Concreting FAQs, Ballarat

A handful of things, and none of them can be judged from your kitchen table. The first is the area in square metres, since a bigger pour uses more material and more labour. The second is the finish: plain concrete is the simplest, while exposed aggregate, coloured and polished finishes add process and cost more. The third is what is already there, because breaking out an old slab, carting the rubble away and excavating a proper base all take time before a single wheelbarrow of new concrete arrives. The fourth is access, which around Ballarat can swing a job's price a long way, and the last is the ground itself, since reactive clay and disturbed old mining ground change what the footings and base have to do. That is why every job needs a site visit. Ring us with your suburb and roughly what you want done and we will get a local concreter to come and price it properly rather than throw you a number that changes the moment they turn up.

It matters more than people expect. Plenty of the elevated, frost-prone blocks around Buninyong, Mount Clear and Mount Pleasant are steep, which changes how the concrete gets from the truck to the formwork. If a truck can back up and chute straight in, that is the quickest and cheapest way. If it cannot, the mix has to be pumped or barrowed, which means more people and more hours. A steep site can also need extra formwork, steps or a stepped pour, and better thought given to where the water runs. The ground itself is the other variable: Ballarat's reactive clay and volcanic bluestone soils swell and shrink with the seasons and call for engineered footings and articulation, and in the older gold-era suburbs it pays to check for disturbed fill or old workings before the footings go in. A concreter who works your area already knows which of these applies before they arrive.

Yes, and it is the thing that most separates concreting up here on the goldfields from work down on the warmer flats. Ballarat sits around 435 metres, so it gets hard frosts through winter and the odd fall of snow. You do not pour into frost: fresh concrete that freezes before it has set is damaged for good, so a good crew watches the overnight minimums and holds off when frost is about. In the cold months the chemical reaction that hardens concrete runs much slower, so curing takes longer and finishing is timed to suit. Fresh pours are protected from frost with blankets or covers while they gain strength, and for driveways and paths that will cop repeated freezing and thawing an air-entrained mix with proper cover makes the surface far more durable over the years. A concreter who works Ballarat allows for all of this without being asked.

Grip is the thing to think about here, because a smooth trowelled surface turns slick when it is frosty or wet, and Ballarat gets plenty of both. Exposed aggregate, where the surface is washed back to reveal the stone, gives real grip underfoot and is the finish most people land on for driveways, paths and entries. A broomed finish, where the fresh surface is dragged with a broom to leave a fine texture, does the same job for less and is a sensible choice for a plain driveway. Sealing on top slows staining and adds a layer of protection, but the grip comes from the texture, not the sealer. Whichever finish you choose, the durability through the frosts comes from the mix and the cover over the steel underneath, not the look on top.

Sealing is not compulsory but it earns its keep in Ballarat's cold, wet climate, particularly on decorative and exposed aggregate finishes. A sealer slows staining from oil, leaves and general traffic, keeps colour from fading as fast, and adds a layer of protection that helps the surface shrug off wet winters. It is not permanent. It wears off over time and needs redoing periodically, and how often depends on the product used and how much sun and traffic the area cops. Ask your concreter what they have put down, because the product determines the reseal interval, and there is no single answer that fits every job.

The slab sitting on your own land generally does not need approval, but the part where your driveway crosses the footpath and nature strip to meet the road, the vehicular crossing, does need approval from the City of Ballarat, and the Council has its own specifications for how it is built. That covers the width, the profile, the materials and how it ties into the kerb. Stormwater and drainage can also come into it on some blocks, especially around Lake Wendouree and the low-lying areas where water has to go somewhere sensible. A concreter who works Ballarat will usually know the local requirements and how to arrange the crossing, but the approval itself sits with the Council, so it is worth raising early rather than after the pour.

Walking is usually fine within a day or so, once the surface has hardened enough not to mark. Driving is a different matter. You should generally keep cars off a new driveway for about a week, and heavier vehicles such as trucks, caravans or a loaded trailer for longer again. Concrete keeps gaining strength for weeks after it looks finished, so the surface being hard underfoot does not mean it is ready to carry a car. Your concreter will give you a specific time based on the mix, the thickness and the weather on the day. In the cooler months the reaction that hardens concrete runs slower, so a Ballarat winter pour will sit at the longer end.

Winter is fine, it just moves more slowly. Cold slows the chemical reaction that hardens concrete, so curing takes longer and the concreter may adjust the mix or the finishing schedule to suit. Rain is the bigger problem, and Ballarat gets its share of wet weather, while a hard frost will stop a pour outright. Water landing on a fresh surface before it has set can weaken and mark the finish, so pours get postponed when the forecast is poor. It is frustrating to have a job pushed back a few days, but a concreter who reschedules you because of rain is doing right by your slab. Trying to pour through a downpour to keep to a date is how you end up with a surface that never looks right.

All concrete cracks to some degree. It shrinks as it cures and it moves with temperature and ground conditions, and it has very little ability to stretch. The job of a good concreter is not to stop cracking outright, which cannot be done, but to control where it happens using control joints, correct steel and a properly compacted base. Fine hairline cracks are normal and cosmetic and are nothing to lose sleep over. What is worth a look is a wide crack, a crack with a step or height difference across it, or a crack that keeps growing, because those usually point to something moving underneath, poor base prep, or drainage that has failed. Ballarat's reactive clay and bluestone soils are a common culprit here, swelling in the wet and shrinking in the dry, which is why control joints, the right steel and engineered footings matter so much locally. If you are seeing a crack like that, get someone to look at it rather than filling it and hoping.

It depends entirely on what is going on top of it. A residential driveway carrying cars is typically around 100mm with reinforcing mesh through it. Anything carrying heavier loads, a truck, a caravan, a boat trailer or an industrial hardstand, needs more thickness and heavier reinforcement. Ground conditions change it too. Ballarat's reactive black clay and bluestone soils move with the seasons and can call for a thicker slab, heavier steel and articulated or engineered footings rather than a default pour. Your concreter should specify the thickness and steel for your particular job rather than pouring a standard, and it is a perfectly fair question to ask when they quote you.

Often, yes. If the existing slab is structurally sound, not badly cracked and has not dropped or moved, resurfacing is usually cheaper and faster than demolition and a fresh pour, and it saves you the mess of breaking the old one out. If the slab has deep cracks, a step across a crack, or drainage that has failed, an overlay just puts a new surface over the same problem and it will come back through within a season or two. Someone needs to stand on it and look at it to tell you honestly which situation you are in. It is one of those calls that cannot be made from a photo.

The whole city and its surrounds. That takes in Wendouree, Sebastopol, Alfredton, Delacombe, Lucas and Mount Pleasant, through Ballarat East, Soldiers Hill, Golden Point and Canadian, out to Mount Clear, Buninyong and Miners Rest, and across to Redan, Black Hill, Brown Hill and around Lake Wendouree. Our suburbs page lists everywhere we work in detail.