How to Choose the Right Water Tank Size for a Landed House

Why tank size matters

A storage water tank acts as a buffer whenever the mains supply is cut or pressure drops. In Malaysia, supply disruptions happen more often than we expect — pipe maintenance, major leaks, or a dry season can stop the supply for anything from a few hours to several days.

Choose a tank that is too small and you run dry in the middle of an outage while your family has to ration. Too large and you overpay and waste valuable space around the house. This guide helps you pick the right size for your landed house without waste.

The basic sizing formula

The rule of thumb installers use: allow roughly 250 litres per person per day for all uses — bathing, cooking, laundry and toilets. A four-person household needs roughly 1000 litres of storage to last a full day without incoming supply.

The King Kong stainless steel 1000L tank (from RM2,914) is the most popular choice for a typical terrace house because it strikes the best balance between capacity and footprint.

• 2-3 occupants: 800-1000 litres
• 4-5 occupants: 1000 litres
• 6 or more: 1500-2000 litres

Other factors that affect size

How often supply is cut in your area

If your area suffers frequent disruptions, add buffer capacity. Homes on hills or at the end of a pipe run often need a larger tank because pressure is unreliable and supply is slow to recover. Ask a long-time neighbour how often the water goes off before you decide.

See our install guide for Shah Alam if you live in a densely built area.

Installation space

A vertical stainless steel tank saves floor area compared with a horizontal tank. Before buying, measure the available space — whether on the roof, at the side of the house, or in the back yard — and make sure there is room for maintenance and for the inlet and outlet pipe connections.

Number of bathrooms and usage habits

A home with three bathrooms, a washing machine and a garden to water uses more. If your family enjoys long showers or washes the car often, consider stepping up to a larger size.

Why King Kong stainless steel

A SIRIM-certified stainless steel tank resists algae, withstands Malaysia's heat, and does not leach chemicals into your water the way some cheap plastic tanks can. Its smooth inner surface also makes cleaning easier and keeps the water clear for longer.

It is a long-term investment for the family — buy once, use for well over a decade.

• Lasts 15+ years
• Rust-free and easy to clean
• SIRIM certified for water safety

Overhead vs underground tanks

An overhead (roof) tank uses gravity to give basic pressure to your pipes, but space is limited and the full weight must be supported by the structure. An underground or ground-level tank can be larger and easier to maintain, but almost always needs a pump to lift water to the upper floor. For most double-storey homes, a large ground tank combined with a booster pump gives the best result.

Planning for future needs

If you plan to add a bathroom, a small pool, or the number of occupants will grow (for example parents moving in), choose a tank a size larger than your current need. Upgrading later means paying for installation twice.

Common sizing mistakes

The most common mistake is choosing a tank that is too small to save money upfront, then having to replace it within a year or two. The second mistake is ignoring the position and structural support, which can create a safety problem when the tank is full.

Water quality and your tank choice

Size is not the only consideration — the tank material affects the quality of the water stored. Water that sits for a long time in a cheap plastic tank under heat can absorb odours, while a stainless steel tank keeps the water fresher. If your family stores water for long periods during outages, the material matters more than just the litres.

Getting professional advice

Every home is different — the pipe layout, the area's supply pressure, and usage habits all vary. Rather than guessing, talking to a supplier who can assess your real needs saves money and avoids buying the wrong size. The right advice upfront ensures your system is correct from day one.

A quick buyer's checklist

Before making your final decision, run through the following so you choose the right tank from the start. First, count the number of occupants and multiply by 250 litres to estimate daily needs. Second, think about how often the water is cut in your area and add buffer capacity if needed. Third, measure the available installation space and make sure the base is flat and solid.

Fourth, decide whether you need a pump to lift pressure to the upper floor. Fifth, choose the tank material — stainless steel for durability and long-term water quality. Finally, confirm the tank is SIRIM certified and ask about the warranty and installation. By following this checklist, you avoid common mistakes and ensure your investment meets the family's needs for years. If you are unsure at any step, our team is ready to guide you through each consideration and recommend the option that fits your home best.

Frequently Asked Questions

Is a 1000L tank enough for a family of five?

Yes, for normal daily use 1000L is enough for 4-5 people. If your area often loses supply for more than a day, consider 1500L.

Do I need a pump with the tank?

For a double-storey home, yes — a booster pump ensures enough pressure to the upper floor and showers.

Can the tank be installed on the roof?

Yes, but make sure the roof structure supports the weight of a full tank. Our team will assess the best location.

Conclusion

For most landed homes in Malaysia, a 1000L tank is plenty. Browse our tanks, pumps and combo packages on the products page and book a professional installation.