17/12/2025
5 Signs You Need to Replace Your Oil Tank Before It Starts Leaking
Oil tanks might be an essential part of your home or business heating system, but they don’t last forever. Ignoring the warning signs of a failing tank can lead to costly leaks, environmental damage, and disruption of your heating.
If you’re in Norfolk, Suffolk, Cambridge, Essex or anywhere in East Anglia, knowing what to look for could save you thousands in clean-up costs and prevent stress during the cold months. Here are the 5 key signs that it’s time to consider an oil tank replacement.
1. Visible Corrosion or Rust
Metal tanks naturally degrade over time, especially in damp areas.
What to look for:
- Rust spots, flaking metal, or pitting on the tank surface
- Discolouration around joints or seams
- Even minor corrosion can eventually cause a leak. If you notice rust, schedule a professional inspection immediately.
2. Plastic Tanks Swelling or Bulging
Modern tanks often use high-grade plastics, so while they do not corrode like their metal counterparts, prolonged exposure to UV rays or harsh weather can cause distortion.
Signs of UV damage include:
- Bulging sides or top
- Warped lid or fittings
- Cracks starting at seams
A swollen tank is at very risk of splitting under pressure, so replacement is usually the safest and most effective option.
3. Sudden Increase in Oil Consumption
If your fuel usage suddenly increases without a corresponding rise in heating demand, your tank may be leaking or not holding oil properly. In this case, you should check for oil stains around the tank base and monitor pipework for drips.
Even a small, unnoticed leak can waste hundreds of pounds worth of oil and potentially cause groundwater contamination, which is particularly concerning in rural East Anglia properties.
4. Your Tank is Near or Over 10–20 Years Old
It is worth knowing how long the lifespans of oil tanks are. Older tanks are prone to corrosion, cracking, and component failure. If your tank is reaching the end of its expected life, replacement before a leak is a wise investment. Steel tanks have a usual life span of around 20–25 years, whereas plastic tanks often last 15–20 years. Although this is an average lifespan, tanks can have a much shorter life. If you spot any signs that your tank is deteriorating, act now and don’t wait.
5. Damage or Physical Impact
Tanks can get accidentally damaged by machinery, vehicles, or even falling branches.
Signs of damage include:
- Dents, punctures, or scratches
- Misaligned fittings or valves
- Cracked or weakened bunds on double-skinned tanks
Even a small amount of damage can compromise the tank’s integrity and lead to leaks.
What to Do If You Notice These Signs
- Call an OFTEC-registered engineer to inspect your tank.
- Stop using the tank if a leak is suspected.
- Consider a replacement with a bunded or fire-protected tank for extra safety.
- Transfer remaining oil into a temporary holding container handled by professionals.
- Arrange safe disposal of the old tank.
Don’t wait until it’s too late. Contact Oil Tank Change today to book a free survey and expert advice on replacing your oil tank.
