Concrete Post Upgrade versus Timber Posts - Deal Coast

A Deal Fencing working-contractor guide

The single biggest coastal-Kent fencing decision: concrete posts or timber posts on your boundary. I put in concrete on every new boundary I install in Deal, Walmer, Kingsdown, Mill Hill, Sholden, Great Mongeham and Ripple, and the reasons split three ways: lifespan, panel-swap ease, and storm survivability.

Lifespan

A treated softwood timber post at the ground line on the Deal coast has a working life of seven to twelve years before it starts to fail - the salt-air-laden rainwater capillary-wicking issue described in the spotting post rot guide. On Kingsdown clifftop the low end of that range is common. A concrete morticed post has a working life of forty-plus years. Over the lifetime of the property, the concrete post is put in once; the timber post is put in three or four times.

Panel-swap ease

Concrete morticed posts have a slot running the full length that a panel or a closeboard arris rail drops into cleanly. When a panel gets damaged - an easterly blows one out in January - you lift the top rail slightly, slide the damaged panel up and out, and drop a replacement panel back into the slot. Ten-minute job. A timber-post boundary means removing the arris rail or the featheredge boards to replace a panel, and you often need two people.

Storm survivability

The January easterly test. A concrete-post-and-gravel-board fence line where the concrete posts are set to 600mm on a standard boundary, or 750mm on a Kingsdown clifftop plot, will survive a Force 8 easterly with nothing more than a couple of blown panels that then swap easily. A timber-post boundary in the same storm loses posts, and once a post goes the flanking panels come down with it. Post-storm repair on a timber-post run is often 2-3x the cost of post-storm repair on a concrete-post run.

The cost gap

Concrete-post-and-gravel-board versus timber-post-only on the same length of new closeboard adds roughly 15 to 20 per cent to the up-front cost. Given the 3-4x lifespan multiple, the concrete-post spec is significantly cheaper per year of service across any timeframe worth planning around.

The only reason not to

Middle Street Conservation Area frontages where the visible spec has to match Georgian streetscape. On those plots the front boundary is often heritage-picket at 800mm to 900mm, and concrete posts do not fit the streetscape. Timber painted heritage-black or heritage-grey is the right call there, with the trade-off understood.