Galvanised Coach Bolts for Retaining Walls, Fencing and Outdoor Timber Builds

Shop galvanised coach bolts from I Got Wood for outdoor timber builds in Victoria, with M10 and M12 sizes available online.

Galvanised coach bolts create through-bolted timber connections using a smooth cup head, square neck and nut. We stock multiple M10 and M12 lengths for outdoor projects, but the correct diameter and length must come from the connection design rather than guesswork.

What Are Coach Bolts Used for Outdoors?

A coach bolt passes through the connected materials and is tightened with a nut. The square section beneath its rounded head bites into the timber, helping prevent the bolt from turning while the nut is tightened. This arrangement provides a neat, exposed face and firm clamping across the joint.

Common applications can include fence posts and rails, timber sleepers, garden structures, pergolas and timber-to-bracket connections. Suitability still depends on the loads, timber dimensions, treatment, exposure and approved construction details. A galvanised coating supports outdoor use, but it does not make one bolt appropriate for every structural or environmental condition.

Our online coach bolt product range includes M10 lengths from 50 mm to 300 mm and M12 lengths from 100 mm to 200 mm. Each listed bolt comes with one nut, while matching washers are available separately.

Choosing Galvanised Coach Bolts for Timber Connections

Choose galvanised coach bolts by checking the complete joint, not simply the thickness of one timber member. The bolt must pass through every timber section or bracket, plus the washer and nut, while providing adequate thread engagement.

Before ordering, confirm:

• Specified diameter: Use the M10 or M12 size shown in the design, engineering details or manufacturer’s instructions.
• Required length: Add the thickness of every connected component and allow for the washer, nut and thread engagement.
• Washer selection: Place the specified washer beneath the nut to distribute pressure and reduce localised crushing.
• Material compatibility: Check the bolt coating against the timber treatment, connected metal and site exposure.
• Quantity and spacing: Follow the approved fixing schedule rather than estimating bolt numbers on site.

For retaining walls and other structural work, obtain professional advice where the design does not nominate the fixing. Victoria’s building regulator explains when a building permit may be required, including circumstances involving retaining walls and work near property boundaries.

Installation Checks That Protect the Connection

Accurate preparation helps the connection fit and tighten correctly. Mark the hole position from the approved plans, drill straight and use the specified hole diameter. Fit the bolt without damaging its coating, install the washer and nut, then tighten it evenly. Excessive tightening can crush timber fibres and weaken the connection rather than improve it.

Inspect accessible fixings during routine maintenance. Movement, corrosion, damaged timber or a loose nut may indicate that the connection or surrounding structure needs assessment. Outdoor exposure varies, particularly where moisture becomes trapped or the site is coastal, so seek project-specific advice instead of relying on a generic installation rule.

We also supply timber sleepers and a broader hardware range, allowing builders, landscapers and DIY customers to coordinate materials and fixings before ordering.

Order the Correct Fixings from I Got Wood

We supply galvanised coach bolts online and from our Bayswater store for suitable fencing, landscaping and outdoor timber projects. Review the project documentation first, then select the required gauge, length, nuts and washers from the verified product options.

Need help finding a listed size? Send our team an enquiry with your material thicknesses, connection details and required quantity, or order the nominated option online for your next build.

Optimized by: Netwizard SEO