Builders Metalwork Buying Guide: Joist Hangers, Straps & Brackets

Builders metalwork covers a wide range of structural and general-purpose steel components used to connect timber, restrain walls, reinforce joints and complete construction details. Joist hangers, restraint straps, angle brackets and braces can look simple, but choosing the wrong size or type can compromise the connection they are meant to create.

This builders metalwork buying guide explains the main product groups found in our range, what each is generally used for and the details to check before ordering. Browse the full metalworks collection as you read so you can compare the relevant sizes and formats.

What is builders metalwork?

Builders metalwork is the collective term for fabricated metal connectors and support components used in timber and masonry construction. Products can be designed to transfer loads, provide restraint or simply reinforce a joint. Common examples include joist hangers, restraint straps, angle brackets, wall ties and plates.

Many structural metalwork products are safety-critical. The correct connector depends on the loads, supporting materials, timber dimensions, fixing pattern and installation detail. Where a product forms part of a structural design, follow the engineer's specification and the manufacturer's declared capacities.

Joist hangers

Joist hangers support the end of a joist or beam where it meets another structural member. They are widely used in floors, roofs and timber framing, but different hanger types are designed for different supporting materials.

A timber-to-timber hanger is not automatically suitable for masonry, and a masonry hanger may need a specific embedment or course arrangement. Check joist width, depth and the supporting construction before buying. The hanger should fit the timber correctly without excessive gaps or forced bending.

Timber-to-masonry joist hangers

Where timber joists meet masonry, a product such as a timber-to-masonry joist hanger may be specified. These hangers are designed differently from connectors fixed only to timber.

Installation details are critical. Masonry strength, bearing, embedment and mortar all influence performance. Do not trim, drill or modify structural connectors unless the manufacturer specifically permits it.

Restraint straps

Restraint straps are used in a range of wall and roof details to connect elements and provide lateral restraint. Straight straps and bent straps serve different layouts, so the shape and length should match the detail shown on the drawing.

Our range also includes bent restraint straps with a 100mm leg. A pre-bent strap can simplify certain junctions, but the bend location must suit the construction. Check strap length, width, thickness and fixing requirements rather than ordering on length alone.

Angle brackets

Heavy duty angle brackets are used to reinforce right-angle connections in timber and other compatible construction details. They are available in different dimensions because the loads and member sizes vary from one application to another.

For lighter general-purpose work, corner braces may be more appropriate. Our BZP corner braces are supplied in packs and can be useful for non-structural or lighter-duty joints where the selected size and fixing arrangement are suitable.

What does BZP mean?

BZP commonly refers to bright zinc plated steel. The zinc coating provides a degree of corrosion protection, but the correct finish still depends on the environment. Exterior, coastal or highly corrosive locations can require a different coating or stainless-steel product.

Do not assume every zinc-plated bracket is suitable outdoors. Check the manufacturer's stated service environment, especially where connectors may remain damp or be exposed to treated timber chemicals.

Choosing the right connector size

Connector dimensions should match the timber and structural detail. A hanger that is too narrow can damage the joist or prevent correct seating; one that is too wide can leave gaps and reduce the intended contact. Brackets and straps also need enough length and fixing positions to transfer the required load.

Read product dimensions carefully and compare them with the drawing before ordering. If several similar sizes are listed under one product, check the exact variant rather than assuming the first option will fit.

Fixings for builders metalwork

The connector and its fixings work as a system. Nails, screws or bolts need the correct diameter, length, head type and material. Using ordinary wood screws where the manufacturer specifies structural nails or connector screws can reduce the capacity of the joint.

Fill the required fixing holes and follow the pattern stated in the product guidance. More fixings are not always better if they are the wrong type or placed incorrectly. For engineered connections, use only approved fixings.

Corrosion and external use

Metalwork used outdoors or in damp construction can be exposed to corrosion. Galvanised, zinc-plated and stainless-steel finishes offer different levels of protection. The correct choice depends on exposure, expected service life and contact with other materials.

Treated timber can be more corrosive to some metals, especially in damp environments. Check connector compatibility with the timber treatment and use the coating grade required by the manufacturer or project specification.

Metal sheeting and perforated steel

The metalworks range also includes products beyond structural connectors. Perforated steel sheet can be used for fabrication, screening, guards and workshop projects where an open pattern is required.

Raw steel behaves differently from coated structural connectors and can rust if left unprotected in damp conditions. If the finished project requires corrosion resistance or a decorative finish, allow for suitable preparation and coating.

When should you use structural calculations?

Any connection carrying significant structural loads should be designed or selected using published load data. Floor joists, roof members, wall restraint and load-bearing timber frames are not areas for guesswork. The connector manufacturer normally publishes capacities based on specific fasteners and substrates.

If the drawing names a particular hanger, strap or bracket, do not substitute a visually similar product without checking the design capacity. Small changes in thickness, steel grade, hole pattern or geometry can alter performance.

How to order builders metalwork efficiently

Group connectors by type, size and location before ordering. A floor may require several hanger sizes, while roof and wall details need straps and brackets. Counting directly from drawings reduces the risk of missing a connector that then delays the carpentry work.

Check whether items are sold individually or in packs. A low unit price can be misleading if a product is supplied only as a pack of 100, while a project may need only a small quantity. Conversely, pack quantities can offer better value on larger developments.

Wall ties and masonry connectors

Builders metalwork also includes wall ties and masonry connectors used to link leaves of cavity walls or connect new masonry to existing construction. The correct tie depends on cavity width, substrate, exposure and the wall design. Length is especially important because the tie must achieve the required embedment on both sides while maintaining the designed cavity.

Do not replace a specified stainless-steel tie with a cheaper plated product simply because the dimensions look similar. Material grade, corrosion resistance and declared performance are part of the specification.

Plates, braces and repair work

Flat plates and braces can be useful for strengthening general timber joints, repairing non-structural assemblies and fabricating workshop projects. Where the joint is structural, however, the load path should still be checked. A plate with more holes is not automatically stronger if the steel thickness, fasteners or edge distances are unsuitable.

For refurbishment work, inspect the timber or masonry first. New metalwork cannot compensate for rotten timber, loose masonry or an inadequate supporting member. Repair the substrate before adding connectors.

Comparing metalwork pack prices

Builders metalwork is frequently sold in packs, particularly smaller brackets and braces. Compare cost per connector as well as total pack price. On large projects, packs can be economical; on a one-off repair, buying a 100-pack can create unnecessary surplus. Keep spare structural connectors labelled so their type and size are not confused later.

Builders metalwork buying checklist

• Identify whether the connection is timber-to-timber, timber-to-masonry or another substrate.
• Check joist, beam or member dimensions.
• Use the specified hanger, strap or bracket type.
• Confirm connector coating for the environment.
• Buy the exact approved nails, screws or bolts.
• Check pack quantity before comparing price.
• Do not cut or alter structural connectors without approval.
• Use published load tables for structural work.
• Store metalwork dry and protected before installation.

Frequently asked questions

What size joist hanger do I need?

The hanger should suit the joist dimensions and structural load. Measure the joist width and depth and check the manufacturer’s compatible size and load data.

Can I use screws in joist hangers?

Only use screws specifically approved for the hanger system if the manufacturer allows them. Ordinary wood screws are not a substitute for structural connector fixings.

What are restraint straps used for?

They connect and restrain building elements such as walls, floors and roofs in specified details. Straight and bent straps are used in different arrangements.

Are zinc-plated brackets suitable outside?

Not necessarily. External and corrosive environments can require heavier galvanising or stainless steel. Check the service class and coating requirement for the project.

Shop builders metalwork online

JJ Building Materials supplies builders metalwork including joist hangers, restraint straps, angle brackets, braces and metal sheet products. Match every connector to the supporting material, dimensions and load requirements, and order the correct fixings at the same time.