Inner West · AS 3660.1
Under-slab and perimeter barriers installed to the pour date for Annandale 2038 terrace rebuilds and rear extensions on the grid of streets off Johnston Street.
Quick answer
Even a rear extension or rebuilt terrace in Annandale needs a termite management system, because Inner West Council treats the area as termite prone and will not sign off an Occupation Certificate otherwise. The NCC requirement is installed to AS 3660.1 after plumbing rough-in and before the new slab section is poured. A durable notice and an installation certificate then follow for the certifier.
Termite barriers in Annandale
Annandale is a compact Inner West Council suburb about 3.7 km south-west of the CBD, in postcode 2038, with streets running in a neat grid off Johnston Street and Booth Street. Victorian terraces, semi-detached cottages and some unusual late-1800s houses, including the Gothic Revival mansions known locally as the witches' houses, line those streets, and Parramatta Road forms the southern edge as the suburb slopes north toward Rozelle Bay and the light rail. New building work here is almost always a terrace rebuild, a rear addition or a laneway extension rather than a fresh block, since so little vacant land remains.
That pattern of tight, shared-wall building is what shapes the barrier work in Annandale. Terraces share party walls and roof spaces, and many stand on shallow sub-floors that have to be worked around when a new slab section is poured for an extension. Decades of rear-yard renovation have left gaps around pipes and eaves on plenty of these homes, so a new slab tying into an old structure needs the collar and perimeter detail done carefully at that particular join, not just around the new work's own outer edge alone.
Reviewed by Ismail, founder · Inner West coverage · Updated September 2026 · More Inner West suburbs
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Local conditions
Three things matter most when detailing a barrier for an Annandale terrace.
Terraces and semi-detached cottages share walls and sometimes roof spaces with their neighbours, so a new slab section for a rear extension has to be sealed carefully at the party-wall junction. A gap left there can give termite activity a route between properties.
Many Annandale terraces sit on shallow, original sub-floors that a rear extension's new slab has to tie into. That transition gets specific attention from us, since a rushed partial rebuild is exactly where this kind of junction gets skipped over.
With almost no vacant blocks left, nearly all new termite work here is a rear addition, laneway extension or full terrace rebuild on an existing footprint. Each of these still needs its own compliant system under the NCC, sized to the new slab area rather than a whole new house.
What we install here
Our Annandale work is mostly rear extensions, laneway additions and full terrace rebuilds, with the occasional larger corner-block knockdown. We detail collars and perimeter systems around existing party walls and sub-floors as much as new slab edges, and we schedule the visit around the plumber's rough-in for the new work so it fits between that and the pour. One fixed quote from the plans covers the job, whatever mix of new and existing structure it involves.
Local knowledge
Jobs closer to Parramatta Road tend to be rear extensions on the older terrace stock, where tying the new slab into an existing party wall is the main detail to get right. Toward Rozelle Bay and the light rail, blocks slope more and renovation work has to account for that fall as well as the usual terrace constraints. Badu Park adds a small green pocket near the suburb centre, and older garden beds around it are worth checking on any block backing onto it.
Inner West Council is the certifying authority for Annandale, and getting to an Occupation Certificate means having two things ready: signage permanently fitted in the meter box describing the system, plus a certificate recording the products used, the areas covered and the installer's details. On terrace rebuilds we also note how the new work ties into the existing structure for the certifier's records.
Annandale at a glance
| Suburb | Annandale, NSW 2038 |
|---|---|
| District | Inner West |
| Distance from Sydney CBD | 3.7 km south-west |
| Certifying council | Inner West Council |
| Standard applied | AS 3660.1 termite management systems |
| Installed | Before the slab pour, then staged through the build |
| Documents supplied | Installation certificate and durable notice |
| Typical builds covered | New homes, knockdown rebuilds, granny flats, duplexes, townhouses |
Systems we install
Every photo below is from one of our own Sydney jobs. We look at your slab design, site and budget, then recommend a system or a combination.
01A termite-resistant sheet laid over the whole prepared footprint before concreting, so termites can't come up through the slab anywhere.
02A sealed collar on every pipe, conduit and service that passes through the slab. These gaps are the most common hidden way in.
03Protection at the slab edge and into the wall cavity, which stops termites building hidden tunnels up the outside of the slab.
04An APVMA-registered termiticide zone in the soil, with an optional pipe network under paving so it can be recharged later without digging.
05Barriers for bearers, piers and raised timber floors on sloping or elevated blocks, where there's no slab to protect.
06Detailing for sandstone cuts, block retaining walls, step-downs and cut-and-fill sites, which are common across Sydney.
Why during construction
A retrofit can only treat around a finished house. A pre-construction system protects the parts nobody will ever be able to reach again.
A barrier put in during the build costs a fraction of a post-construction system, and far less than repairing termite damage.
New houses (Class 1) and outbuildings (Class 10) with termite-susceptible framing need a compliant termite management system.
Pipe penetrations and slab joints can only be fully protected while they're still open, before the concrete goes in.
An under-slab system covers ground that no treatment from outside the finished house can ever reach.
Your certifier needs the certificate and durable notice before issuing the Occupation Certificate. We supply both together.
Documented, compliant protection gives buyers, building inspectors and lenders confidence when the home is sold.
Installation stages
A termite barrier isn't a single visit. Each part goes in when the site is ready for it, and we fit around your plumber, concreter and bricklayer.
Send your plans and slab details. We recommend a system and give you one fixed price that covers every stage.
Collars go on every service once the plumber has set out, then the membrane or soil treatment is installed across the prepared site.
Perimeter and cavity protection is fitted as the brickwork or cladding goes up, so there's no unprotected gap at the slab edge.
Where it's specified, the chemical perimeter or reticulation system is completed around the building before paths and gardens go in.
A durable notice goes in the meter box, and the installation certificate goes to your builder and certifier.
The owner gets simple care instructions and an inspection schedule so the system keeps doing its job for years.
Compare systems
Both can meet AS 3660.1. The best choice depends on your slab type, what surrounds the house and how much ongoing upkeep the owner wants.
Physical protection
Entry-point protection
Soil protection
Top-up protection
Most of the Sydney builds we work on use a combination: physical collars on every penetration plus a physical or chemical perimeter.
For builders & developers
Builders, developers and owner-builders get a fixed quote from plans, a technician who turns up when the site is ready, and paperwork that never holds up sign-off.
Consistent pricing across lots, one point of contact and a full document set for every dwelling.
Missing durable notices and unclear install records are a common reason Occupation Certificates get held up. We hand everything over together so your certifier has it all in one go.
Paperwork
A complete document set for the builder, the certifier and every future owner of the property.
A permanent notice in the meter box showing the system, install date, installer, any chemical's life expectancy and inspection advice.
For: certifier, owner, future owners
Written confirmation of the system and products used, the areas protected and our licence details.
For: builder, certifier, owner
Details of the physical system or termiticide installed, including safety data sheets for any chemicals.
For: builder, owner
How to keep the system working, plus the recommended inspection frequency under AS 3660.2.
For: homeowner
From real jobs
Photos from our own Sydney sites, not stock images. Tap any photo to see it larger.
Membrane barrier across a large residential slab
Barrier work on a Sydney Harbour site
Installation through sandstone excavation
Perimeter barrier and sleeves on a new slab
Waffle pod formwork with collared penetrations
Membrane detailed against a retaining wall
Membrane sealed around a column
Protected slab edge with collar in place
Collared penetrations before the pour
Perimeter barrier on a completed slab edge
Pipe penetrations sealed into the membrane
Collars fixed through mesh before concreting
Google reviews
Real, verified reviews from homeowners and businesses we've worked with.
Pricing
Every build is different, so we don't guess. We price from your plans and give you one fixed written quote. Quoting is free.
After handover
A barrier only works while it stays intact and visible. Pass these on to the owner.
Free fixed quote
Tell us about your build and get a clear, fixed price, fast. We usually reply within 30 minutes during business hours.
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Annandale questions
Still unsure? Call and talk it through with a licensed technician.
+61 450 515 215Yes. A rear extension counts as new slab area under the NCC and needs its own compliant coverage regardless of the original terrace's protection. Our visit is timed to the plumber's rough-in for that work, and the new perimeter is tied into the existing terrace's system at the party wall or sub-floor junction, wherever the two meet.
A full rebuild behind a retained facade or party wall is treated like a new home for the new slab area, with collars at every penetration and a perimeter system matched to how the rebuild is footed. We pay particular attention to the junction with the neighbouring terrace, since that is where gaps are most often missed.
Yes. Laneway additions and rear lane garages still count as new structures under the NCC and need their own termite management system. We size the collar and perimeter work to the addition's footprint and issue a separate durable notice and certificate for it if it is titled as a distinct structure.
In most cases, yes. The National Construction Code requires a termite management system for new houses and outbuildings in termite-prone areas where the primary building elements can be damaged by termites. Sydney is termite-prone, so the system is installed to AS 3660.1 and your certifier asks for the installation certificate and durable notice before the Occupation Certificate is issued.
It depends on slab area, perimeter length, the number of pipe penetrations, the system chosen, site complexity and how many visits the build needs. Send us the plans and we return one fixed written quote covering every stage. Quoting is free.
Nearby
Same crew, same staging and the same certifier-ready paperwork, right across the Inner West.
Service areas
From the Eastern Suburbs and Inner West to the Hills, the Shire and the western growth corridors. Every suburb has its own page with the local ground conditions, the council that certifies the work and the questions builders there ask us.
Slab pour coming up?
Send us your plans today for a fixed quote, or call and talk to a licensed technician about your site.
