Screws

Choosing the Right Screws for Your Project

At County Building Supplies, we supply screws for a wide range of building, carpentry, joinery, plasterboarding and general maintenance projects. Whether you're fixing timber, installing plasterboard or securing materials to masonry, choosing the correct screw type, size and finish is important for a reliable and long-lasting fixing.

Our range includes wood screws, coach screws, collated screws, drywall screws, masonry screws, and screw caps and washers for trade professionals and DIY customers.

Which Type of Screw Do I Need?

Different screws are designed for different materials and applications. Before choosing a screw, consider what you're fixing into, what you're attaching and whether the installation will be indoors or outdoors.

• Wood screws: Designed for fixing timber and suitable wood-based materials. Commonly used for carpentry, joinery, timber framing and general woodworking.
• Coach screws: Heavy-duty screws typically used for suitable timber connections, including fencing, gates and timber structures.
• Collated screws: Supplied in strips for use with compatible automatic-feed screwdrivers, helping speed up repetitive fixing tasks.
• Drywall screws: Designed for fixing plasterboard to suitable timber or metal framing, depending on the screw specification.
• Masonry screws: Designed for suitable fixing applications involving brick, block or concrete, subject to the product and substrate requirements.
• Screw caps and washers: Accessories used to improve the appearance, bearing surface or performance of suitable screw fixings.

Choosing the Right Wood Screws

Wood screws are among the most commonly used fixings in building and carpentry. They're available in different lengths, diameters, head styles and finishes to suit a variety of timber applications.

When selecting wood screws, consider the thickness of the timber, the required fixing strength and whether the screw will be visible once installed.

Countersunk screws are often used where a flush finish is required, while other head styles may be more appropriate where a larger bearing surface or different appearance is needed.

Coach Screws vs Wood Screws

Coach screws are generally larger, heavy-duty fixings commonly used for suitable timber connections where substantial fastening is required. They typically have a hexagonal head designed for tightening with a spanner or socket.

Standard wood screws are available in a wider variety of sizes and head styles and are commonly used for general carpentry, joinery and timber assembly.

The correct choice depends on the materials, loads and connection requirements. For structural timber connections, follow the relevant design and manufacturer's fixing specifications.

Drywall Screws for Plasterboard

Drywall screws are designed for securing plasterboard to suitable framing systems. The correct screw depends on whether the board is being fixed to timber or metal studs, the thickness of the plasterboard and the framing specification.

Coarse-thread drywall screws are commonly used for suitable timber framing, while fine-thread drywall screws are often used with appropriate light-gauge metal studs. Always check the manufacturer's intended application.

Choose a screw length that provides the required penetration into the supporting framework without damaging concealed services or compromising the installation.

What Are Collated Screws Used For?

Collated screws are supplied in connected strips designed for use with compatible automatic-feed screwdrivers. They're particularly useful for repetitive fixing tasks such as plasterboarding and suitable flooring installations.

Using collated screws can reduce the time spent handling individual screws, making them a practical option for larger projects where many fixings are required.

Always check that the screw strip, screw type and dimensions are compatible with your tool and the material being fixed.

Choosing Screws for Brick, Block & Concrete

Masonry screws are designed for suitable fixing applications involving masonry materials such as brick, block and concrete.

Some masonry screws are designed to create a fixing directly within a correctly prepared hole, while other fixing systems use compatible plugs or anchors.

The correct fixing method depends on the masonry type, condition of the substrate and expected load. Always follow the manufacturer's drilling, installation and load requirements.

Which Screws Are Suitable for Outdoor Use?

For external projects such as fencing, decking and garden structures, corrosion resistance is an important consideration.

Different screw coatings and materials offer different levels of protection against moisture and corrosion. Zinc-plated screws may be suitable for certain sheltered applications, while external environments may require appropriately coated or stainless steel screws.

When fixing treated timber, check that the screw material and coating are compatible with the timber preservative and expected exposure conditions.

Understanding Screw Sizes

Screws are commonly described by their diameter and length. For example, a screw listed as 5.0 x 80mm generally has a nominal diameter of 5mm and a length of 80mm.

For many countersunk screws, length is measured from the top of the head to the tip, although measurement conventions vary with head style and product type.

Choosing the correct size involves considering the thickness of the materials being joined, the required penetration depth and the strength of the connection.

Need Advice Choosing Screws?

If you're unsure which screws are suitable for your project, visit your local County Building Supplies branch or contact our team. Tell us what you're fixing, the material you're fixing into and the size you require, and our team can help you find a suitable product from our range.