Field & trade terms
Spalling
Also called: spall, spalled concrete
Spalling is when pieces of concrete or masonry break, flake or pop off the surface, leaving craters or exposed aggregate and sometimes exposed reinforcing steel. It has a few common drivers: rebar that sits too close to the surface corrodes and forces the cover off, water trapped in the material freezes and expands, or a weak, over-wet or poorly consolidated placement never had the durability to begin with. Wherever it comes from, spalling is deterioration of the structural surface, not just a finish blemish.
Why it matters
Spalling around exposed rebar is a feedback loop: once the steel is exposed it corrodes faster, which drives off more concrete, which exposes more steel. Left alone it works its way into the section, so spalling that reaches the reinforcement is a repair to schedule, not a cosmetic note to defer.
It also points back at a root cause worth finding — thin cover, a bad mix, a freeze-thaw exposure the concrete was not specified for. Patching the crater without addressing the cause means the same failure returns nearby.
How it shows up on site
Flaking or broken concrete faces documented at inspection, traced to a cause — cover, mix, exposure — and where reinforcement is exposed, written up as a defect with a repair disposition rather than left to progress.
Standards it's verified against
Checklists that put spalling to work
Free, field-ready checklists, each with the photo every item needs before it can be submitted.
Related terms
- Concrete coverThe thickness of concrete between the reinforcing steel and the surface — the protective layer that keeps rebar from corroding and fire from reaching it.
- EfflorescenceThe white, powdery salt deposit that appears on masonry or concrete when water moving through the material carries dissolved salts to the surface.
- DelaminationA separation between layers that were supposed to bond — a coating from its substrate, a topping from a slab, plies of a membrane — leaving a hollow, loose plane.
- DefectA flaw in materials or workmanship that makes the work fall short of what was specified or of accepted trade practice.
- MEP (mechanical, electrical, plumbing)The mechanical, electrical and plumbing trades — the systems run through a building's structure that get inspected at rough-in and again at final.
- FirestoppingSealing openings where pipe, conduit or cable pass through a fire-rated wall or floor so the assembly's rating is restored.
Knowing the term is step one. Proving it is the job.
RTI holds the submit button until every mandatory item is answered and the photos are attached, then chains the record so it can be proven untouched later.