Concrete repair, spalling repair and rendering in difficult access situations

So picture yourself 35 stories above the cbd, abseiling the outside of a building. You’ve been told that there’s a leak inside a commercial office space on level 35 and that it’s unknown what is causing this. When you get down to level 36, you notice that there is a spall that has formed in the area between the two levels.

It’s evident that water is getting behind the concrete or render. The spall looks somewhat stable, but you know that over time this piece of concrete is going to fall to the street below. So, it’s your job to fix it.

You take some photos and descend to the ground. You meet up with the building manager and advise him of the spall, which of course, he couldn’t see from the outside. Your project manager/estimator supplies the client with a quote to carry out the concrete repair. The quote is accepted and you are engaged to fix the repair.

The client is disappointed that it’s not just a seal on an expansion joint, or a window junction, but is accepting of the fact that the repair needs to be done. He or she is also counting himself lucky that you’ve found the repair in time before it falls.

So, the next day the team of abseilers arrive onsite and proceed to set up a customised catch netting system for the area where the works are required. The areas below are cordoned off for public safety and the catch net is in place. The concrete repair team can then get to work repairing the concrete.

They carefully remove the spall, making sure that this is done safely and that no concrete falls. The concrete is disposed of and removed from the works zone. The concrete repairers inspect the reinforcement which appears to have caused this particular spall. It has some corrosion and it is fortunately less than 10% loss in mass. The rebar does not need replacement, but it needs to be treated. The team get to work prepping the steel so that it’s as good as new, applying a corrosion inhibiting substance to the steel once it’s prepped to good shiny metal. Then, the team applies an acrylic polymer modified, high build render and begins to build the patch up. This is done in a couple of stages and is left to dry.

Once the repair is dry, the professional industrial rope access concrete repair team descend the facade to the works zone again and apply the skim coat to match the surrounding surfaces. The repair looks great! The team descends the facade and lets the repair dry.

Then it’s time to paint! The painting team come and descend to the works zone and paint to match the surroundings. They take photos for the client and decommission the catch net. The team descends to the ground, but not before they do a thorough visual inspection of the surrounding area and those areas below the repair. They make sure they can’t see any similar problems developing in the area surrounding the repair site. Once it’s been established that there are no other visible repair needs, or any other obvious areas where water can get in, the job is done.

After the final paperwork and report is supplied to the client, the project manager checks in with the client a few weeks later after the first rain comes through. The client is happy, as the leak has stopped and the tenants of the building are now happy as their internal office areas are leak free!

Another successful story from the industrial rope access team.