TPW Wilson Carpark
Structural Steel Sandblasting, Newmarket

TPW

LOCATION

Newmarket, Auckland

SERVICE

Commercial Sandblasting to Structural Steel and Concrete

The Challenge

A fire in the carpark had left steel members and galvanised cable trays coated in soot, with heat affecting the structure and its existing protective coatings. Before any fire protection or topcoats could go back on, the steel needed to be stripped back to a sound, clean condition, with the soot removed from surrounding areas without damaging the substrate beneath it.

Our Approach

BlastOff sandblasted every steel member in the carpark along with all of the high-bond galvanised cable trays, taking the surfaces back to a clean, sound condition suited to recoating. Soot-affected areas were treated separately using soda blasting, a gentler method chosen to lift the soot without damaging the substrate underneath. Preparing the steel and galvanised trays to this standard created a suitable base for the intumescent fire protection and protective topcoats that followed as part of the wider restoration.

The Outcome

Every steel member and galvanised cable tray in the carpark was brought back to a clean, correctly prepared condition, with soot removed from the affected areas without harming the substrate. This gave the subsequent fire protection and coating stages a sound surface to work from, forming the preparation foundation for the carpark’s return to full operation.

Separating Steel From Soot: Fire Recovery Preparation at Wilson Carpark, Newmarket

Fire had swept through the TPW Wilson Carpark in Newmarket, and by the time BlastOff arrived every steel member and every high-bond galvanised cable tray in the structure was carrying soot, heat damage and coatings that could no longer be trusted. Before any fire protection or topcoat could be reapplied, the steel needed stripping back to a clean, sound condition, and the soot needed lifting from surrounding surfaces without damaging the substrate underneath. Those are two different problems, and BlastOff treated them that way.

Every steel member and cable tray was sandblasted back to a condition suited to recoating, while soot-affected areas nearby were soda blasted instead, a gentler method chosen specifically because it lifts soot without chewing into the material beneath it. That distinction mattered across a structure this size, where using one method everywhere would have either left contamination behind or damaged surfaces that only needed a light touch.

The result was every steel member and galvanised tray brought back to a clean, correctly prepared condition, giving the intumescent fire protection and protective topcoats that followed a sound base to bond to, and setting up the carpark’s return to full operation.

Fire and soot damage on structural carparks is rarely uniform, and that is the lesson worth carrying into similar projects. Owners assessing comparable damage should expect a scope that separates structural steel from soot-only surfaces rather than blasting everything the same way, and should ask how the contractor verifies the prepared substrate before fire protection and coatings go back on. For this project, that groundwork sat within a wider job also involving protective coatings, with the sandblasting itself handled through BlastOff’s structural steel and concrete sandblasting service, keeping preparation and finish under one accountable scope.