This week's word is concrete restoration; the repair of deteriorated concrete and rusted reinforced steel to return the structure back to its original specifications and condition.
The areas that are most severely damaged in condominiums and require the most restoration are typically balconies and elevated decks, e.g. parking garages.
The damage is caused by moisture intrusion that results in rebar (reinforced steel) rusting. When the rebar rusts, it expands and causes cracks and spalling (pitted, flaking or broken areas of concrete).
One of the most challenging parts of a concrete restoration project is estimating the cost. Why? Because the damage is below the surface. Without removing the concrete, you cannot be certain of the damage that needs to be repaired. Hiring a highly qualified engineer is critical in the project. The engineer will complete a site survey and estimate the amount of work required, but it will only be an estimate.
Here is a great article that includes a more complete description: The ABCs of a Concrete Restoration Project.