How does the shower pump calculator decide if I need a booster pump?

It compares the pressure your shower needs against what your supply actually delivers. For an overhead tank it takes gravity pressure as height above the shower times about 0.0981 bar per metre (1 bar is roughly 10.2 metres of water head), then derates for pipe size and how many outlets run together. If that available pressure falls below what your shower type needs, it flags a pump and suggests a size.

What inputs do I need and what are sensible defaults?

You need the tank height above the shower head (or a direct supply pressure in bar), your shower type, feed pipe size and how many outlets run at once. Typical Indian homes use a 15 or 20 mm CPVC feed and a tank a metre or two above the roof slab. A hand shower wants about 0.5 bar, a standard overhead about 0.8 bar, and a rain head roughly 1.7 bar, so rain heads on low tanks are the common pump case.

How accurate is the result and what should I verify?

Treat it as an indicative planning guide, not a guaranteed spec. It uses a static-head model and typical derates, but real pressure shifts with tank fill level, long pipe runs, bends, valves and fittings. Before buying, get a plumber to take a gauge reading at the outlet, size an automatic pressure-boosting pump to your flow and outlets, and confirm sizing and any wiring against manufacturer data and local norms.

Shower Pump Calculator

Do you need a shower pump?

Enter your overhead tank height, shower type and how many outlets run together. Get the available pressure versus what your shower needs, a clear verdict, and — if short — the booster pump HP and indicative ₹. Indicative India 2026; confirm with your plumber.

Your supply & shower

Tank height above shower (ft)

Shower type

Outlets running together

Feed pipe size

Gravity pressure ≈ tank height × 0.0981 bar/m (1 bar ≈ 10.2 m of head). Smaller pipe and more simultaneous outlets lower the pressure that actually reaches the shower. Numbers are indicative — a plumber's on-site gauge reading is the real check.

Verdict

Needs a 1.5 HP booster pump

Available 0.00 bar vs 1.7 bar required — short by 1.48 bar (~₹15,000–₹28,000 pump).

Available pressure

0.22 bar

2.4 m head, 1 outlet(s)

Required pressure

1.7 bar

for a comfy flow

Recommended pump

1.5 HP

boosts ~1.68 bar

Indicative pump ₹

₹21,500

₹15,000–₹28,000 range

Available vs required pressure, and the level a booster pump would restore. Indicative — confirm with your plumber.

Plan the pump & plumbing

Get pump type, placement and pipe advice for this bathroom from DesignAI.

Go deeper

Shower water flow calculator Geyser size calculator Bathroom cost calculator

Estimates are indicative and use a static-head model (1 bar ≈ 10.2 m of water) with typical pipe and multi-outlet derates. Real pressure depends on tank fill level, pipe runs, bends, valves and fittings. Always confirm with a plumber's gauge reading on site, and choose an automatic pressure-booster pump matched to your outlets and rating — indicative ₹ exclude installation.

Frequently asked questions

How does the shower pump calculator decide if I need a booster pump?: It compares the pressure your shower needs against what your supply actually delivers. For an overhead tank it takes gravity pressure as height above the shower times about 0.0981 bar per metre (1 bar is roughly 10.2 metres of water head), then derates for pipe size and how many outlets run together. If that available pressure falls below what your shower type needs, it flags a pump and suggests a size.
What inputs do I need and what are sensible defaults?: You need the tank height above the shower head (or a direct supply pressure in bar), your shower type, feed pipe size and how many outlets run at once. Typical Indian homes use a 15 or 20 mm CPVC feed and a tank a metre or two above the roof slab. A hand shower wants about 0.5 bar, a standard overhead about 0.8 bar, and a rain head roughly 1.7 bar, so rain heads on low tanks are the common pump case.
How accurate is the result and what should I verify?: Treat it as an indicative planning guide, not a guaranteed spec. It uses a static-head model and typical derates, but real pressure shifts with tank fill level, long pipe runs, bends, valves and fittings. Before buying, get a plumber to take a gauge reading at the outlet, size an automatic pressure-boosting pump to your flow and outlets, and confirm sizing and any wiring against manufacturer data and local norms.

Related Guides — Deep-dive reading

Bathroom Water Supply India: Cold & Hot Feed, Pipe Sizing, Pressure & Booster Pumps (2026)

How water actually reaches your fixtures in an Indian home — gravity-fed cold from the overhead tank, hot from the geyser, the pipe sizes that decide whether your shower gushes or dribbles, isolation valves at every fixture, booster pumps and hard-water protection, all mapped to IS 1172.

Bathrooms

Gravity-Fed Plumbing System in India: How Overhead Tanks Push Water to Every Tap

The overhead-tank-to-fixture model that most Indian homes run on — how head height creates pressure, why the tank sits on the roof, how much pressure each floor really gets, how to size pipes for gravity flow, and exactly where gravity struggles and how to fix it.

Plumbing

Low-Rise Plumbing Systems in India: Houses, Villas & Buildings up to 4 Storeys

How plumbing is organised for independent houses, villas and low-rise buildings up to about four storeys — the simple overhead-tank gravity model, when a small booster is still worth adding, single- versus multi-floor distribution, and the simpler stack and venting a low building can get away with.

Plumbing

Related Tools — You may also find these useful

Shower Water Flow Calculator

Shower water use per shower, day and month by head type, plus a pressure-adequacy check for your tank height or pump and low-flow savings.

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Estimate the all-in cost of building or renovating a bathroom — by size, quality tier and city, with a category-wise breakdown.

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Check a bathroom against barrier-free clearances (wheelchair turning, WC transfer, door width) with a 0-100 accessibility score.

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