A fence on a slope is built one of two ways. A raked fence follows the ground, with the rails running parallel to the fall and the top of the fence sloping with the block. A stepped fence stays level in sections and drops down the hill one panel at a time. A steady, even fall usually suits raking, and a steep or uneven fall usually suits stepping. Plenty of Illawarra blocks, especially along the escarpment, have a fall on them, so most fence jobs here involve this choice.
Should you rake or step a fence on a slope?
Raking works best where the ground falls at a consistent angle, such as a back yard that drops evenly from the house to the rear boundary. Every paling or sheet follows the ground, so there is no gap underneath, and the fence looks like it belongs on the block. On ground that dips and rises, a raked fence follows every dip, and the top line ends up wavy.
Stepping works on steeper or more broken ground. Each section is built level, with a post at every step, and the fence drops in stages. Pre-made panel and sheet systems are normally installed this way, because the panels are made to hang level.
Neither is the correct answer on its own. The fall, the material and how the fence looks from the neighbour's side decide it, and the decision is made on the block with a level in hand.
What does a stepped fence leave at the bottom?
Each step leaves a wedge-shaped gap under the downhill end of the panel. On a gentle slope the gap is small. On a steep one it can be wide enough to let a dog through or to look unfinished from the street.
There are three usual ways to close it:
- A kickboard or plinth board fixed along the bottom of each section.
- Cutting the ground back so the fence sits closer to the soil.
- Building up the low side with a sleeper or a small retaining edge.
Raising or lowering the ground changes drainage, so it is worth checking where the water goes before anyone starts digging. A raked fence avoids the gap altogether, which is one reason it is the first choice on a steady fall.
How do you hang a gate on a sloping fence line?
A gate has to clear the ground through its whole swing. If the gate swings towards ground that rises, it drags unless it is hung high enough to clear or the bottom rail is angled to match. Hanging it so it swings over the lower ground avoids the problem.
The gate frame is braced and hung on solid posts, because a gate moves more than any panel on the run. For a fence to be exempt development in NSW, gates must not open outwards. On a sloping front or side boundary that means working out the swing inwards before the posts go in, not after.
Does a slope change what a fence costs?
Yes. The per-metre figures in the fencing cost guide assume flat, clear ground. Once the line runs up a slope, the fence has to step or rake, and each step means more setting out and more cutting. Hard or rocky ground slows the post holes. A fence that also holds back a garden bed or a change in level is a different job again, sometimes with engineering behind it.
Fencing on top of a retaining wall needs the posts and the load worked out so the fence is not slowly pushing the wall over. That calculation is part of the quote, which is why a fence on a slope is priced after someone has walked the line. The fencing page covers the timber, picket and Colorbond options and what is included.
Do you need approval to fence a sloping block?
A slope does not change the approval rules. The NSW Planning Portal lists the exempt development standards for fences. In residential zones R1 to R4 and RU5, side and rear boundary fences can be up to 1.8 metres high (1.2 metres if masonry) without planning approval. Fences on bushfire-prone land must be non-combustible or hardwood, and exempt development does not apply to land on the State Heritage Register.
Where the ground falls, ask your council how the height is measured along the fence line before you settle on panel heights. If the fence separates your lot from a neighbour, the Dividing Fences Act 1991 applies as well, and the Planning Portal page points to it.
A privacy screen fixed to the top of a fence adds to the total height and the wind load, which is covered in the privacy screen cost guide.
To get a fence priced on a fall, call Dave on 0414 007 351 or send the contact form. He will walk the line, work out whether it should be raked or stepped, and quote it on that basis.
Want a hand with this at your place? Get a free quote or call 0414 007 351.
