Case 2
- Introduction
- Causes of Defects
- Good Practices
- Standards
- Maintenance and Diagnostics
- Remedial
- Similar Cases
- References
Introduction
Type of Building: Public
Blisters are formed in the paint coating of wet area slab soffit. Blistering is almost always caused by moisture, either water vapour or actual moisture drawn through the substrate to the paint interface, in these locations [1-4]. Some other possible factors could be:
- Poor surface preparation
- Failing to remove chalk residue
- The application of hard primer, glossy or contaminated or the latex paint below the minimum recommended temperature
- Application of paint on warm surfaces
Bubbles hence resulted from the localized loss of adhesion and lifting of the paint film from the underlying surface.
Moisture seepage can be best retarded by the dense concrete and good waterproofing membrane [5]. However, via capillary action, water will travel through the concrete if it is porous and to the paint film when the waterproofing membrane is not effective. The functional performance of these systems depends on many factors such as material performance, quality of workmanship at site etc [6-8].