Very few blocks in Brisbane and the surrounding hills are perfectly flat. When the ground falls away along a boundary, a fence built as if the site were level will either leave awkward gaps underneath or look crooked against the horizon. The fix is to build the fence to suit the slope: and there are two main ways to do that: raking and stepping. Here is how each one works and how to choose.
The quick answer
Raked: the fence follows the ground on an angle (posts stay vertical, the panel rails tilt). No gaps underneath, so it is neat and pet-friendly, and it suits smooth, gradual slopes.
Stepped: the panels stay level and step down like a staircase. It handles steeper falls, but leaves a triangular gap under each panel that you close with a plinth or sleeper.
Aluminium suits both methods: the right choice comes down to how much the ground falls and the look you want.
Fence height on a slope is measured above natural ground level, and a fence on top of a retaining wall counts as their combined height.
Why a sloping block needs a different approach
A fence panel is a rigid rectangle. Put a run of level rectangles along ground that falls away and something has to give: either the panels tilt to follow the ground, or they stay level and a wedge-shaped gap opens up beneath them. On a sloping block the installer has to decide, panel by panel, how to manage that fall: keeping the fence looking straight along the top, closing the gaps at the bottom, and allowing for water to run downhill along the fence line.
Get it right and a sloping fence looks intentional and tidy. Get it wrong and you end up with daylight under the panels (an easy escape route for pets and a way in for pests), an uneven top line, or water pooling against the posts. That is why the two proven methods (raking and stepping) exist.
Raked (raking) fences
A raked fence follows the slope of the ground. The posts stay perfectly vertical, but the panel is built so the horizontal rails tilt to match the incline: so the whole panel sits parallel to the ground rather than level. Because the fence hugs the ground the entire way, there are no triangular gaps underneath.
Raking works well when:
The slope is gradual and consistent: a smooth, steady fall along the boundary.
You want the cleanest look, with the fence flowing down the slope in one continuous line.
You need to keep pets in and pests out: with no gap under the panels, there is nothing to dig under or squeeze through.
Aluminium and tubular fences rake particularly well, which is one of the quiet advantages aluminium has over a solid sheet fence on a sloping site. On a very steep or sharply changing slope, though, there is a limit to how far a panel can be raked before it looks awkward: and that is where stepping takes over.
Stepped fences
A stepped fence keeps each panel perfectly level and drops it down a step from the one before, like a flight of stairs running down the hill. It is the go-to method for steeper falls and for ground that changes grade, because each panel is simply set at the height that suits its section of the boundary.
The trade-off is the triangular gap that opens up under the low end of each level panel. That gap is normally closed with a concrete plinth or a treated timber sleeper run along the base of the fence: which seals the gap, keeps pets and pests where they belong, holds back soil and mulch, and protects the bottom of the fence from wet ground. On some blocks a low retaining edge does the same job while tidying up a change in level.
Raked vs stepped: quick comparison
| Raked | Stepped | |
|---|---|---|
| How it looks | Follows the ground in one smooth line | Level panels stepping down like stairs |
| Gap underneath | None: hugs the ground | Triangular gap, closed with a plinth or sleeper |
| Best for | Gradual, even slopes; pet owners | Steeper falls; ground that changes grade |
| Pet & pest proof | Excellent out of the box | Excellent once the plinth is added |
Many real fences use a mix: raking the gentle sections and stepping where the ground drops away sharply.
What about the gap under the fence?
On a raked fence, the panel follows the ground, so the gap looks after itself. On a stepped fence, closing the gap is the main finishing job, and there are three common ways to do it:
Concrete plinth. A precast or poured concrete strip under the panel: the most durable option and a clean, hard-wearing base.
Timber sleeper. A treated pine or hardwood sleeper along the base: quick to install and easy to match to a garden setting.
A low retaining edge. Where one side sits higher than the other, a low retaining sleeper or wall holds the soil back and squares up the base of the fence at the same time.
Whichever you choose, closing that gap is what keeps a dog in the yard, stops soil and mulch washing under the fence, and gives a stepped fence a finished, deliberate look.
Height rules on a sloping or retained block
Slopes and retaining walls change how fence height is measured, so they are worth a mention before you build. In Queensland, fence height is measured above natural ground level, and a fence built on top of a retaining wall is assessed as the combined height of the wall plus the fence. A 900 mm retaining wall with a 1.5 m fence on top is 2.4 m combined: over the 2 m mark where building approval is generally required.
Some councils make specific allowances for sloping sites: Moreton Bay, for example, allows a mean height of up to about 2.1 m without approval by averaging the fence along an uneven boundary. The rules vary by council and by address, so our guide to Queensland fence height and council approval rules is the place to check the detail: and always confirm your own block with your local council before you build.
How FY Fencing handles sloping blocks
Our aluminium panels are made to order and built to suit your site: including sloping ground. That means we can rake the panels to follow a gradual fall, or supply level panels to step down a steeper slope, and advise on the plinth or sleeper that finishes the base. Because the panels are custom-built rather than a one-size stock item, they can be tailored to the fall along your particular boundary. Hilltop and ridgeline blocks tend to catch the wind as well as the fall, and on those boundaries the panel spec matters too: our guide to slat spacing and posts for windy blocks covers what changes on an exposed site.
The Horizontal Slats Fence is a popular choice on sloping blocks for its clean, modern line, and the same made-to-order approach applies across the range. To plan your project, browse our aluminium fencing range, compare slat, picket and blade styles, or read how orientation plays out on horizontal vs vertical slat fencing. For pricing, see our guide to aluminium fencing costs in Brisbane.
The surest way to price a sloping job is a site measure, because the fall along the boundary decides how much raking, stepping and plinth work is involved. Send us the details and we will work it out with you.
Frequently asked questions
Can you put an aluminium fence on a sloping block?
Yes. Aluminium is one of the easier materials to fence a slope with. On a gradual fall the panels can be raked to follow the ground; on a steeper fall they are stepped down and the gap underneath is closed with a plinth or sleeper. Our panels are made to order to suit sloping sites.
What is the difference between a raked and a stepped fence?
A raked fence follows the slope: the posts stay vertical but the panel tilts to match the ground, so there are no gaps underneath. A stepped fence keeps each panel level and drops it down a step at a time like a staircase, which leaves a triangular gap under each panel that is closed with a plinth or sleeper.
How do you fill the gap under a fence on a slope?
On a stepped fence the gap is normally closed with a concrete plinth, a treated timber sleeper, or a low retaining edge along the base. This seals the gap, keeps pets in and pests out, holds back soil and mulch, and protects the bottom of the fence. A raked fence avoids the gap altogether because it follows the ground.
Which is better: raked or stepped?
Neither is universally better; it depends on the slope. Raking gives the cleanest look and no gaps, and suits gradual, even falls. Stepping handles steeper ground and grade changes. Many real fences use both: raking the gentle sections and stepping where the ground drops away sharply.
Do fences on a slope or retaining wall need council approval?
Height is measured above natural ground level, and a fence on a retaining wall is assessed as the combined height of the wall plus the fence: so a fence that is fine on flat ground can tip over the 2 m approval threshold once a retaining wall is added. Rules vary by council and address, so always confirm your block with your local council. Our Queensland fence height guide covers the detail.
Can aluminium slat panels be made to follow a slope?
Yes. Because our panels are made to order, they can be built to rake with a gradual slope or supplied level for a stepped install, and tailored to the fall along your particular boundary. A site measure is the best way to work out the right approach and price.
A note on height and retaining walls. On a sloping or retained block, fence height is measured above natural ground level and a fence on a retaining wall counts as the combined height of both. Approval requirements vary by council, zone and address. Before you build, confirm the rules for your specific block with your local council.
Working out what your fence line needs? Tell us the run and the height and we will quote it, supply-only or installed.
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