Advanced Slab Edge Termite Management for Steel Frame Kit Homes in Australia

Advanced Slab Edge Termite Management for Steel Frame Kit Homes in Australia

Introduction

For the Australian owner-builder embarking on the construction of a steel frame kit home, understanding and implementing robust termite management systems, particularly at the critical slab edge interface, is not merely a regulatory obligation but a cornerstone of long-term structural integrity and peace of mind. While steel frames themselves are impervious to termite attack, the comprehensive building system, including timber components (e.g., roof trusses, internal fit-out, timber flooring, door frames) and critical service penetrations, remains highly vulnerable. Furthermore, the National Construction Code (NCC) and various state-specific regulations mandate proactive prevention, recognising the economic devastation termites can inflict. This advanced guide delves into the intricate details of slab edge termite protection, offering a rigorous, technical, and practical resource tailored specifically for the discerning owner-builder engaged in steel frame construction. We will explore the regulatory landscape, advanced design considerations, material specifications, and installation methodologies to ensure full compliance and superior protection.

This guide is designed for the advanced owner-builder – one with a solid understanding of construction principles, regulatory frameworks, and a readiness to engage with complex specifications and engineering considerations. We will move beyond superficial explanations, providing in-depth analyses of compliant solutions, cost implications, and strategies for meticulous execution. The objective is to equip you with the knowledge to not only select and install an effective termite management system but also to confidently interpret engineering drawings, liaise with pest management professionals (PMPs), and ensure your steel frame kit home benefits from best-in-class protection against these relentless pests.

Understanding the Basics: Termites, Steel Frames, and Vulnerabilities

Australia is home to over 350 species of termites, with around 30 being significant pests that can inflict severe damage to timber and other cellulose-based materials within a building structure. Subterranean termites, such as Coptotermes acinaciformis, Mastotermes darwiniensis, and Schedorhinotermes species, are the most destructive. They build extensive underground tunnel systems (mudding) to protect themselves from predators and dehydration, using these tunnels to access food sources, often undetected, for extended periods. Their presence within a building can compromise structural elements, diminish property value, and necessitate expensive remediation.

While the primary structural components of your kit home – walls, roof trusses, and subfloor framing made from galvanised steel like TRUECORE® and other BlueScope Steel products – are inherently immune to termite attack, it is a fallacy to assume a 'termite-proof' building. The vulnerability shifts to:

1. Timber elements: Any timber used, including sarking, roof battens (if not steel), internal timber framing (e.g., for non-load-bearing partitions, if not steel), window/door frames, skirtings, architraves, floor coverings (e.g., hardwood floors, particleboard), kitchen cabinetry, and timber decking attached to the building.
2. Service penetrations: These include plumbing pipes (water, waste), electrical conduits, data cables, and HVAC ducts entering the building through the slab. These provide direct concealed pathways for termites from the soil to the building interior.
3. Concealed access points: Termites are adept at finding minute gaps (as small as 0.8 mm) between the slab edge and external cladding, or through cracks in the slab itself, to gain concealed entry. The goal of slab edge protection is to force termites into the open, making their presence detectable.

For steel frame kit homes, the long-term durability of the galvanised steel (e.g., Z275 coating for TRUECORE®) ensures corrosion resistance and inherent protection from insect attack. However, this does not absolve the owner-builder from meeting stringent termite management regulations. The NCC and AS 3660 series of standards are designed to protect the entire building system, regardless of the primary structural material. Any part of the building that could allow concealed termite entry or contains susceptible materials must be protected.

Australian Regulatory Framework

The Australian regulatory landscape for termite management is primarily governed by the National Construction Code (NCC) 2022, specifically Volume Two (Building Code of Australia - BCA Class 1 and 10a Buildings), complemented by a suite of Australian Standards. These regulations are periodically updated, and it is imperative that owner-builders consult the most current editions.

NCC 2022 Provisions

The key performance requirement for termite management is H1V5 Termite Risk Management (NCC 2022, Volume Two, Performance Solution H1V5, or through the Deemed-to-Satisfy (DtS) Provisions H4P1). It states, “A building must be protected from subterranean termites where the building is located in an area where subterranean termites are a hazard.” Australia is broadly classified as a termite hazard area, meaning these provisions apply universally unless specific local council mapping indicates otherwise (which is rare).

H4P1 (DtS Option): This pathway outlines acceptable construction practices and materials to satisfy the performance requirement. For slab-on-ground construction, as is common for kit homes, the DtS provisions in H4P1 (1) (d) refer directly to complying with AS 3660.1: Termite management – New building work or AS 3660.2: Termite management – In and around existing buildings and structures – Assessment and treatment for new buildings. While AS 3660.2 primarily addresses existing structures, its general principles may inform decisions for new builds in certain contexts. For new builds, AS 3660.1 is the primary reference. Furthermore, H4P1 (1)(d)(i) or (ii) specifically requires either a durable notice about the termite management system to be provided, or that the system is installed by a licensed pest controller or builder with appropriate training, and a certificate of installation issued.

The NCC also requires that access can be gained to inspect the building's subfloor and perimeter, or that a system that doesn't rely on future inspections to remain effective is installed (H4P1 (1)(b) and (c)).

Australian Standard AS 3660.1: Termite Management – New Building Work

AS 3660.1 is the seminal document guiding termite management in new construction. For slab-on-ground construction, it outlines various methods of protection designed to prevent concealed termite entry.

Key provisions relevant to slab edges generally fall under physical barriers or chemical barriers.

Physical Barriers (AS 3660.1, Section 5):

• Concrete Slabs (AS 3660.1, Clause 5.3): A concrete slab used as a termite barrier must comply with specific criteria. The slab itself, when forming a continuous barrier, must have no unstressed construction joints greater than 2 mm, and any stressed construction joints must be sealed. It must be continuous underneath all structural walls and piers. Most importantly for owner-builders, the external perimeter of the slab must be exposed for a minimum of 75 mm from finished ground level, forming a visual inspection zone. This 75 mm exposure is critical. If the slab edge is fully rendered or abutted by paving/landscaping, the visual inspection zone is lost, necessitating alternative or supplementary measures.
• Sheet Materials/Granular Barriers: Physical barriers, such as stainless steel mesh (e.g., Termimesh), galvanised steel mesh specifically designed for termite exclusion, or graded stone particulate barriers (e.g., Granitgard), are often used in conjunction with concrete slabs. These are typically installed at the slab edge, around penetrations, or as full under-slab barriers. When used at slab edges, they must be continuous, impervious to termite penetration, and durable for the design life of the building (typically 50 years).

Chemical Barriers (AS 3660.1, Section 6):

• Soil Treatment (AS 3660.1, Clause 6.3): This involves applying a termiticide to the soil around the perimeter of the building, creating a treated zone that deters or kills termites. For slab-on-ground, this often means treating the soil immediately adjacent to the slab edge. This method requires reapplication at specified intervals (typically 3-10 years, depending on the product) and is highly susceptible to disturbance by landscaping, drainage, or even prolonged heavy rainfall diluting the chemical.

State-Specific Variations and Regulatory Bodies

While the NCC provides the overarching framework, individual states and territories may have specific interpretations, preferred methods, or additional requirements enforced by their respective building regulatory authorities. It is crucial to consult these local bodies and local council requirements.

• New South Wales (NSW): Regulated by NSW Fair Trading / Department of Planning and Environment (DPE). NSW Building Code of Australia (BCA) provisions apply. Expect stringent enforcement of AS 3660.1, particularly regarding exposed slab edges and the durability of physical barriers. Owner-builders must engage a Certifier for all stages of construction, including termite management inspections.
• Queensland (QLD): Regulated by the Queensland Building and Construction Commission (QBCC). QLD places significant emphasis on the durability and maintenance of termite management systems. Due to the high prevalence of destructive termites, QLD often promotes robust physical barriers. Owner-builders must hold an Owner-Builder Permit and comply with relevant QBCC guidelines and BCA provisions.
• Victoria (VIC): Regulated by the Victorian Building Authority (VBA). The VBA enforces the NCC without significant state-specific variations for termite management beyond the general application. Building surveyors oversee compliance. Owner-builders require a Building Permit and, for larger projects, may need to meet specific knowledge and experience requirements.
• Western Australia (WA): Regulated by the Department of Mines, Industry Regulation and Safety (DMIRS). WA has historically had a high incidence of Mastotermes darwiniensis (Giant Northern Termite) in some northern regions, which are particularly aggressive. While less common in the south, the state generally adopts robust protections. Specific construction codes may incorporate WA-specific building tolerances or practices. Owner-builders need a Building Permit and must ensure compliance with the Building Act 2011 and Building Regulations 2012.
• South Australia (SA): Regulated by the South Australian Housing Trust (SAHT) and local councils. SA primarily follows the NCC/BCA. Termite management systems must be certified by a licensed PMP. Owner-builders must apply for a Building Consent or Approval from their local council or a private certifier.
• Tasmania (TAS): Regulated by the Department of Justice, Consumer, Building and Occupational Services (CBOS). TAS has a lower, though not absent, risk of subterranean termites compared to mainland states. However, NCC requirements still apply. Building surveyors manage compliance for owner-builders. Owner-builders must apply for a Building Permit.

In all states, any termite management system (physical or chemical) must be installed by a licensed pest management professional or a builder trained and accredited in installing the specific proprietary system, unless it's a 'Do-It-Yourself' barrier that explicitly states otherwise AND complies with AS 3660.1. Owner-builders must obtain a Certificate of Termite Treatment (or equivalent) confirming compliance, which must be part of the final building documentation.

Step-by-Step Process for Advanced Slab Edge Termite Management

This section outlines a detailed, advanced approach to integrating termite management into your slab-on-ground steel frame kit home foundation.

Step 1: Pre-Construction Planning and System Selection

1. Site Assessment and Risk Analysis:

   • Engage a local licensed pest management professional (PMP) to assess the site for historical termite activity, soil type, and other environmental factors. This initial consultation (approx. $150-$300 AUD) can inform optimal system selection. Some PMPs offer pre-construction advice.
   • Geotechnical Investigation: Your structural engineer will likely require a geotechnical report (soil test) for foundation design. This report (approx. $800-$2000 AUD) also provides valuable data on soil conditions crucial for chemical barrier longevity or physical barrier appropriateness.

2. Understand NCC & AS 3660.1 Options: Review AS 3660.1, Section 5 (Physical Barriers) and Section 6 (Chemical Barriers). For advanced applications, a physical barrier is generally preferred due to its permanence and reduced maintenance requirements.

3. Evaluate Proprietary Systems: Research, compare, and obtain quotes for various proprietary physical and chemical barrier systems. Examples include:

   • Stainless Steel Mesh: Termimesh, Altis.
   • Granular Barriers: Granitgard, HomeGuard (multi-layered PE/polymer membrane infused with termiticide for physical + chemical action).
   • Reticulation Systems (Chemical): TermX, Greenzone. These are buried piping systems that allow for periodic replenishment of termiticide without disturbing the landscape.
   • Sheet/Layered Barriers: Kordon, Biflex (often integrated into slab design).

4. Integration with Structural Design:

   • Crucial: Present your chosen termite management system to your structural engineer (or your kit home's engineer) before finalising slab designs. The system's requirements (e.g., dimensions, embedment depths, detail at re-entrant corners) must be incorporated into the structural drawings and specifications. For instance, some physical barriers require specific concrete cover or dedicated rebates.
   • Ensure drainage and landscaping plans are co-ordinated. The finished ground level (FGL) must be at least 75 mm below the top of the slab, exposing the slab edge, unless an approved alternative barrier protects this zone.

Step 2: Site Preparation and Pre-Slab Installation

1. Clearance and Grading: Clear the building footprint of all timber debris, roots, and foreign matter. Ensure the site is graded for positive drainage away from the future slab edge. Any potential 'hot spots' for termite activity should be identified and treated.

2. Underslab Preparation: If using a full under-slab physical membrane (e.g., HomeGuard Blue), ensure the subgrade is compacted and free of sharp protrusions that could puncture the membrane. A sand blinding layer (typically 50-100 mm) is often required. Ensure penetrations through the membrane for services are meticulously sealed as per manufacturer's instructions. This requires specialised sealing collars or tapes.

3. Perimeter and Penetration Treatment (Pre-Pour):

   • Physical Barriers: For systems like Termimesh, the mesh is custom-fabricated and installed around all service penetrations (pipes, conduits) before the concrete pour. For the slab edge, it's typically formed as a collar or integrated into the formwork, extending vertically and horizontally to create a continuous barrier. Ensure sufficient overlap and secure fixing as per AS 3660.1 and manufacturer guidelines. For granular systems, the barrier is precisely placed in trenching around the perimeter.
   • Chemical Barriers (Pre-Construction Soil Treatment): If opting for a chemical barrier, a licensed PMP will apply a termiticide to the soil directly beneath the slab area and around the perimeter of the building footprint before the concrete is poured. This creates a treated zone. Pay close attention to dosage rates and uniform application. This must be done immediately prior to pouring to prevent disturbance. Cost: $18-$35 AUD per lineal metre for perimeter, $12-$25 AUD per sqm for under-slab, depending on chemical and application depth.

WHS Warning: Chemical termiticides are hazardous. Only licensed professionals should handle and apply them. Owner-builders overseeing this must ensure strict adherence to Material Safety Data Sheets (MSDS) and Personal Protective Equipment (PPE) requirements (gloves, respirators, eye protection). Consider wind direction and exclusion zones from waterways/drainage. Record all treatments diligently.

Step 3: Slab Pour and Curing

1. Protection During Pour: Exercise extreme caution during concrete placement and screeding to avoid dislodging or damaging installed physical barriers or disturbing treated soil. Vibrators must be kept away from penetrations where barriers are installed.

2. Formwork Removal: Care must be taken during formwork removal to not damage the exposed slab edge. Any chips or spalls >2mm must be repaired with a suitable non-shrink grout or epoxy, specifically addressing potential termite entry points.

Step 4: Post-Slab & Slab Edge Detailing

1. Exposed Slab Edge: The NCC and AS 3660.1 mandate a minimum 75 mm visually inspectable slab edge from finished ground level to the top of the slab. This is a critical detection zone. Any landscaping, paving, or pathways must be designed and constructed to maintain this 75 mm clear zone.

   • Advanced Detail: If the 75 mm exposure cannot be maintained due to architectural design or site constraints (e.g., zero-lot line construction or direct abutment by paving), then a secondary, durable, and inspectable termite barrier must be incorporated. This might involve:
     • Vertical Physical Barrier: Extending a robust physical barrier (e.g., stainless steel mesh, specifically designed termite-resistant flashing) vertically upwards from the original under-slab barrier, integrated into the cladding and providing a visible perimeter inspection strip at a higher level. This typically means detailing the cladding to be installed 75mm above the finished ground level, exposing the barrier.
     • Reticulation System: Installing a subsurface reticulation system directly underneath the paving/landscaping, which allows for re-dosing with termiticide without disturbing hard surfaces. This system's recharge points must be marked and readily accessible.
     • Integrated Masonry/Cladding Detail: For brick veneer or other cladding systems, ensure the base course of masonry or cladding is constructed such that the weep holes are above the 75mm inspection zone, and that no concealed path exists from ground to timber frame behind the cladding. A termite-proof flashing or damp-proof course (DPC) designed as a barrier should be integrated at the base of the wall framing above the slab.

2. Sealing of Penetrations: All service penetrations through the slab (plumbing, electrical, data) must be individually sealed with an approved termite barrier, even if a full under-slab barrier or perimeter treatment was installed. These are highly vulnerable points. Options include:

   • Proprietary Collars: Specific termite collars (e.g., from Termimesh, Kordon) are designed to fit around pipes and services, mechanically fastened or bonded to the slab surface and sealed. These are applied after the pour but before internal linings.
   • Chemical Application: Spot treatment of penetrations by a PMP with an approved termiticide. Requires periodic re-treatment.
   • Specific Sealants: Use of termite-resistant elastomeric sealants or foams specifically approved for sealing gaps around penetrations, in conjunction with other barriers.

3. Backfill and Landscaping: Use non-susceptible materials (e.g., sand, gravel, engineered fill) for backfill around the perimeter. Avoid placing timber garden beds or landscaping timbers directly against the slab edge. Maintain clear visibility of the 75 mm slab edge. Allow for future soil settlement; if any settlement bridges the 75 mm gap, it must be rectified immediately.

Step 5: Certification and Ongoing Maintenance

1. Certificate of Treatment: Upon completion of the termite management system installation, obtain a Certificate of Termite Treatment or Statement of Compliance from the licensed PMP or accredited installer. This certificate must detail the system used, areas treated, chemical used (if applicable), warranty period, and re-treatment/inspection requirements. This document is essential for your building permit finalisation and future sale of the property.

2. Durable Notice: AS 3660.1 requires a durable notice (often a metal or plastic plate) to be permanently fixed in a prominent location within the building (e.g., meter box, laundry cupboard, under kitchen sink). This notice must state:

   • Method of termite management.
   • Date of installation.
   • Date of required re-inspection/re-treatment.
   • Installer's details.

3. Ongoing Inspections: Regardless of the system type (even permanent physical barriers), AS 3660.2 recommends annual visual inspections by a licensed PMP. This is vital because building defects, landscaping changes, or material degradation can compromise even the best systems. The owner-builder is ultimately responsible for maintaining the effectiveness of the system.

Practical Considerations for Steel Frame Kit Homes

While steel frames offer inherent termite resistance, their integration within a complete building requires specific considerations for slab edge termite management.

1. Steel Frame Base Plate Detailing: The steel frame typically sits on a damp-proof course (DPC) on the concrete slab. Ensure this DPC is continuous and doesn't create gaps where termites could establish concealed entry. For proprietary steel frame systems (e.g., TRUECORE® based framing with specific connection details), ensure any penetration through the DPC (e.g., anchor bolts) are sealed or protected.

2. Cladding Systems: The interface between the steel frame, slab edge, and external cladding is a critical zone. Many common cladding systems (e.g., fibre cement sheeting, render, brick veneer, timber weatherboards) can conceal termite tunnels if not correctly installed. AS 3660.1 Section 5.3.3 (Concrete Slabs as Barriers) explicitly states that if the slab edge is rendered or clad below FGL, the visual inspection zone is compromised, requiring the incorporation of a specific termite management system in that area.

   • Brick Veneer: For steel frame homes with brick veneer, the cavity provides a concealed path. Termite barriers must extend into the cavity or a termite 'flashing' (physical barrier) must be incorporated at slab level and above the weep holes, extending from the timber/steel frame DPC outwards past the brickwork, effectively creating a barrier in the cavity.
   • Render/Lightweight Cladding: When render or lightweight cladding extends all the way to ground level, a termite barrier must be installed beneath this cladding, exposed for part of its length or otherwise inspectable, or a reticulation system must be incorporated for ongoing chemical treatment.

3. Decking and Pergolas: Timber decking or pergolas attached to the steel frame house provide bridging points. Ensure any timber posts are either termite-resistant (H5/H6 treated timber or steel posts) or have compliant termite collars/stumps. The decking should be sufficiently separate from the house (e.g., 25-50 mm gap) or have a continuous termite barrier installed at the junction.

4. Service Ducts and Risers: For multi-level kit homes or homes with extensive service networks, vertical service risers or ducts from the ground floor slab are significant termite entry points. Each penetration into these areas must be treated similarly to slab penetrations, with collars or continuous physical barriers up the shaft. For steel frame systems, the services are typically routed within the frame, but entry points from the slab remain critical.

5. Long-term Durability for Steel Components: While the steel framing (e.g., from BlueScope Steel) is termite-proof, ensuring proper galvanisation (e.g., Z275 minimum) and avoiding situations that compromise this (e.g., cutting and not cold galvanising, prolonged exposure to harsh chemicals) is vital for the frame's overall longevity. This does not directly relate to termite entry but to the general durability of the home. The same diligence applied to termite barriers should be applied to protecting the framing's integrity.

Cost and Timeline Expectations

Accurate cost and timeline projections are essential for owner-builders. These figures are indicative and can vary significantly based on location, site conditions, system chosen, and chosen PMP/installer.

Cost Estimates (AUD, current as of late 2023 - early 2024)

Total Estimated Cost Range for a Typical Kit Home (150-200 sqm slab footprint):

• Basic Chemical Perimeter: $1,500 - $3,500 (plus re-treatment every 3-10 years)
• Basic Physical Perimeter Barriers (e.g., membrane + collars): $2,500 - $6,000
• Comprehensive Physical Barrier (under-slab membrane + detailed perimeter & penetrations): $4,000 - $10,000+
• Reticulation System: $3,000 - $7,000 (plus re-dosing costs)

These costs are for supply and installation by a licensed professional. DIY aspects might reduce initial outlay but often void warranties or fail to meet compliance without expert oversight.

Timeline Expectations

• Planning & Quotes (Step 1): 2-4 weeks (concurrent with engineering and permit applications)
• Site Preparation (Step 2.1): 1-3 days
• Pre-Slab Barrier Installation (Step 2.2-2.3):
  • Chemical Treatment: 0.5-1 day (applied just before pour)
  • Physical Barriers (membrane, mesh, collars): 1-3 days (depending on complexity and system)
• Slab Pour & Curing (Step 3): 1-2 days for pour, 7-28 days for curing (not direct termite work time, but a necessary pause)
• Post-Slab Detailing (Step 4): 1-2 days (e.g., applying external collars, final perimeter checks)
• Certification (Step 5): Day of completion and sign-off by PMP.

Integration into Overall Build Timeline: Termite management is an early-stage activity, typically occurring just before and after the concrete slab pour. Delays in this stage can impact subsequent framing and lock-up stages.

Common Mistakes to Avoid

Even experienced owner-builders can fall victim to common pitfalls:

1. Ignoring the 75 mm Visual Inspection Zone: This is the most common non-compliance issue. Landscaping, garden beds, paving, or external render extending up against or over the slab edge obliterates the inspection zone. This creates a concealed path for termites, rendering existing barriers ineffective and making detection impossible until significant damage has occurred. Always maintain the 75 mm exposed zone, or explicitly install an approved, inspectable secondary barrier where this is not possible.

2. DIYing Proprietary Systems without Accreditation: While owner-builders are empowered to do much, installing proprietary termite management systems (e.g., specific membranes, reticulation systems, or chemical barriers) often requires specific manufacturer accreditation and licensing as a PMP. Attempting DIY installation without this expertise will void warranties, likely fail to meet AS 3660.1, and prevent your building surveyor/certifier from issuing compliance. Always use licensed professionals for proprietary system installation.

3. Damaging Barriers During Construction: Post-pour activities (e.g., backfilling, service trenching, landscaping) can easily damage chemical treated zones or rupture physical barriers (membranes, meshes). Exercise extreme care, mark barrier locations clearly, and provide explicit instructions to all trades (plumbers, electricians, landscapers) working around the perimeter and penetrations. Damage must be immediately repaired by a licensed PMP or accredited installer.

4. Neglecting Service Penetrations: Many owner-builders focus on the perimeter but overlook the myriad of pipes, conduits, and cables penetrating the slab. Each one of these is a potential entry point and must be individually protected with approved collars, physical barriers, or chemical spot treatments. A comprehensive barrier under the entire slab is the best solution but relies on perfect sealing at penetrations.

5. Assuming Steel Frames are 'Termite-Proof': As discussed, while steel itself is resistant, the building as a whole is not. This false sense of security can lead to complacency in implementing and maintaining termite management, exposing all non-steel components to risk. Remember, the NCC dictates protection for the building, not just the core structure.

6. Lack of Documentation and Regular Inspections: Failing to obtain a Certificate of Termite Treatment, forgetting to place the durable notice, or neglecting annual inspections leaves you vulnerable. These documents are proof of compliance and essential for future property transactions. Regular inspections, even with robust physical barriers, are crucial to detect breaches or new paths.

7. Inadequate Drainage: Poor site drainage leading to perpetually damp soil around the perimeter encourages termite activity. Ensure proper grading, stormwater management, and possibly subsoil drainage to keep the critical inspection zone and perimeter relatively dry.

When to Seek Professional Help

Even for advanced owner-builders, specific aspects of termite management demand specialist expertise:

1. System Design and Selection: While you can research, a licensed Pest Management Professional (PMP) or a specialist termite management consultant brings invaluable experience in selecting the most appropriate system for your specific site conditions, local termite pressures, and budget. They can also advise on the nuances of AS 3660.1 applicability.

2. Proprietary System Installation: As noted, most physical and all chemical systems require installation by licensed PMPs or accredited installers. Attempting this yourself could lead to non-compliance, invalidated warranties, or ineffective protection. This includes detailed installation of specific membranes, meshes, collars, and reticulation systems.

3. Chemical Application: The application of termiticides is dangerous and heavily regulated. It must be performed by a fully licensed PMP. Owner-builders should never attempt to apply professional-grade termiticides themselves.

4. Complex Junctions and Details: Architectural features, re-entrant corners, split-level slabs, attached amenities (decks, carports), or complex service penetrations often require tailored solutions beyond standard detailing. PMPs or structural engineers with experience in termite management can design these critical junctions.

5. Compliance Certification: Your building surveyor/certifier will require a Certificate of Termite Treatment from a qualified professional to issue occupancy permits. This is non-negotiable.

6. Annual Inspections and Re-treatments: Ongoing annual inspections are best left to licensed PMPs who possess the knowledge and equipment to detect termite activity early and recommend appropriate action.

Checklists and Resources

Pre-Construction Checklist

• Engaged licensed PMP for site assessment and consultation.
• Received and reviewed geotechnical report.
• Researched and selected preferred termite management system(s) (physical, chemical, or combination).
• Obtained quotes from licensed installers for selected system(s).
• Integrated termite management details into structural engineering drawings.
• Reviewed proposed landscaping/drainage plans for compliance with 75mm slab edge exposure.
• Confirmed state-specific requirements with local building authority/certifier.

During Construction Checklist (Pre-Slab)

• Site cleared of all timber debris and roots.
• Subgrade compacted and free of sharp objects for membrane installation.
• PMP/accredited installer booked for pre-pour barrier installation.
• Confirmed all service penetrations marked for treatment with collars/barriers.
• Ensured safe access and adequate working space for PMP/installer.
• Reviewed PMP's WHS plan for chemical applications (if applicable).

During Construction Checklist (Post-Slab & Final)

• Ensured concrete pour did not damage barriers/treated zones.
• Inspected slab edge for spalling/chips >2mm and arranged repairs if needed.
• Confirmed 75 mm visual inspection zone is maintained around entire perimeter.
• Ensured all service penetrations have compliant termite collars/seals.
• Arranged for PMP final inspection and Certificate of Termite Treatment.
• Ensured durable notice is affixed in a prominent location.
• Reviewed final landscaping plans to prevent compromising barriers or inspection zones.

Useful Resources & References

• National Construction Code (NCC) 2022, Volume Two: Accessed via ABCB website (www.abcb.gov.au). Focus on H1V5, H4P1.
• AS 3660.1: Termite management – New building work: Available for purchase from Standards Australia (www.standards.org.au). Essential reading.
• AS 3660.2: Termite management – In and around existing buildings and structures – Assessment and treatment: Also from Standards Australia, useful for ongoing maintenance.
• State Building Authorities:
  • NSW Fair Trading: www.fairtrading.nsw.gov.au
  • QBCC (QLD): www.qbcc.qld.gov.au
  • VBA (VIC): www.vba.vic.gov.au
  • DMIRS (WA): www.commerce.wa.gov.au/building-and-energy
  • SA Housing Trust / Planning Portal (SA): www.sa.gov.au/topics/planning-and-property/building-and-development
  • CBOS (TAS): www.cbos.tas.gov.au
• BlueScope Steel and TRUECORE®: For technical specifications and guidance on steel framing: www.bluescopesteel.com.au
• Australian Environmental Pest Managers Association (AEPMA): For finding licensed pest contractors: www.aepma.com.au

Key Takeaways

Slab edge termite management for your steel frame kit home is a multifaceted, critical component demanding meticulous planning and execution. While steel frames are resistant, the building's overall vulnerability to termites requires adherence to the NCC and AS 3660.1. Prioritising permanent physical barriers, ensuring a continuous 75 mm visual inspection zone (or an approved alternative), and expertly treating all slab penetrations are paramount. Engaging licensed pest management professionals for installation and seeking certification are non-negotiable for compliance and long-term protection. Owner-builders must actively coordinate all trades, maintain vigilant oversight, and commit to ongoing inspections to safeguard their significant investment against the pervasive threat of subterranean termites. Do not compromise on these details; they represent the true foundation of your home's enduring integrity.