Galvanised Bolt Down Round Post Support Base

Galvanised round post support base pressed from 2.0mm S235 structural steel and hot-dip galvanised for long-term corrosion protection, designed to bolt straight down onto concrete, paving, decking or another hard, level surface and hold a round timber post upright, without digging a hole or setting the post in postcrete.

The circular collar lifts the foot of the post clear of the surface it is mounted on and keeps the timber out of direct contact with concrete or paving. This allows the wood to expand and contract naturally and reduces the risk of moisture build-up and rot at the base. The hot-dip galvanised finish gives a durable, weather-resistant coating suited to permanent outdoor installations exposed to rain and damp ground, making this a fast, dig-free alternative to setting a post in postcrete; there is no need to dig a footing or mix and pour concrete around the post itself.

The base is supplied in two sizes, 80mm and 100mm, sized by collar diameter to suit the round post being fitted. Both share the same 150mm (5.91in) overall height and 2.0mm (0.08in) material thickness, so the choice between them comes down to matching the collar to the post: the 80mm size takes an 81mm (3.19in) collar diameter and weighs 0.85kg (1.87lb) per unit, while the 100mm size takes a 101mm (3.98in) collar diameter and weighs 1.18kg (2.60lb) per unit.

Key Features

• Pressed from 2.0mm (0.08in) S235 structural steel for a strong, rigid base plate and collar.
• Hot-dip galvanised finish for long-term corrosion protection on permanent outdoor installations exposed to rain and damp ground.
• Bolts straight down onto concrete, paving, decking or another hard, level surface, no digging or postcrete required.
• Available in two collar sizes, 81mm (3.19in) and 101mm (3.98in) diameter, to suit different round post diameters.
• Circular collar lifts the foot of the post clear of the ground, keeping timber out of direct contact with concrete or paving.
• Allows the post to expand and contract naturally, reducing moisture build-up and rot risk at the base.
• Fixing holes are pre-punched, ready for a straightforward bolt-down installation without further drilling of the bracket itself.
• Consistent 150mm (5.91in) overall height across both sizes, with unit weights of 0.85kg (1.87lb) for the 80mm base and 1.18kg (2.60lb) for the 100mm base.

Specification

Material: 2.0mm S235 structural steel. Finish: hot-dip galvanised. Two base sizes are available, sized by collar diameter to suit the round post being fitted; both share the same overall height and material thickness, and differ only in collar diameter and unit weight. Dimensions below are given in millimetres, with imperial (inch) equivalents alongside for reference.

Typical Applications

• Pergola and gazebo legs, as a bolt-down alternative to setting the post in concrete.
• Garden fence posts fitted onto an existing patio, driveway or concrete pad, where digging a fresh footing is not practical or desired.
• Decking support posts, keeping the base of the post raised clear of the deck surface to reduce moisture contact at the point where the post meets the timber structure below.
• Carport and canopy uprights that need a stable, permanent, above-ground fixing rather than a buried post.
• Replacing an existing post base, or converting a previously in-ground or post-mixed post to a bolt-down fixing on a hard surface.
• Any round timber post that needs a stable, elevated, bolt-down fixing to concrete or paving, rather than an in-ground or post-mix installation, useful wherever the supporting surface is already finished and cannot easily be dug into.

Installation Guidance

1. Choose the base size, 80mm or 100mm, to match the diameter of the round post being installed.
2. Position the base plate on the supporting surface, using the pre-punched holes in the base to mark the fixing points.
3. Bolt the base plate down: on timber decking or an existing wooden structure, fix using wood screws or coach screws around 10mm in diameter; on concrete or paving, fix using an M10 concrete anchor or an M10 concrete screw with a matching pilot hole.
4. Check the base is sitting level before final tightening, so the post it supports stands upright once fitted.
5. Drop the post into the collar and secure it through the pre-punched fixing holes in the collar.
6. Use a corrosion-resistant fixing to suit the galvanised finish of the bracket.

Order before 2pm Mon–Fri for same-day dispatch from our UK warehouse.