24/05/2025
Why Concrete Matters More Than You Think đ¤
Concrete may not be the most glamorous part of your build, but itâs one of the most important. Everythingâfrom your bathrooms and kitchen to the structure itselfârelies on a solid foundation. If the concrete isnât done right, problems can be costly and difficult to fix.
Concrete comes in different strengths (measured in MPa), and for residential homes, 20MPa, 25MPa, and 32MPa are common. Itâs also mixed to a certain consistency, called a âslump,â and typically includes 20mm stones (aggregate). Some contractors add extra water on-site to make it easier to work withâbut this weakens the mix and reduces durability.
Once poured, concrete must be properly vibrated to remove air pockets and ensure strength. It also needs to fully cover the steel reinforcementâideally by at least 50mmâto prevent rust and long-term damage like concrete cancer.
For slab floors, a plastic barrier is placed underneath to stop moisture from rising through. Itâs important this is installed correctly. Strip footings donât require this plastic but still need proper strength, vibration, and coverage.
Finishing matters, too. Slabs should be level, with small step-downs in wet areas, garages, and verandahs for drainage. Garages done to a high standard will also have a slight slope to help with cleaning.
Lastly, curingâhow the concrete setsâis often overlooked but crucial. Good practice includes covering the concrete to retain moisture and slow the drying process, making the slab stronger. Ideal weather conditions also help: avoid extreme heat, wind, or rain when pouring.
Even with the best preparation, small cracks can still appear. These are usually cosmetic and donât affect performanceâbut they do highlight the importance of quality from the start.
