Landscaping fixings: screws, nails, bolts and why we choose them

Quick comparison

Start with the joint, not the screw box

A fixing connects parts so that the complete assembly can do its job. A fence board, a gate hinge and a deck support do not ask the same things of that connection. Before choosing a product, identify what is being joined, the condition of both materials, how the joint is loaded and where it will be exposed to moisture. Think about future access too: will a board need to be removed, or will the fixing become concealed? This is why a single screw type cannot sensibly cover every landscaping task. The aim is a compatible connection with documented performance where that is required.

Ordinary wood screws: useful, but not automatically structural

A suitable wood screw can secure non-structural timber components and can usually be removed later with the correct driver. Thread, head shape and length affect how it engages and seats. A countersunk head may suit a flush timber finish, while a bracket may require a different head. The important distinction is between general assembly and a connection whose strength forms part of a structural design. A screw described as multipurpose is not automatically a substitute for a tested structural fixing. Indoor screws should not be chosen for external work simply because they are already in the toolbox.

Nails: the right nail for the right connection

Nails remain useful for many timber assemblies. Smooth and profiled shanks, head shapes, lengths and finishes serve different purposes. The choice needs to match the board or connector and the installation requirements. A nail intended for a metal timber connector is a specific component of that connection; it should not be replaced with a convenient general-purpose nail. Equally, a nail gun is an installation tool, not evidence that its loaded nails suit the work. The question is not whether nails are always better or worse than screws, but which fastener the assembly requires.

Structural timber screws and TimberLOK-type products

Structural timber screws are intended for defined timber connections and are supported by product information. TimberLOK is a FastenMaster product name, rather than a universal description for every long timber screw. Other products have their own capacities, installation requirements and permitted uses. These fixings can be useful in substantial timber assemblies, but length alone does not establish suitability. Check the exact product, timber arrangement, engagement, spacing and exposure. A manufacturer's no-predrilling statement applies within its stated conditions; it should not be extended to every timber species, position or competing product. Overseas application examples also need checking against the requirements of the UK project.

Coach screws: a heavy-duty screw, not a through-bolt

A coach screw normally has a hexagonal head and a coarse wood thread. It can be used for suitable timber connections or compatible ironmongery, subject to the particular specification. Its thread grips the receiving material; it does not use a nut on the opposite side like a through-bolt. Pilot drilling may be required, depending on the timber and fixing instructions. Use the correct socket and seat the fixing without crushing the component. A coach screw used with a wall plug is only suitable where the complete plug-and-screw arrangement is approved for the substrate and load. Its substantial appearance is not a capacity rating.

Coach bolts, nuts and washers

A carriage or coach bolt passes through the joint and is tightened with a nut. A square shoulder beneath a typical domed head helps resist rotation in timber. This arrangement can suit specified timber or ironmongery connections when both sides are accessible. Washers provide a bearing surface beneath the nut or head where required. They need the correct dimensions and material; adding an arbitrary washer does not repair an unsuitable joint. Allow for the complete assembly thickness and follow the tightening requirements. Bolts, nuts, washers and the connected hardware should be selected together, including their suitability for outdoor exposure.

Decking screws and hidden clips

The fixings holding deck boards are not necessarily the fixings carrying the deck frame. Timber boards, composite boards, fascia pieces and framing can each need different products. Some composite systems use hidden clips with grooved boards; others use specified face-fixing screws or plug systems. Follow the board manufacturer's permitted combinations, fixing positions and movement allowances. A tidy hidden fixing is useful only if it remains compatible with the board and support. Do not change the fixing arrangement simply to hide more screw heads, or overtighten a board to remove a movement gap that the system needs.

Brackets, joist hangers and post connectors

A connector and its fasteners work as a system. The published capacity of a joist hanger or angle bracket depends on its specified installation, including the type, number and arrangement of fasteners. A general decking screw that fits a hole does not automatically deliver that performance. Some connectors permit particular nail and screw options, but those options must come from the relevant documentation. Check the fixing schedule before assembly, especially where timber will later hide the connection. A post shoe also needs an appropriate foundation and anchorage; the visible metal fitting alone does not establish that a post is adequately supported.

Fixings into brick, block and concrete

Solid brick, perforated brick, aircrete and concrete can need different fixing systems. Identify the actual substrate, not just its surface finish. A screw-and-plug combination, a concrete screw and an expansion anchor are different products with different installation conditions. Check substrate suitability, hole dimensions, embedment, edge distances and the load being applied. Existing masonry also needs to be sound enough for the proposed connection. Fixing a heavy gate to a weak or damaged pillar cannot be resolved merely by buying a larger screw. Connections supporting raised decks, guarding or substantial gates need an appropriately assessed arrangement.

Resin anchors and threaded rods

A bonded anchor uses a specified resin system with an approved rod or other component in a prepared hole. This is different from resin-bound driveway surfacing. The hole preparation, any sleeve required for hollow masonry, resin installation and curing conditions form part of the system. Follow the exact manufacturer's instructions before loading the fixing. A bonded anchor is not a universal repair for crumbling masonry, and its suitability depends on the substrate and connection. Where the anchorage is structural, the design should establish the product and installation requirements rather than leaving the choice to whatever cartridge is available.

Outdoor durability: coatings, stainless steel and treated timber

Rain, persistent dampness, timber treatments and salt exposure can affect metal fixings. A shiny finish or a description such as zinc plated does not by itself prove suitability for every outdoor environment. Hot-dip galvanised, proprietary coated and stainless-steel products have different specifications; the appropriate choice depends on the exposure and connected materials. Coastal locations deserve particular attention. The fastener should also be compatible with its bracket or connector. Do not assume that upgrading one component while leaving incompatible hardware beside it improves the complete connection. Use the manufacturer's corrosion guidance for the actual materials and site conditions.

How this applies to fences, sleepers, gates and decks

For fencing, distinguish the board-to-rail connection from the rail-to-post connection and the post foundation. For sleeper work, distinguish a decorative raised bed from a structure retaining a bank of soil. Longer screws do not turn an unspecified sleeper arrangement into a designed retaining wall. For gates, consider the complete hinge, post or pillar, latch and anchorage arrangement. For decking, distinguish boards, frame, supports and guarding. These examples explain why visually similar timber work can have different fixing requirements. A sensible quotation identifies the construction approach and resolves important connection details before they become difficult to inspect.

Installation and handover: the details worth checking

Once the fixing has been selected, follow its installation instructions for drilling, driver or socket, engagement and seating. Stop if timber splits, masonry breaks away or a fixing spins without holding; simply adding more fixings nearby may repeat the problem. Record the product references for concealed structural connections and photograph completed details where practical. At handover, ask what should be inspected and how accessible components can be maintained. Loose components, unexplained movement, splitting around a joint or significant corrosion warrant assessment. Maintenance access and a clear product record make future investigation easier than guessing what was installed.