Concrete crack repairs Melbourne

Not every crack means the same thing, and the repair method depends entirely on which of these you are dealing with:

• Shrinkage cracking Fine, shallow, often map-like cracks that appear as concrete cures. Usually cosmetic, but they let water in.
• Settlement and ground movement Melbourne’s reactive clay soils swell and shrink through wet and dry seasons, which moves slabs and footings. These cracks typically widen over time and are often diagonal.
• Concrete cancer (spalling) Water reaches the steel reinforcement, the steel rusts, and rust expands. That expansion pushes the concrete off from the inside, so you see cracking, bubbling, then chunks falling away with rusted bar exposed underneath.
• Overloading or inadequate reinforcement Cracks that track along the line of the reinforcing steel or appear at points of stress.
• Thermal movement Expansion and contraction where no control joint was provided.

Concrete cancer is the one worth acting on early. Once reinforcement starts corroding, the process accelerates: the expanding rust opens more cracks, more cracks let in more water, and more water corrodes more steel. On balconies, carparks and older apartment blocks it can move from a hairline crack to a structural repair bill in a few seasons.

Signs to look for are rust staining on the concrete face, hollow or drummy sounding areas when tapped, bubbling or lifting paint, and pieces of concrete flaking off with rusted steel visible behind them.

We match the method to the diagnosis rather than applying one product to everything:

• Epoxy resin injection For structural cracks where the two faces need to be bonded back into a single element.
• Polyurethane injection Where the priority is stopping active water movement through the crack.
• Concrete cancer remediation Cutting back to sound concrete, exposing and cleaning the corroded reinforcement, treating it with an anti-corrosion primer, and reinstating with a polymer-modified repair mortar.
• HeliFix crack stitching Where cracking runs through masonry as well as concrete and the crack needs to be tied back together across its full length.
• Waterproofing and protective coatings So the repair is not undone by the same water that caused the problem.
• Joint installation Where movement needs somewhere to go rather than being resisted.

We look at the crack pattern, width and direction, check for drumminess and cover to the reinforcement, trace where water is entering, and look at the surrounding drainage and ground conditions. You get a written explanation of what is actually happening and a repair option costed against it — including, where it is honestly the case, being told that a crack is cosmetic and does not need structural work.

Book an inspection if you can see rust stains, if a crack is wider than about 2mm or has visibly grown, if there is drumminess or flaking, if water is coming through into the space below, or if cracking has appeared after nearby excavation or a change in drainage.

Concrete cracking often appears alongside other problems. We also carry out render crack repairs, leaking balcony repairs and restoration, and cladding repairs and restoration.

• HeliFix crack stitching
• Leaking balcony repairs
• Render crack repairs
• Cladding repairs