VicRoads BTN 033 Update: Terra Firma Composite Pit Lids and Access Covers Listed Under Revised Standard

Victorian councils, road authorities, and contractors delivering major road and drainage projects can now specify Terra Firma composite pit lids and access covers directly, with their long-standing approval now reconfirmed under the updated BTN 033 – Structural Requirements for Reinforced Concrete Drainage Pits.

Traditional materials used for pit lids and access covers, like concrete and cast iron, have been falling out of favour due to concerns about durability, handling safety, and high maintenance demands – with many project managers, engineers, and contractors turning to Fibre-Reinforced Polymer (FRP) as an alternative.

The updated BTN 033 reinforces Terra Firma’s ongoing role in supporting the broader adoption of FRP technologies in Australian infrastructure.

What the updated BTN 033 means for Victorian projects

VicRoads has reinstated its detailed and thorough product approval process to ensure consistent quality and performance across the state’s public road network. BTN 033 compliance outlines the structural, load, and safety standards required for pit lids and access covers used in road and drainage infrastructure, ensuring they are suitable for different traffic and site conditions.

Terra Firma’s BTN 033-listed pit lids and access covers are designed, certified, and manufactured to meet the highest quality standards (BTN033 and AS3996). These three products are now available for specification and purchase under the updated framework:

• C150 to suit clear opening 1000×750 Class C
• D240 to suit clear opening 900×600 Class D
• D400 to suit clear opening 600 & 760 round Class D

Terra Firma is also the only manufacturer offering a composite D-Class access cover listed in the updated standard, enabling project teams to use lightweight, durable FRP solutions for heavy-duty applications, without the approval delays.

The benefits for Victorian projects

The updated BTN 033 framework supports faster, safer, and more efficient delivery of Victorian road and drainage infrastructure. With Terra Firma’s listing under the updated framework, these products can now be specified without additional testing, assessment, or administrative steps – removing quality risks, project suitability errors, and reducing approval delays and procurement barriers.

These pit lids and access covers are designed to meet the load class requirements outlined in BTN 033 Section 10 and Appendix B, ensuring suitability for different traffic and site conditions.

For engineers, designers, and contractors, this provides:

• Automatic eligibility for VicRoads and Victoria’s Department of Transport and Planning projects
• Reduced administrative overhead, with no additional approval stages required
• Fully compliant, meeting BTN 033 and AS 3996:2019
• Lower risk of incorrect product selection, particularly for D-Class applications

This allows project teams to move forward with composite solutions that meet the updated standard and are engineered for modern road conditions.

M80 Ring Road Upgrade: A longstanding partnership with VicRoads

Terra Firma has been at the forefront of the composite movement for years, working closely with VicRoads since 2010 to validate composite technologies for road infrastructure.

This partnership began during the M80 Ring Road Upgrade, where Terra Firma introduced FRP lids into a demanding, high-traffic environment to assess long-term suitability – subsequently demonstrating their durability, cost efficiency, and safety.

Over this period, Terra Firma has worked closely with VicRoads and Composites Australia to ensure composite technologies were understood, tested, and incorporated into relevant standards and technical requirements.

This long-term collaboration has helped pave the way for FRP products in getting recognised as a practical, compliant alternative to traditional materials.

Terra Firma’s commitment to quality, safety, and innovation in infrastructure solutions and collaborations led to the successful inclusion of composites in Australian standards and BTN 033 structural requirements.

Case study: M80 Ring Road Upgrade

On the M80, composite pit lids were trialled to address ongoing issues with concrete covers, including breakages, handling risks, and frequent maintenance requirements. Terra Firma’s FRP pit lids demonstrated clear advantages:

• Safer handling: Lightweight construction reduces the risk of manual handling for crews working in high-traffic areas.
• Long-term durability: Stable performance under heavy vehicle loading and continuous traffic.
• Faster access: Simple lifting mechanisms enable quicker inspection and maintenance tasks.
• Low maintenance requirements: Materials that resist corrosion and deterioration over time.
• Whole-of-life costs: The single unit cost for maintenance of concrete is about 2.5 times more expensive than Terra Firma’s FRP lids. FRP lids reduced installation and maintenance costs, saving VicRoads $500,000.

The success of the M80 trial helped build confidence in composite solutions and contributed to their consideration in later standards and VicRoads specifications. And the original C Class lids included in the Ring Road upgrade are still performing.

Designed for modern infrastructure needs: Whole-of-life benefits of FRP

Terra Firma’s composite pit lids and access covers are engineered to support long-term safety, reliability, and efficiency. FRP construction offers several advantages over concrete, steel, and cast iron alternatives:

• Safety and OH&S: Lightweight design reduces lifting risk and meets harmonised Work Health and Safety (WHS) standards by providing safer handling during installation and maintenance. This makes FRP a great option for designers regarding their OH&S obligations
• Ease of installation: No heavy machinery required, with single-person removal and installation possible
• Corrosion resistance: Non-corrosive materials eliminate rust and chemical degradation
• Electrical safety: Non-conductive material eliminates stray voltage hazards
• Transparent to radio waves: FRP doesn’t interfere with wireless monitoring or communication systems, removing the need to lift the covers
• Whole-of-life savings: Reduced maintenance and fewer replacements over time
• Longevity: Stable long-term performance with a service life exceeding 20 years
• Superior structural integrity: Terra Firma pit lids retain their structural integrity even when damaged. Unlike concrete, they won’t break apart and fall into the pit
• Sustainable: Manufactured from materials that do not require hazardous coatings or preservatives.

These benefits help reduce operational risk, improve safety outcomes, and support more efficient maintenance planning.

Leading the way in composite access solutions

This update reinforces Terra Firma’s commitment to delivering safe, durable, and compliant access solutions for both public and private infrastructure projects.

As the only supplier offering a composite D-Class access cover listed in the updated standard, Terra Firma continues to support councils, designers, and contractors with products engineered for long service life and reliable performance.

Working on a VicRoads or DTP job? You can get started right away with Terra Firma. Contact us today for expert guidance tailored to your project’s unique requirements.