Waterproofing and concrete repairs come before painting for one unforgiving reason: paint will not fix underlying building issues, it will only hide them, briefly and expensively. A coating applied over spalling concrete, failed membranes or active moisture paths fails from behind, usually within a couple of years, taking the repaint budget with it and leaving the defect worse for the delay. The correct sequence on any building showing its age is investigate, repair, waterproof, then paint, and the projects that follow it get a decade from the coating, while the projects that skip to the painting get a lesson.
For building managers and committees, this is the single most valuable thing to understand before tendering a repaint, because it is exactly where the cheapest quote and the best outcome part company.
What is concrete spalling, and how is it fixed?
Spalling, commonly called concrete cancer, is what happens when the steel reinforcement inside concrete corrodes. Carbonation of the concrete over decades, and chloride attack in coastal air, strip the steel of its protection; the rust that forms expands to several times the steel's volume; and the expansion cracks and forces off the concrete covering it. The symptoms climb a ladder: rust staining, hairline cracks tracking the reinforcement lines, drummy concrete, then chunks letting go from balconies and soffits, which is the point where a maintenance item has become a safety one.
The repair is a designed process, not a patch: the defective concrete is broken out past the corrosion, the steel is cleaned and treated with corrosion protection, the section is reinstated with specified repair mortars, and the surface is finished ready for protective coating. Done properly, the repair outlasts the concrete around it. Done cosmetically, with filler and paint over the stain, it returns within a couple of seasons wearing the new paint as camouflage, which is why cheap repaints on ageing concrete buildings are the most expensive kind.
Why membranes and moisture come first
Water is behind almost every coating failure worth the name. Failed waterproofing membranes on roofs, planter boxes and balconies, perished sealant joints, and cracked capping all feed moisture into the structure, and moisture inside a wall does two things to a new repaint: it lifts the coating from behind as it tries to escape, and it keeps the corrosion chemistry running underneath the fresh colour. So the moisture path gets fixed at its source first, membranes renewed, joints resealed, falls corrected, and the substrate gets its drying time before coating systems go on. On buildings with a moisture history, the coating itself is then specified accordingly, with membrane-grade and elastomeric systems where the manufacturer's specification calls for them. Sequence, then specification: that is the whole discipline.
What this means for your scope of works
Here is where it lands for the person running the tender. A repaint scope that ignores the building's defects is not a cheaper project, it is an unpriced one: every spall and failed joint discovered after award returns as a variation, at height, at variation rates, and the wrong scope, or a scope that misses things, is precisely how repaint budgets blow out. The fix is procedural and cheap: a condition inspection before the scope, remedial works itemised inside the scope, and quotes gathered against the whole document, so the numbers you compare all describe the same building.
The structural question to ask every tenderer follows directly: who does the remedial work? Painting companies that cannot deliver it hand you a second contractor and an interface where the two trades meet, which is exactly where warranties go to argue. We deliver concrete repair, waterproofing and the rest of the remedial building work and the body corporate repaint that follows it under one contract with a single project manager, our own employed trades on both sides of the sequence, so the repair standard and the coating system are designed together and warranted together. On an ageing building, that one-contract structure is not a convenience; it is the quality system.
Frequently asked questions
Should you waterproof before painting?
Yes, wherever moisture has a path: membranes, sealants and falls are repaired first, the substrate dries, then the coating goes on. Painting over active moisture fails from behind.
What is concrete spalling and how is it fixed?
Corroding reinforcement expanding and breaking the concrete around it. Repair means breaking out to sound material, treating the steel, reinstating with specified mortars, then protective coating.
What is remedial building work?
The structural and envelope repairs, concrete repair, render restoration, waterproofing, sealant replacement, that restore a building's integrity, sequenced before presentation work like painting.
Why should remedial work and painting be under one contract?
Because the interface between repairer and painter is where responsibility and warranties fall apart. One contract, one project manager and one warranty keep the sequence, the standards and the accountability whole.
Managing a building where the paint is hiding more than fading? Book a condition inspection or call 1800 313 083, and get the repairs and the repaint scoped as one project.