Home / Capacity guide
Educational Not a remote diagnosisWhat size storage water heater do I need?
Starting points for Singapore homes — not a substitute for measuring ceiling space, demand and pipework, and not a remote diagnosis. Typical HDB horizontal tanks are around 15–25 litres.
Educational only. Final size depends on simultaneous use, shower type (rain vs hand), recovery expectations and physical space. We confirm after photos or survey.
Starting point by household
| Situation | Typical starting range | Notes |
|---|---|---|
| HDB · 1 bathroom · 1–3 people | ~15–20 L | Often enough for one shower at a time; instant may also fit |
| HDB · 2 bathrooms · staggered use | ~20–25 L | Or one heater per bathroom |
| Condo / HDB · rain shower · dual use | ~25 L+ | Survey ceiling space and support |
| Landed · multi-bath · family | Larger / multi-tank | Demand + recovery drive size; heat pump may enter the conversation |
| Commercial / multi-user | Assessment required | Do not size from this table |
What changes the answer
- Two showers at once vs staggered use
- Rain shower vs standard hand shower
- Kitchen point on the same tank
- False ceiling depth and access
- Incoming pipe size and pressure
Instant vs upsizing storage
If you only ever run one point, a well-matched instant unit may be simpler than hanging a tank. If you regularly run out or want steadier pressure, storage (or dual instant) is usually the conversation — see the comparison guide.