Can I repair spalling concrete myself?
HDB says owners can repair small areas themselves: remove the spalled concrete, wire-brush the exposed bars, apply two coats of anti-rust paint, apply a bonding agent, patch with polymer-modified cement mortar and repaint. For larger areas HDB advises engaging a contractor promptly. Anything beyond a small patch, or any spalling on structural members other than a ceiling slab, should be assessed by a professional before repair.
From the RRD Field Guide, checked against the sources cited in Concrete Spalling in Singapore: Causes, Risks, Repair Methods and Who Must Fix It. General information, not advice for your project.
The fuller picture
Spalling concrete is concrete cover cracking and breaking away because the steel reinforcement inside has corroded, usually after carbonation or chlorides destroy the steel's natural protection. Small patches can be repaired by removing loose concrete, cleaning and priming the steel and patching with polymer-modified mortar. Extensive spalling, beams, columns or cantilevers need a Professional Engineer. Owners repair inside HDB flats; MCSTs repair common property.
More questions on this topic
- What is spalling concrete?
- Is spalling concrete dangerous?
- Who pays to repair spalling concrete in an HDB flat?
- Who pays to repair spalling concrete in a condominium?
- Does spalling repair need BCA approval?
- Why does spalling come back after repair?
- How is spalling linked to the Periodic Structural Inspection?