Which Water Storage Tank Is Right for Me?
A Practical UK Guide for Property Owners, Contractors & Specifiers
How to choose a water storage tank?
Choosing the right water storage tank isn’t just about capacity or price. It’s about compliance, longevity, installation constraints, and long-term risk.
This guide walks you step-by-step through the key decisions so you can choose the right tank for your project – first time.
Step 1. What Will the Water Be Used For?
This is the most important starting point, as it directly affects compliance and material choice.
Potable (Drinking) Water
Used for:
- Domestic supply
- Food & beverage facilities
What you must check
- Compliance documentation for inspectors
Not all tanks marketed as “water storage” are suitable for potable use.
Non-Potable Water
Used for:
- Process water
- Greywater systems
What matters most
- Structural integrity
- Durability
- Correct labelling and segregation
If unsure: Always assume potable requirements — it’s safer and future-proofs the installation.
Step 2. How Much Water Do You Need to Store?
Tank sizing errors are one of the most common (and expensive) mistakes.
Consider:
- Daily water demand
- Peak usage periods
- Fire protection requirements
- Backup capacity during outages
Common mistakes
Undersizing (leads to pressure issues or supply failure)
Oversizing (wasted cost and space)
Best practice: Size for real demand + regulatory or safety margins, not guesswork.
Step 3. Where Will the Tank Be Installed?
Installation environment often dictates the tank type more than capacity.
Internal Plant Rooms
Key considerations:
- Door widths and ceiling height
- Assembly space
- Ongoing maintenance access
Best solution: Modular or sectional tanks that can be assembled on site.
External Installations
Key considerations:
- Weather exposure
- Structural support
- Ground conditions
- UV and temperature resistance
Best solution: Tanks designed for environmental durability and long service life.
Step 4. What Material Is Right for Your Application?
Different materials behave very differently over time.
|
MATERIAL
|
STRENGTHS
|
LIMITATIONS
|
|---|---|---|
|
Steel
|
High Strength
|
Corrosion Risk, Coatings Degrade
|
|
Basic GRP
|
Lightweight
|
Variable Quality, Deformation Risk
|
|
Advanced SMC
|
High Durability, Hygienic, Stable
|
Higher Upfront Cost, Lower Lifetime Cost
|
Best practice: Choose material based on lifespan, hygiene, and compliance – not just cost.
Step 5. What Level of Compliance & Risk Do You Have?
Some projects carry much higher inspection and liability risk.
Higher-risk environments include:
- Public buildings
In these cases, documentation, traceability, and certification matter as much as the tank itself.
Ask yourself
- Will this pass inspection first time?
- Can I easily prove compliance years later?
- Is full documentation available?
Step 6. Who Will Install and Maintain the Tank?
A technically excellent tank can still fail if:
- Installation guidance is unclear
- Access for cleaning wasn’t considered
- Spare parts or support aren’t available
Safer choice:
- Clear installation manuals
- Ongoing technical support
- Easily replaceable components
- Proven use across similar projects
Quick Decision Guide
You likely need a high-quality sectional tank if:
✔ It’s potable water
✔ It’s installed indoors
✔ Compliance risk is high
✔ Long service life matters
You may have more flexibility if:
✔ It’s non potable
✔ External installation
✔ Lower inspection risk
Still Not Sure? That’s Normal.
Most projects don’t fit neatly into one category.
The safest approach is to consider:
- Use case
- Capacity
- Installation environment
- Compliance risk
- Long-term cost
Speak to our team directly and they can provide you with more in-depth advice on how to choose a water storage tank tailored to your project needs:
Read More...
- Water Tank Installation & Maintenance
- Cold Water Storage Tanks
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