Fire-Resistant Joint Sealing Solutions

A fire-resistant joint depends on more than filling the visible gap. Sika passive fire protection products in this Industrial Shed collection include Sika® Backer Rod Fire & Sika Boom®-420 Fire, giving professional installers purpose-built options for fire stopping, fire-resistant joint sealing & suitable linear seal applications.

Different openings call for different fire protection materials. Sika Backer Rod Fire provides compressible mineral-wool backing for suitable fire-resistant joints, while Sika Boom-420 Fire is a self-expanding polyurethane foam developed for specified interior linear seals.

Correct selection starts with the complete joint rather than the product label. Wall or floor construction, joint dimensions, backing depth, adjoining materials & the tested configuration can all influence the required fire performance.

► Passive fire protection
► Fire-resistant joint sealing
► Linear fire seals
► Horizontal & vertical building joints
► Mineral-wool fire backing rod
► Fire-resistant expanding foam
► Wall & floor applications
► Professional fire-stopping installations

What Is Sika Passive Fire Protection?

Passive fire protection forms part of the building rather than relying on somebody to activate it. Correctly specified fire-stopping systems help maintain fire resistance where joints, gaps or other openings interrupt fire-resisting construction.

Linear joints are particularly important because they can extend across significant sections of a wall or floor. Suitable fire-resistant sealing materials help address these openings when installed as part of the required system.

Every component has a defined role. Fire backing material can establish the required joint profile, while compatible sealants, foams or other specified products complete the arrangement according to the tested design.

Sika Fire Protection Products in This Collection

Sika Backer Rod Fire

A backing rod can do far more than simply occupy space behind a sealant. Sika Backer Rod Fire is a circular, compressible mineral-wool backing material wrapped with glass-fibre yarn for use in suitable fire-resistant horizontal & vertical joints.

Flexible construction helps the rod accommodate permitted variations in joint width & alignment. Once correctly selected, it provides backing within the fire-resistant joint arrangement & helps establish the required sealant profile.

Industrial Shed carries Sika Backer Rod Fire across multiple diameters:

► 12 mm
► 15 mm
► 20 mm
► 40 mm
► 50 mm
► 60 mm

Accurate sizing matters before installation begins. Match the fire backing rod diameter to the measured joint width & specified system rather than choosing the largest size that can physically be compressed into the opening.

Sika Boom-420 Fire

Some linear gaps are better suited to an expanding fire-resistant foam than a mineral-wool backing rod. Sika Boom-420 Fire is a one-part self-expanding polyurethane foam developed for suitable interior linear seals in walls & floors.

Application flexibility can make difficult spaces easier to access. Its combi-valve supports gun or nozzle application, while cured foam can be cut, trimmed & sanded where the installation requires finishing.

Fire performance always belongs to the tested arrangement. Sika documents fire resistance of up to 180 minutes according to AS 1530.4:2014, depending on the applicable configuration.

Why Choose Sika Fire-Stopping Products?

Reliable fire-stopping work starts with materials developed for clearly defined applications. Sika's passive fire products are supported by technical information that helps installers match products with suitable joint types, dimensions & construction details.

Choice becomes easier once the function inside the opening is understood. Sika Backer Rod Fire provides fire-resistant backing for suitable joints, while Sika Boom-420 Fire expands to fill specified interior linear seals.

Australian construction projects can demand documented fire performance rather than assumptions based on product appearance. Relevant Sika systems are supported by fire-testing information, but the required rating still depends on the complete installation matching the applicable configuration.

Practical handling matters once work reaches site. Compressible fire backing rod can accommodate permitted joint irregularities, while one-part fire-resistant PU foam offers convenient gun or nozzle application for suitable gaps.

Common Applications

Fire-Resistant Linear Joints

A long joint through fire-resisting construction can become an important part of the compartmentation strategy. Suitable Sika fire-stopping materials can form part of specified linear seal systems across compatible walls & floors.

Joint dimensions determine more than material quantity. Width, depth, backing position & the adjoining construction should all correspond with the applicable fire-resistant joint detail.

Wall Joints

Vertical openings put retention, alignment & joint depth into sharp focus. Sika Backer Rod Fire can provide compressible mineral-wool backing within suitable vertical fire-resistant joint systems.

Finished dimensions can differ from what appears on the drawing. Measure the actual opening before choosing a rod diameter & confirm the required installation depth against the specified configuration.

Floor Joints

Horizontal placement may be easier to access, but fire-resistance requirements remain just as important. Sika Backer Rod Fire can also form part of suitable fire-resistant floor joint arrangements.

Consistent installation helps the complete seal match its intended profile. Check joint width at multiple points where construction tolerances create variation across longer openings.

Interior Linear Gaps

Irregular gaps can make conventional joint materials difficult to position. Sika Boom-420 Fire provides an expanding fire-resistant PU foam option for suitable interior linear seals.

Expansion doesn't make fire foam universal. Confirm the supporting wall or floor construction, gap dimensions & required fire performance before application.

Commercial & Industrial Buildings

Warehouses, workshops, commercial buildings & industrial facilities can contain numerous joints through fire-resisting construction. Correctly specified passive fire protection helps maintain the intended performance of these building elements where linear openings occur.

Project documentation should lead product selection. Work from the approved detail, relevant fire assessment & current manufacturer information rather than choosing a fire-stopping material solely from its name or advertised maximum rating.

Sika Fire Protection Product Selection Guide

Identify the Opening

Is the job actually a linear joint? Establishing the opening type first helps prevent a joint-sealing product from being incorrectly selected for another fire-stopping application.

Check:

► Wall or floor construction
► Linear joint or gap type
► Joint width
► Joint depth
► Required fire resistance
► Interior or exterior exposure
► Movement requirements where applicable
► Required backing material
► Compatible finishing products where specified

Clear dimensions make the next decision much easier. Once the opening is understood, match the Sika fire protection product to the documented system.

Choose Fire Backer Rod or Expanding Foam

These products solve different problems inside the joint.

The difference is practical. Fire backer rod establishes backing within an appropriate joint system, while fire-resistant expanding foam fills suitable linear gaps according to its documented configuration.

Measure Backer Rod Size Carefully

Nominal joint dimensions don't always survive the realities of construction. Measure the opening at several points before deciding which Sika Backer Rod Fire diameter is appropriate.

Compression needs to remain within the permitted system requirements. Oversizing or undersizing the rod can alter the joint profile, so follow Sika's applicable dimensional guidance rather than relying on visual judgement.

Check Interior or Exterior Exposure

Exposure can eliminate an otherwise suitable product immediately. Sika Boom-420 Fire is intended for interior applications.

Backing rod suitability depends on the complete joint system around it. Where a joint is externally exposed, check the accompanying sealant, supporting construction & complete specified configuration.

Verify the Required Fire Performance

The highest number on a product data sheet isn't automatically the rating of your joint. Fire resistance depends on construction type, dimensions, materials & the complete tested arrangement.

Sika Boom-420 Fire can achieve fire resistance up to 180 minutes in applicable configurations. Treat that figure as a system-dependent maximum rather than a blanket rating for every wall, floor or gap.

Prepare the Joint

Good fire-stopping materials still need a suitable opening to work within. Inspect the installation area before inserting backing rod or applying foam.

Look for:

► Dust
► Loose material
► Oil & grease
► Weak edges
► Incorrect dimensions
► Obstructions
► Existing incompatible materials
► Unsuitable moisture conditions

Preparation should follow the selected Sika product requirements. Remove materials that could interfere with installation & confirm the opening remains within the specified configuration.

Avoid Unverified Product Substitution

Two fire-resistant products can look similar without being interchangeable. Tested passive fire systems depend on specific materials, dimensions, supporting construction & installation arrangements.

Substitution deserves verification rather than guesswork. Where project documentation identifies a particular Sika fire-stopping system, confirm any proposed change before installation.

Sika Backer Rod Fire vs Sika Boom-420 Fire

Not sure which product family belongs in the opening? Focus on what the material needs to do.

One distinction deserves particular attention. A fire-resistant linear joint isn't automatically the same application as a pipe, cable or mixed-service penetration.

Expert Tips for Fire-Resistant Joint Sealing

Read the System Detail Before Ordering

Five minutes with the specified detail can prevent an expensive product mismatch. Confirm opening type, dimensions, fire-performance requirements & required components before calculating quantities.

Measure the Real Joint

Construction tolerances can turn one nominal width into several actual widths across the same project. Take measurements at multiple points so fire backing rod selection reflects the finished opening.

Don't Select by Maximum Rating Alone

A bigger fire-resistance number doesn't make a product more appropriate for the joint. Match the required performance to a tested configuration that reflects the actual construction.

Treat Fire Backer Rod as a Functional Component

Backing material isn't simply packing hidden behind the visible seal. Rod diameter, compression, position & compatibility can influence the completed fire-resistant joint arrangement.

Respect Interior-Use Limitations

Convenient application shouldn't override environmental suitability. Sika Boom-420 Fire is intended for interior use, so don't extend it into exposed exterior applications without appropriate documentation.

Protect Fire Foam From Permanent UV Exposure

A cured foam surface may look finished while still requiring protection. Sika Boom-420 Fire isn't permanently UV stable, making correct placement within the specified construction important.

Record Installed Fire-Stopping Products

Future inspections become easier when today's installation remains traceable. Where project procedures require documentation, record the product, location, system detail & relevant installation information.