SWConsult were engaged to provide an interim solution on water ingress from a residential pool surround (level 4) into the commercial property below on a city high rise. We provided the contractor with a Scope of Works for deconstruction and localised repairs. During the works, Autoclaved Aerated Concrete Aeroblock was discovered and found to be structurally defective. We do not endorse Autoclaved Aerated Concrete as a suitable substrate to waterproof over due to its high porosity despite what the membrane and “Aeroblock” manufacturers may state. An analogy can be drawn between the QBCC rejection of particle or chip board on bathrooms due to its lack of durability in external wet area locations.

Parapet and balustrade constructed with Autoclaved Aerated Concrete (ACC) panel. AAC in poor condition and affected by moisture.

Autoclaved Aerated Concrete (AAC) wall panel with areas crumbling due to moisture.

Base of wall deconstructed

Narrow reinforcement bar found in panel during investigative deconstruction. Deconstruction revealed metal angle installed under the wall panel with severely corroded vertical flange.

Close up view of corroded base angle.