Ripping out a serviceable fence because it is short is usually a waste. A fence extension adds height to the fence you already have, turning a 1.5 or 1.8 metre boundary into a proper privacy screen for a fraction of the cost of replacing it. First, though: the height rules: and, on a shared boundary, your neighbour’s okay.
The quick answer
A Queensland fence over 2 metres generally needs building approval: and the total includes the extension.
Some councils treat open-style screening above a solid fence more leniently: rules vary.
On a shared dividing fence, get your neighbour’s written consent before attaching anything.
Aluminium slat extension panels are the most durable option: FY custom-sizes them to your post spacing.
Why people add height to a fence
The most common trigger is a two-storey house going up next door: a 1.8 m fence does nothing once an upstairs window looks over it; even 300 to 600 mm pushes that sightline back. The other regulars: dogs that jump or react to passers-by (a taller, solid screen removes the trigger and the escape route), exposed street-facing yards, and road noise: more fence will not silence traffic, but it takes the edge off.
The rules first: heights, approvals and neighbours
1. The height rules. A fence up to 2 metres above natural ground level can generally be built in Queensland without building approval. The catch for extensions: the 2 m is a total: councils such as Brisbane count fences, screens and retaining walls together, so a 500 mm topper on a 1.8 m fence lands at 2.3 m and in approval territory. Some councils allow open-style screening (slats or lattice with visible gaps) above a solid fence, but details differ: our guide to Queensland fence height rules covers the limits; always confirm your address with your council.
2. The neighbour rules. A fence on a shared boundary is a dividing fence, owned jointly no matter who paid. Queensland Government guidance is clear: consult your neighbour before any work that alters the fence, and get written consent before attaching anything to it: lattice and screens included. Neighbours normally split a “sufficient” fence (up to 1.8 m) half each, but extra height for your privacy is generally your cost: our Notice to Contribute and cost-sharing guide explains who pays for what.
Fence extension options compared
There are four realistic ways to get more height:
| Option | Durability | Look | Cost & effort |
|---|---|---|---|
| Aluminium slat extension panels | Excellent: will not rust, rot or warp | Clean, modern; matches the fence below | Mid-range; bolt-together, DIY-friendly |
| Timber or PVC lattice | Poor to fair: sags, splits, rots or fades | Traditional; dates quickly | Cheapest up front, shortest life |
| Freestanding privacy screens | Good in aluminium; varies elsewhere | Decorative; screens one spot only | Mid-range; own footings, fence untouched |
| Full fence replacement | Best: built for the full height | Cleanest result; no join line | Highest cost; right call for tired fences |
Qualitative guide only: actual costs depend on fence length, post condition and access.
Retrofitting slat extensions to a Colorbond or timber fence
Aluminium slat extensions are usually fitted one of two ways:
Post extension brackets. If the existing steel or timber posts are sound, brackets bolt to each post top and carry a slat panel above the fence line: the tidiest, cheapest route on a healthy Colorbond fence.
New posts behind the fence. Where the old posts are past their best, slim aluminium posts set on your side just behind the fence carry the panels instead, so the extension bears its own weight and wind load (still talk to your neighbour first).
What makes or breaks the result is panel sizing. Colorbond bays, hardwood fences and brick-pier fences run different post spacings, and off-the-shelf panels rarely land on them. Custom sizing is FY’s strength: each panel is made to your measured bay widths and height, so the slat lines run continuously along the fence. Powder-coated Black, Monument and White sit well against common Colorbond colours: see our aluminium fence colours guide.
Choosing the slat gap: privacy versus airflow
Slats set tight give a near-solid screen; a 5 to 10 mm gap keeps most of the privacy while letting breeze through: welcome in the Queensland heat. Helpfully, viewed from an angle (exactly how a two-storey window sees your yard) the slats overlap and the gaps all but close. And where your council wants open-style screening above 2 m, a wider gap can be what keeps the extension compliant. Our slat spacing guide shows what each gap looks like in practice.
When replacing beats extending
An extension adds height, weight and wind load: so the existing fence has to be worth building on. If a timber fence is leaning, soft at ground level or on its second decade, bolting more fence on top only speeds up the failure. Better to replace the lot with full-height aluminium fence panels: one structure engineered for the job, no join line, no repeat spend. Rule of thumb: ten good years left, extend; needs replacing within five, put the money towards a new full-height fence.
How DIY-friendly are bolt-together extensions?
Very: with sound posts, fitting brackets and bolting on pre-made slat panels needs little more than a drill, a level and a spare Saturday; the hard part (setting posts) is already done. Panels arrive powder-coated and made to size: no cutting, no painting. Our step-by-step installation guide covers the process, and professional installation is available too.
Order through our online shop, collect from the Slacks Creek yard in Logan, or have it delivered across South East Queensland: Brisbane, Logan, Ipswich, Gold Coast, Sunshine Coast, Toowoomba and surrounds. Outside SEQ it is pickup or your own freight, and returning customers earn loyalty discounts.
Frequently asked questions
Can I add height to an existing fence in Queensland?
Yes, if the finished height stays within the rules. Up to 2 metres generally needs no building approval, and the total includes the extension. Over 2 metres usually means approval, and a shared dividing fence needs your neighbour’s consent first.
Do I need council approval for a fence extension?
Not if fence plus extension stays at 2 metres or under. Above that, building approval is generally required, though some councils treat open-style screening more leniently. Rules vary, so confirm your address before ordering.
Do I need my neighbour’s permission to extend a shared fence?
Yes. A boundary fence is jointly owned, and Queensland Government guidance says to consult your neighbour before altering it and get written consent before attaching anything, lattice included. Extra height benefits you, so the cost is normally yours.
Can you put aluminium slat extensions on a Colorbond fence?
Yes: it is a very common retrofit. Sound steel posts take extension brackets that carry slat panels above the sheeting; otherwise slim aluminium posts behind the fence do the job. Black, Monument and White finishes sit well against common Colorbond colours.
What is the best fence extension for privacy?
Aluminium slat panels with a tight gap give the best mix of privacy and lifespan: no rotting, sagging or warping like timber lattice, and the gap can be tuned for privacy, airflow or an open-screening look. Overlapping slats screen elevated views especially well.
Are fence extensions DIY-friendly?
Generally yes. Bolt-together aluminium panels fit sound existing posts with basic tools: no post holes, no concrete, no painting. Panels come made to your bay widths and height: a measure, drill and bolt job.
A quick note before you build. This article is general information, not legal or building advice. Height limits and approvals differ between Queensland councils and change over time: confirm the rules for your address, and get neighbour consent in writing before touching a shared dividing fence.
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