Pest-Proofing Your Premises: Sealing Entry Points

Pest-proofing a food premises starts by sealing the gaps, cracks and service penetrations that let rodents, insects and birds get inside. Walk the building inside and out, seal openings wider than about six millimetres, fit door sweeps and screens, and close the gaps around pipes, cables, drains and vents. Denying pests entry is the most reliable, chemical-free way to protect food and meet your obligations under the Food Standards Code. Key takeaways: Exclusion — physically sealing entry points — is the foundation of pest control and works around the clock without chemicals or bait.. Rodents can enter through gaps as small as a pencil width, so seal openings of roughly six millimetres or more, and close every service penetration around pipes, cables and drains.. Inspect the whole building envelope inside and out, low and high, because pests exploit doors, vents, roof lines, wall junctions and utility entries.. Use durable, pest-resistant materials such as steel wool packed into gaps, metal mesh, concrete or proper sealant — not expanding foam alone, which rodents chew through.. Standard 3.2.3 requires premises to be designed and maintained to exclude pests; sealing is a repair-and-monitor cycle, not a one-off job.. Why sealing entry points comes first Pest control is often pictured as bait stations and sprays, but those are a response to pests that have already arrived. Exclusion — physically stopping pests getting in — is the first and most effective layer, because a gap that is sealed keeps working every hour of every day with no chemicals, no bait to replenish and no residue near food. Traps and treatments manage the pests you already have; sealing prevents the next ones. The stakes in a food business are high. Rodents, cockroaches, flies and birds carry pathogens, contaminate surfaces and food with droppings, urine and faeces, and can trigger a serious contamination incident or a failed inspection. A single mouse squeezing through a gap under a delivery door can foul a dry store overnight. Sealing also reduces your reliance on chemical control near food, which is safer for staff and customers and simpler to manage. When you handle pesticides, treat them as hazardous chemicals and follow the label and safety data sheet. The less you need them, the better. How pests actually get in Pests are opportunists that exploit the smallest weaknesses in a building. Understanding their capabilities tells you what to look for. A mouse can pass through a gap around six millimetres wide — roughly a pencil width — and rats through gaps not much larger. Insects need only a hairline crack, and flying insects pour through any unscreened opening. The most common entry points cluster in predictable places. Working through them systematically catches far more than a casual glance. Gaps under and around external doors, especially roller and delivery doors. Service penetrations where pipes, conduit, cables and gas lines pass through walls. Floor and wall drains, grease traps and unsealed floor-wall junctions. Ventilation openings, extraction ducts and roof vents without mesh. Cracks in walls, rendering and around window frames. Gaps at the roof line, eaves, and where wall panels meet. Damaged fly screens, and windows left open without screens. Inspecting the building envelope Effective sealing depends on a thorough inspection, so treat the whole building envelope as your map. Walk the exterior perimeter slowly, then the interior, and look low and high — pests travel along floors and skirting but also climb pipes, cables and rough walls to reach roof spaces and upper openings. A torch helps reveal daylight showing through gaps from inside a dark store. Look for the tell-tale signs alongside the gaps themselves. Rub marks and grease trails along walls, gnaw marks on timber or plastic, droppings, and disturbed dust all point to active runs and the openings that feed them. Follow the evidence to the entry point rather than sealing at random. Pay particular attention to areas that are hard to see and rarely cleaned: behind and under equipment, inside cavities, around the backs of cool rooms, and above false ceilings. These sheltered spots are exactly where pests prefer to travel, and where an unsealed penetration can go unnoticed for months. Sealing methods and materials that last The material you choose decides whether a repair holds. Rodents gnaw persistently, so soft fillers alone fail. Expanding foam on its own is a common mistake — mice chew straight through it. The reliable approach is to pack a gnaw-resistant material into the gap and finish it so it is durable and cleanable. Match the material to the opening. Small to medium gaps around pipes can be packed tightly with stainless or coarse steel wool, then sealed over with a suitable sealant or mortar. Larger holes need metal sheet, hardware cloth or wire mesh, or filling with concrete or cement. Cracks in walls and around frames take a food-premises-appropriate sealant. Whatever you use, the finished repair should be smooth and washable so it does not become a dirt trap. For moving openings, the fittings differ. Fit close-fitting door sweeps and brush strips to the base of external doors, weather seals around frames, and metal kick plates where rodents gnaw at door bottoms. Screen every opening window and every vent or duct with fine, durable mesh that still allows airflow. Doors, windows, vents and drains Doors are the single biggest weak point because they open constantly and rarely seal perfectly. External and delivery doors should be self-closing where practical, fitted with sweeps that leave no visible gap at the base, and kept shut when not in active use. Propping a back door open during a busy service is one of the most common ways pests walk in. Windows and ventilation openings are the entry route for flying insects and, higher up, for birds and rodents using pipes and cables to climb. Any window that opens needs an intact, well-fitted fly screen. Vents, extraction outlets and roof openings should be meshed with a gauge fine enough to stop insects but robust enough to resist rodents. Drains and floor-wall junctions are easy to overlook and heavily used by pests, especially cockroaches and rodents that travel through drainage. Fit drain covers or grates, keep them in good repair, and seal the junctions where floors meet walls so there is no continuous gap running behind equipment and skirting. What the Food Standards Code expects Food safety requirements in Australia sit under the Australia New Zealand Food Standards Code. Standard 3.2.3 (Food Premises and Equipment) requires premises to be designed, constructed and maintained so that pests can be effectively controlled and, as far as practicable, prevented from entering and harbouring on the premises. Standard 3.2.2 (Food Safety Practices and General Requirements) adds the ongoing duty to take practicable measures to prevent pests on the premises. Sealing entry points is a core way you meet both. The Code focuses on the outcome rather than prescribing a single method: the building must exclude pests and be kept in a condition that continues to do so. That makes sealing a maintenance cycle, not a one-off task. Buildings move, seals perish, new penetrations get drilled for equipment, and fresh gaps appear, so inspect and repair on a regular schedule and keep records of what you find and fix. Adoption and enforcement of the Code happen through state and territory legislation, and inspections are usually carried out by local councils. Exact expectations and how they are applied vary by location, so confirm the specifics for your business with your local council or state regulator rather than assuming one national approach. Checklist: External and delivery doors have close-fitting sweeps and no visible gap at the base. Every service penetration around pipes, cables, conduit and gas lines is sealed. Gaps of roughly six millimetres or wider are packed with steel wool or mesh and finished. Opening windows have intact, well-fitted fly screens. Vents, ducts and roof openings are meshed with durable fine gauge. Drains have covers or grates in good repair and floor-wall junctions are sealed. Cracks in walls, rendering and around frames are filled with suitable sealant. Repairs are smooth, durable and cleanable rather than temporary. A recurring inspection and repair schedule is in place and records are kept. Local council or state regulator requirements have been confirmed. Common mistakes: Relying on bait and sprays while leaving the entry points that let pests in unsealed. Using expanding foam on its own, which rodents chew straight through. Sealing obvious ground-level gaps but ignoring roof lines, vents and high penetrations pests climb to. Propping delivery or back doors open during service, undoing the sealing work. Overlooking drains and floor-wall junctions, a favourite route for cockroaches and rodents. Treating sealing as a one-off job rather than a scheduled inspect-and-repair cycle. Leaving repairs rough and unsealed so they become dirt traps that are hard to clean.