Concrete Under-Fence Plinths: Plain Grey vs Charcoal — Which Should You Choose?

One of the most common problems with Colorbond fencing is the gap at the bottom — the space between the bottom of the fence sheet and the ground. This gap lets animals in, allows weeds to grow through, and can look untidy. The solution is a concrete under-fence plinth.

At Wallan Fencing and Timber Supply, we stock concrete under-fence plinths in two colours: plain grey and charcoal. Both are 2360mm long × 50mm thick and are designed to sit in the ground beneath your Colorbond fence sheets.

What Is an Under-Fence Plinth?

An under-fence plinth (also called a concrete fence base or fence footing plinth) is a precast concrete panel that sits in a shallow trench beneath the fence line. The Colorbond fence sheet sits on top of the plinth, eliminating the gap between the sheet and the ground.

Unlike timber plinths, concrete plinths don't rot, warp, or get attacked by termites. They're a permanent solution that requires no maintenance.

Plain Grey vs Charcoal: Which Should You Choose?

Plain Grey

Plain grey is the standard concrete colour — a neutral mid-grey that blends with most soil and paving colours. It's the most common choice for residential fencing across Mitchell Shire and suits most Colorbond fence colours.

Best for: Most residential applications, neutral colour schemes, budget-conscious projects.

Charcoal

Charcoal is a darker grey that provides better contrast against light-coloured fence sheets (like Surfmist or Shale Grey) and blends more naturally with dark fence colours (Monument, Night Sky, Ironstone). It has a more premium appearance and is increasingly popular in newer estates around Wallan, Beveridge, and Donnybrook.

Best for: Dark Colorbond colours, modern homes, premium finishes, light-coloured paving.

Specifications

Feature	Detail
Length	2360mm
Thickness	50mm
Height	Typically 150–200mm above ground
Material	Precast concrete
Colours	Plain grey, Charcoal

Installation

1. Excavate a shallow trench along the fence line, approximately 100mm deep and 150mm wide.
2. Set the plinths in the trench, butting them end-to-end. Check they're level and in line with a string line.
3. Backfill around the plinths with compacted soil or gravel to hold them in position.
4. Set fence posts through or alongside the plinths as required.
5. Hang fence sheets so the bottom edge rests on top of the plinth.

The plinth should project 100–150mm above finished ground level so the fence sheet clears the ground with a small gap for drainage.

How Many Plinths Do You Need?

Each plinth is 2360mm (2.36m) long.

Number of plinths = Total fence length (m) ÷ 2.36, rounded up

For a 30m fence: 30 ÷ 2.36 = 12.7 → 13 plinths

Available at Wallan Fencing and Timber Supply

We stock concrete under-fence plinths in plain grey and charcoal at our Wallan yard, with same-day pickup available. We supply homeowners, tradies, and builders across Mitchell Shire — including Kilmore, Broadford, Seymour, Beveridge, Craigieburn, and Donnybrook.

Call us on 0431 193 102 or get a quote online.