Concreting on sloping and hillside blocks

Living on a slope

The closer you get to the Dandenongs, the steeper the blocks become. Houses sit above or below the street, driveways climb or plunge, back yards fall away in terraces, and stormwater runs hard after rain. Concrete on these sites must do more than look good. It has to grip, drain, hold its shape and be safe to walk and drive on.

Steep driveways

On steep drives we: – use a heavy broom, grooved or exposed aggregate finish for traction – shape the transitions at the kerb and the garage so cars do not scrape – thicken the slab where vehicles brake and turn – set saw cuts to manage stress along the slope – add grated drains at the bottom, and part way down on long drives – protect the edges so runoff cannot undermine them

Benched pads

Level areas for parking, a shed, a patio or a play space often need cutting into the slope and filling on the low side. The cut is held by a retaining wall with drainage behind it, the fill is compacted in layers, and the slab is designed for any ground that is not natural.

Stepped paths and landings

Paths on steep blocks become a series of ramps, steps and landings. We set every riser to the same height, make treads deep enough for a full foot, add landings where a path turns or where doors open, and allow for handrails.

Water on a slope

Water is the biggest risk on hillside blocks. Runoff from above can wash under slabs, scour edges and flood garages. We use cut-off drains across the top of slabs, grated drains at the bottom, falls that direct water to pits, and connections to the property's legal point of discharge.

Access for trucks and pumps

Steep narrow streets and high or low blocks can make truck access tricky. A concrete pump with a boom or a long line usually solves it. We assess access on the site visit.

Engineering and permits

Large cuts, tall retaining walls and slabs on fill may need engineering, and walls over a certain height need a building permit. Parts of Upper Ferntree Gully, Upwey and the hills also carry bushfire or vegetation overlays. We check what applies.

Fixing problem slopes

Common call-outs include driveways too steep to use in rain, cars scraping at the kerb, washouts beside driveways, and paths with uneven steps. Rebuilding with proper grades, finishes and drainage fixes them.

Quotes

We take levels across the site and quote each part separately.

Reading a sloping site

Every sloping block is different. Some rise gently from the street; others fall away sharply behind the house. Some have rock close to the surface; others have deep clay or old fill. On a site visit we take levels across the block, note where water enters and leaves, look at the soil in a test hole, and work out how trucks or a pump can reach the work. That information shapes everything from the driveway grade to the height of retaining walls.

Cut, fill and benching

Creating level space on a slope means cutting into the high side, filling the low side, or both. Cuts need retaining walls to hold back the soil; fill needs to be compacted properly or it will settle under the slab. Benched pads for parking, sheds and outdoor areas are some of the most common jobs we do in the foothills.

Stepped slabs and split levels

Sometimes it makes more sense to step a slab than to force a single level. A patio might be split into two levels joined by a few steps, or a driveway might have a flatter landing partway up. Stepped designs often reduce wall heights and cost.

Driveway grades and transitions

Steep driveways need careful transitions where the grade changes, especially at the kerb and garage. We design these so cars do not scrape and the driveway remains comfortable to walk on.

Water on slopes

Slopes concentrate water. A sloping driveway can become a channel in heavy rain, and water running through the soil can build up behind walls and slabs. Cut-off drains, ag drains behind walls and pits connected to stormwater are essential on most hillside jobs.

Safety on steep surfaces

Grippy finishes, handrails on steps, and clear edges matter on slopes. We avoid glossy sealers on steep areas and recommend anti-slip additives.

Access and equipment

Steep or tight sites often need a concrete pump, small excavators, or barrows. Planning access early keeps the job on schedule and protects the property.

Working with engineers

Retaining walls over certain heights, slabs on deep fill, and work near boundaries or structures often need engineering. We work with engineers to get designs that are practical to build.

Erosion and edges

Bare soil beside new concrete on a slope can wash away, undermining edges. We recommend planting, mulch or rock beside slab edges and can build edge beams or small walls where scour is likely.

Foothill ground, rain and councils

Ferntree Gully sits where the Knox plains run up into the Dandenong Ranges. Below the lawns on the lower streets you usually find heavy grey and orange clay that holds water through winter and splits open in a hot February. Higher up toward Upper Ferntree Gully, Upwey and The Basin, the soil is a stony, brown hillside clay over weathered rock, and the slopes send a surprising amount of water downhill every time it rains. Old cut-and-fill from earlier house builds adds another variable. We dig a test hole on every property, take the soft material out, rebuild with compacted crushed rock chosen for what we found, and shape the surface so water always has somewhere to go.

Inside your own boundary, most driveways, paths and patios need no permit. The crossover, kerb and council footpath always do, and that consent comes from Knox City Council for most of our area or the Shire of Yarra Ranges for Upwey and parts of Upper Ferntree Gully, Lysterfield and The Basin fringe. House slabs, large garages and many retaining walls go through a building surveyor with engineering. Bushfire and vegetation overlays affect parts of the hills. Your quote names whatever applies.

What our Ferntree Gully quotes spell out

You will not get a single number scribbled on a business card. Our written quote breaks the job into the pieces that actually drive the outcome: the area in square metres, breaking out and disposing of whatever is there now, how far down we dig, the class and depth of crushed rock, slab thickness and the steel inside it, the finish or stone blend you chose, the joint plan, each drain, pit and length of pipe, step and edge work, sealing, and any Knox or Yarra Ranges paperwork. If the site needs a line pump, a long barrow run or protection for a neighbour's driveway, that is listed too.

We keep square-metre rates off this website on purpose. In the foothills, the work hidden below the finished surface varies hugely between two blocks in the same street: one might be firm and flat, the next steep, wet and full of old fill. Pricing sight unseen means guessing, and a guess ends up either padded or short. After a visit we can price the real job.