) and Roca (T-1000) reduce flow by 30-40% without sacrificing the experience. Combined with a low-consumption showerhead (6 L/min), savings are around 50%.
Is it true that Valencia has water restrictions?
The Valencia region is one of Spain’s areas with the greatest water stress. The Xúquer basin experienced severe drought episodes in 2023-2024, with reservoirs at historic lows. Tariffs have risen 18% in five years and the trend is upward. Reducing domestic consumption isn’t just saving money: it’s responsibility towards the region. If you’re concerned about this, look at the 8 real problems of having a bathtub and why more and more Valencian families are making the switch.
It’s clear to us
We’re quite clear: a 5-minute shower with a thermostatic tap is the smartest option. For your wallet, for the planet, and for Valencia in particular.
You don’t have to give up comfort. Modern showers with an extra-flat tray, glass screen and thermostatic taps are a better experience than the old bathtub you have now. And with savings of nearly 100,000 litres of water per year for an average family.
If you’re thinking of making the switch, visit our calculator to see the numbers for your specific situation. And if you have doubts about whether your bathroom can handle the conversion, take a look at our guide to replacing bathtub with shower without construction.
At Reformarte we’ve been doing exactly this in Valencia and surroundings for years. Every bathtub we remove is a bill that goes down and a bathroom that gains space. If the figures add up for you — and they do, because they’re real data — the next step is ours.
Calculate your bathtub-to-shower swap price
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