As silos age, growers face a crucial decision: repair, retrofit, or replace. The first step is always safety. Grain Storage Specialist Chris Warrick advises that growers begin by checking whether the silo is structurally sound. Cracked or tilted bases, rust on critical joints, or weakened bolts and sheets can all compromise safety and increase the risk of collapse. Faulty hatches, ladders, and access points also need to be addressed to protect workers.
If the structure is safe, the next question is whether the silo can still be used for fumigation. To do this legally and effectively, it must pass the AS2628 five-minute half-life pressure test. Warrick notes that retrofitting an old silo to make it sealable is only worthwhile if the structure can actually meet this standard.
Even if a silo cannot be sealed, it can still add value to a grain storage system. Older silos can be put to work with a strong focus on pest prevention. Warrick recommends fitting aeration cooling systems—ideally with automatic controllers—to keep grain temperatures low and insect activity suppressed. Good hygiene is essential, starting with a thorough clean-out, using diatomaceous earth (DE) where appropriate, and applying protectants during loading.
Safe and Sound
Before using or upgrading an ageing silo, growers should confirm that the foundation is stable with no cracks or tilting, that rust or corrosion has not weakened sheets and bolts, and that ladders, hatches, and safety rails are secure. A silo that passes these safety checks may still be fit for service. If not, replacement is the safest option.
Sealed Silo Maintenance
For growers with sealed silos, regular maintenance is non-negotiable. Chris Warrick reminds growers that “a seal is only as good as its last test.” Gaskets, lids, hatches, aeration inlets, and pressure relief valves all require routine inspection. Even small leaks can make fumigation ineffective and increase the risk of chemical resistance.
Pressure testing should be carried out at least once a year and before every fumigation. Many failures are due to inexpensive issues such as worn seals or loose fittings—repairs that are simple but crucial. Warrick stresses that maintaining a seal is far more cost-effective than letting it fail and losing the ability to fumigate properly.
What This Means for Growers
The priorities are clear: safety first, sealability second, and pest management always. If silos are structurally sound, investing in maintenance, aeration, and hygiene can extend their useful life. For sealed silos, pressure testing and gasket checks are the difference between effective fumigation and wasted effort.
With the right approach, ageing silos can continue to serve growers well, protecting both grain quality and worker safety.
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