Mechanical Expansion Joint Cover Product Information & Optional Extras

Optional Extras

Tnemec PZ9 Protective Coating

Tnemec PZ9 is a coating applied to aluminium surfaces to be embedded in cement and should be considered to minimise corrosion and electrolytic reaction with embedded members.

Latham Australia recommends using Tnemec PZ9 for all embedded sections, especially those that are externally exposed and in areas where water or moisture are frequently present.

Specify “with Tnemec PZ9 Protective Coating”

Cutting to Length and Factory Assembly

All expansion joint ranges can be factory cut from full lengths to site-supplied measurements at extra cost.

On request, all recessed and surface-mounted expansion joint covers can be factory-assembled for quicker installation. Extra charges apply.

Specify “factory assembled”

Please Note: Some profiles require on-site assembly by design.

Water Gutter

Optional Water Gutter is available for most Latham expansion joint covers - look for the symbol in the technical data sheet “features” description.

The water barrier is included by default as part of the joint for all roof and roof-to-parapet expansion joint covers. Latham expansion joint water barriers are made of high-quality flexible PVC for the VWS Series and Neoprene for the BFG Series. Where possible, water barriers are supplied in continuous lengths to minimise field splicing.

While exterior wall covers effectively keep most water out of the joint, wind, blowing rain, and seepage require the use of water barriers at exterior joints. Water barriers are also recommended for interior floors that are subject to mopping and washing.

Specify “V” after the product code for the water barrier, eg CA-25V.

At exterior walls, water should drain freely to the exterior at the base of the joint cover. When difficult drain points occur in roof and floor joints, a flexible PVC drain tube may be installed, allowing drainage to the building’s drainage systems.

Mechanical Fixings

Lathams do not supply fixings. Suitable fixings should be sourced for your application, and ensure the expansion joint cover is securely fixed to the structural slab at the indicated centres on the relevant page of this publication for the joint cover selected.

All data sheets and drawings of the expansion joint covers indicate the fixing centres and the size of the pre-drilled holes. The size of the pre-drilled hole indicates the fixing diameter that Latham recommends for the particular expansion joint cover.

Seismic Movement

All of Latham’s expansion joint covers tolerate some amount of seismic movement, but the systems in our Seismic Movement Range are designed for large joint widths (as standard up to 600mm) and allow virtually +/-100% movement. Custom wider designs are available on request.

Powder Coating/Anodising

Both interior and exterior expansion joint covers in wall, ceiling, roof, and parapet applications can be successfully anodised or powder-coated to harmonise with the surrounding finish.

Antimicrobial Powder Coated Finish

Latham’s antimicrobial powder coat finish is a made-to-order surface treatment for aluminium expansion joint covers.

Treated using Interpon D1000 AM by AkzoNobel and applied by Platinum Approved Applicators, this finish utilises BioCote Silver ion technology to actively inhibit bacterial growth by up to 99.9%, validated to ISO 22196 Standards.

It's suitable for applications such as hospitals, cleanrooms, laboratories, food-safe environments, kitchens, and hygiene-focused infrastructure.

Latham’s antimicrobial powder coat is effective against a wide range of bacteria, including E. coli, MRSA, Salmonella and Listeria.

Antimicrobial powder coat is a finish available in a wide range of colours and can be used for floor, wall, and ceiling expansion joint covers.

Natural Wood Grain Metal Finish

The beauty of Australian Timbers inspires our Wood Grain Metal Finish and Latham is pleased to offer a range of multi-layered powder-coated surfaces for aluminium, with a natural looking textured wood grain finish.

The specialist treatment is available in a wide range of colours to work with natural timber for wall and ceiling expansion joint covers. Our Natural Timber Metal Finish can be applied to all exposed aluminium surfaces and is often used in conjunction with the Latham Wall-Line Series wall and ceiling expansion joint covers, allowing them to blend in with the surrounding finish while still performing as expected and required.

Contact your Latham representative for further information and to enquire about available colours.

Both interior and exterior expansion joint covers in wall, ceiling, roof, and parapet applications can be successfully anodised or powder coated to harmonise with the surrounding finish.

Latham Australia does not recommend the Natural Timber Metal Finish, Powder Coating or Anodising for floor, or floor-to-wall, expansion joint covers, as the surfaces may be scratched and scuffed by foot traffic and cleaning appliances, etc. All expansion joint ranges can be factory cut from full lengths to site-supplied measurements at extra cost.

Tnemec PZ9 Protective Coating

A coating applied to aluminium surfaces that are to be embedded in cement. Tnemec PZ9 protective coating should be considered to minimise corrosion and electrolytic reaction with embedded members. Latham Australia recommend the use of Tnemec PZ9 for all embedded sections, particularly externally and in areas where water or moisture is common. Specify “with Tnemec PZ9 Protective Coating”

Slip-Resistant Coatings

Latham offers two types of slip-resistant coating for floor expansion joint cover plates. These are particularly relevant when maintaining slip resistance is required for the entire floor. Even when this isn’t a major consideration, Latham recommends that a slip-resistant coating be considered for all cover plates 100mm and wider.

Flex-Tred is the heaviest duty slip‑resistant coating available and offers a P5 slip rating. When factory applied, this provides the most durable coating available and is often used in heavy pedestrian applications, such as railway stations, schools, factories, warehouses and similar sites.

Sumo Grip provides a virtually invisible cover with a P4 slip rating once treated, which can be applied to any metal floor expansion joint cover.

Both systems are resurfaceable, so if they are subjected to very substantial traffic over a long period or are damaged by other types of traffic, the surface coating can be freshly re-applied on-site.

Key Aspects of the slip rating

Based on AS 4586-2013 Standard - Slip resistance classification of new pedestrian surface materials. According to the standard a product with a rating of P4 has a high slip resistance, its suited to external paving, pool surrounds, walkways and uncovered ramps, external colonnade, walkways and pedestrian crossings. A product with a rating of P5 has a very high slip resistance and is the highest rate achievable. It is suitable for loading docks, external ramps and sloping driveways, applications where the greatest slip resistance is required.

Option 1: Flex-Tred

Latham Flex-Tred is a heavy-duty, non-slip, wear‑resistant factory-applied tape with an independently tested non-slip rating of P5 as detailed in AS 4586-2013.

The tape is factory applied, meaning the plate is cleaned and prepared. The Flex-tred is then pressure applied and heat cured, ensuring the best possible bond.

As standard, Flex-Tred is supplied in Sparkling Black colour but is also available in Grey and Brown in widths up to 600mm. Other colours are available up to 300mm wide. Contact your representative or see the Latham website for the full range.

Flex-Tred is compatible with smooth stainless steel, brass, and aluminium cover plates; however, it is not suitable for ribbed aluminium or ribbed brass plates, for which Latham Sumo Grip should be considered.

Specify “with Latham Flex-Tred Coating” when specifying the expansion joint cover.

Option 2: Sumo Grip

Latham Sumo Grip is a heavy-duty, anti-slip, and wear-resistant factory-applied coating, boasting an independently tested anti-slip rating of P4 as detailed in AS 4586-2013. The Sumo Grip is factory applied, meaning the plate is cleaned and prepared prior to application and heat cured to ensure the best bond possible. Once applied, Sumo Grip is virtually invisible.

Latham Sumo Grip is available for all standard Latham floor joints with metal cover plates.

Specify “with Latham Sumo Grip resurfaceable slip-resistant coating”.

Factory Curvable

Many of Latham’s range of Mechanical Expansion Joint Covers can be supplied curved from the factory, or a custom design can be manufactured to suit the requirements.

Contact your Latham representative to discuss the specific needs of your application.

Anti-Tamper Machine Screws for Tie Bars

Lathams recognise that, in certain applications, Anti-Tamper fixings are a worthwhile consideration. With the current high cost of metals worldwide, there is a strong market for scrap metal, and some unscrupulous entrepreneurs might see removing cover plates for scrap as a legitimate opportunity.

Other uses for Anti-Tamper fixings could include institutional settings, where removing a cover or component might pose a security risk. In such cases, Lathams can supply Anti-Tamper Stainless Steel Screws, which feature custom heads that can only be tightened or loosened with Latham-supplied drivers.

Anti-tamper stainless steel screws and drivers are available for all Expansion Joint Covers fitted with Spring Steel Tie Bars.

Specify “Supplied with Anti-Tamper Screws and Custom Drivers".

8-Gauge Countersunk Head Stainless Steel Anti-Tamper Screws with Custom Drivers can be supplied when choosing certain Surface-Line Expansion Joint Covers (BS, BSL, ABS and ABSL Series) and Light-Duty (FDR, FDRW, FCSR, FCWSR, FTSR, FTWSR, FTVR, FTWVR, WR and WCR Series), and by selecting “Factory Drilling”.

Specify “Factory Drilling with 8-Gauge Countersunk Head Stainless Steel Anti-Tamper Screws with Custom Drivers”.

With ¼” and 5⁄16” Anti-Tamper Stainless Steel Screws, one custom driver will be supplied for every 100 screws needed. For 8-gauge countersunk head stainless steel screws, one custom driver will be supplied per 250 screws required. For further information, contact your Latham Australia representative.

Finishes

Coatings

Titazel PE31 is a protective coating applied to all steel members to protect and control electrolytic action.

A clear anodised 20-micron finish is standard for all wall and ceiling visually exposed cover units, except for the M, ML, MSM, MLSM and WR Series, which are supplied with mill finish, unless otherwise specified.

Protective Tape (Anodised Finishes)

All exposed anodised aluminium surfaces will be supplied and covered with protective tape/film.

All 2B-finish stainless steel cover plates, except those with Latham abrasive slip-resistant coatings will be supplied with protective tape.

Materials covered with protective tape should not be subjected to prolonged sunlight or extreme temperatures. The tape should be removed during installation or within 30 days of delivery.

Protection of Visible Faces

Latham can apply a protective tape to the visible faces of expansion joints, regardless of the finish, to maintain their appearance during transit and installation, which can be quite a messy process. The tape is similar to a thin masking tape and should be removed. This is an optional extra that incurs an additional charge.

Specify “with protective tape coating”

Components

Anchors

Most Latham Flexible Mechanical Expansion Joint Covers are supplied with pre-drilled holes in the side extrusions for fixing. Some systems carry removable/adjustable anchors with brass extrusions featuring predetermined locations.

In standard applications, CA-16 aluminium/BM-16 brass block-out or CA-6 aluminium/BS-6 brass cast-in type anchors are installed at approximately 500mm centres on both sides of the embedded members.

CA-16 aluminium or BM-16 brass block-out anchors will be supplied unless otherwise specified. T

To specify CA-6 aluminium or BS-6 brass cast-in anchors for suitable ranges, specify “Latham Mechanical Expansion Joint Cover Type…… with CA-6 or BS-6 cast-in anchors”

Fixing Holes and Locations

Most Latham Flexible Mechanical Expansion Joint Covers are supplied with pre-drilled holes in the side extrusions for fixing.

Most expansion joint covers are supplied with side members pre-drilled to suit fixing sizes indicated. Consult the relevant joint series page found in this publication. If, at the time of installation, hole locations are unsuitable, they can be re-drilled on-site at a nearby location.

Latham expansion joint series with CA-6 and CA-16 anchors pictured above, should be located at approximately 500mm centres, there should be 7 per length of side, and spaced not further than 75mm from either of the ends.

Factory Fabrications

Factory Fabrication of Junction Components

Latham Australia recommends that all corners, crossovers, and tees used in floor applications be factory fabricated rather than assembled on-site. Factory fabrication provides greater accuracy in alignment and joint integrity, ensuring the system performs consistently under expected load and movement conditions. This approach reduces the risk of installation error and maintains the intended aesthetic and structural design.

When these components are fabricated in the factory, mitres and cover plates are fully welded and precisely ground to produce virtually invisible joints. This level of finish is difficult to replicate in the field and contributes to a more seamless visual result. The controlled environment of the factory also allows for stricter quality assurance, ensuring each unit meets performance and durability standards.

Tie Bars (Centring Bars)

Latham manufactures a range of different Tie Bars (also known as centring bars) for our Mechanical Expansion Joint Covers

All tie bars are made from specially sourced spring steel, which is cut to the required length before being edge bevelled and having holes drilled and tapped as necessary, prior to the steel being finally hardened and the bar treated with Titazel PE-22 powder coating and Titazel PE-20 zinc coating. The coating helps protect the tie bar from moisture, particularly in external applications.

Latham tie bars are generally located at a maximum of 500mm centres, depending on the length of the extrusions and therefore the cover plate length. Cover plates and extrusions range from 2400mm to 4000mm, depending on the actual series and system selected.

On request, Latham can increase the number of tie bars in a length. This often assists with impact loads in heavy traffic areas where excessive vehicular traffic is expected, or where forklift or pallet truck traffic is anticipated.

TB1

This is Latham’s most common tie bar and is available in lengths from 100mm to well over 1000mm. The nylon spheres (16mm) that are permanently attached to the end of the tie bars minimise wear on the aluminium extrusions.

TB2

This is a heavy-duty version of TB1. It carries a larger nylon sphere (21mm), and the steel bar is wider at 25mm. TB2 is available in a range of lengths from 150mm to suit the joint width and movement requirement. Again, the nylon balls are permanently attached to the end of the tie bars to minimise wear on the aluminium extrusions. 

PTB1

The regular pin-style tie bar is used throughout Latham’s Surface Mounted range and Wall-Line range of expansion joint covers which allow for a minimum profile depth while still offering the heavy duty construction of a Latham tie bar. PTB1 is available in a range of lengths from 150mm to suit the joint width and movement requirement.

CUSTOM TIE BARS

From time to time Latham will work with architects, engineers, and clients to meet unusual movement needs, and this may require custom-designed expansion joint covers and custom-designed tie bars.

PTB2

The heavy-duty pin-style tie bar is used throughout Latham’s Extra Heavy Duty expansion joint cover ranges. PTB2 is available in a range of lengths from 150mm to suit the joint width and movement requirement.

TB1A

The turned-up style tie bar, which is manufactured as seen, or sometimes is manufactured as a standard style tie bar with a large upturned pin in one end to replicate the fold. These tie bars are generally used in Latham’s larger seismic ranges of roof-to-parapet expansion joint covers. These ensure the covers remain tight and aren’t affected by the wind. The fixing hole for the tie bar is off centre to allow for the seismic movement. TB1A is available in a range of lengths from 150mm to suit the joint width and movement requirement.

PTBA

The turned-up style tie bar, which is manufactured as seen, or sometimes is manufactured as a standard style tie bar with a large upturned pin in one end to replicate the fold. These tie bars are generally used in Latham’s larger seismic angle wall expansion joint covers. These ensure the covers remain tight and aren’t affected by the wind. The fixing hole for the tie bar is off centre to allow for the seismic movement. PTBA is available in a range of lengths from 150mm to suit the joint width and movement requirement.

PLTB

The extra-long height of the pin bars is designed exclusively for use with Latham’s IWSM Series Seismic wall and ceiling expansion joint covers. The longer pins bring into play the seismic ramps in the expansion joint cover during seismic activity. The PLTB tie bar is available in a range of widths from 300mm.

PLTBA

The extra-long height of the pin bars and folded grab handles are designed exclusively for use with Latham’s IWLSM Series Seismic wall and ceiling expansion joint covers. The longer pins bring into play the seismic ramps in the expansion joint cover during seismic activity. The PLTBA tie bar is available in a range of widths from 300mm.