What do St. Paul’s Cathedral, the Acropolis, Mies van der Rohe’s Farnsworth House, and a badly-maintained parking garage have in common?
They’ve all been damaged by rust jacking.
Rust jacking, also known as “oxide jacking” or “rust burst”, is a phenomenon caused by the oxidation of metal. When a metal that’s prone to oxidizing is put inside another medium, the oxidation exerts tremendous force on whatever the medium around it is.
For example, in England, brass church bells often had an iron staple inserted that held the clapper. Over time as the staple rusted, some bells would completely split in half due to the force exerted by the expanding iron. The Acropolis is another example—an attempted restoration used iron staples, which began to tear the building apart as they expanded from rust.
And modern buildings are just the same. If water gets into structural steel, it can warp and tear the concrete, glass and metal that make up modern buildings. It can crack and buckle concrete, making once-safe floors or walls into structural weaknesses. It’s a severe problem.
But there are ways to combat it.
How to spot rust jacking
If you’re in danger of corrosion problems, there are signs of rust that you can see early if you want to nip that oxidation process in the bud. Rust staining is one of the easiest to see. As water moves through a compromised substrate, it will pick up the rust and stain the outside surface (usually concrete). That’s an immediate call to a contractor.
If you haven’t caught the rust jacking in time, the next sign will be spalling—surface delamination. There will be little thin chips popping off your concrete. As it progresses, the material will split and you’ll be able to see the rusted rebar underneath.
If you’re dealing with a rust jacking problem, you’ll need to remove the parts of your building that are affected and replace them. That’s an involved, expensive process. It’s far better to keep it from happening in the first place. Keep your building weatherproofed and keep the water out so rust jacking doesn’t happen in the first place.
Whether you’re trying to keep water out in the first place or fix problems that have already occurred, it’s a good idea to call a weatherproofing contractor like JK Industries to make sure your building stays in top shape. We’ll get you taken care of.