Deck Builders North Shore Sydney
UrbanArch are the deck builders North Shore homeowners call when the block isn’t flat.
North Shore backyards are rarely flat and rarely simple. Most of the decks we build between Mosman and Wahroonga sit on a fall, back onto bushland, or have to work around trees nobody is allowed to touch. That’s the work we’re set up for.
UrbanArch is a father-and-son business — Tony and Dean. The bloke who quotes your job builds your job. Twenty years on the tools, company established 2017, and a 10-year workmanship warranty on everything we build.
What makes a North Shore deck different
Three things come up on nearly every North Shore job:
The fall. Blocks through Northbridge, Castlecrag, Lane Cove and the Ku-ring-gai suburbs drop away hard behind the house. That means a raised deck on posts and piers rather than a slab-level platform — and once you’re more than a metre off the ground, you’re into compliant balustrades, engineered footings and a set of stairs that has to be built properly rather than bolted on afterwards.
The trees. Ku-ring-gai and Willoughby have some of the most protected canopy in Sydney. Digging inside a tree protection zone, or lopping a branch to fit a deck, can turn a straightforward job into a council problem. We design around root zones and set out footings to avoid them, rather than finding out mid-dig.
The bush. Anything backing onto reserve through St Ives, Turramurra, Wahroonga or the Hornsby fringe is likely on bushfire-prone land, and that dictates what you’re allowed to build with.
Raised decks, stairs and balustrades for steep blocks
On a sloping site the deck is only half the job — the structure underneath it and the way you get down to the yard matter just as much.
We build on H4-treated hardwood or steel substructure with stainless fixings, sized to the span and the height. Where a deck sits more than a metre above ground, balustrades have to meet the National Construction Code, which sets a minimum 1m height and limits gaps so a 125mm sphere can’t pass through. We build them in matching timber, powder-coated aluminium, or glass where you don’t want to lose the view — which is the usual answer in Mosman and Northbridge.
Stairs on a fall need consistent rise and going the whole way down, landings where the run is long, and footings that won’t move. We do them as part of the deck, not as an afterthought.
Building beside bushland — BAL ratings and fire-rated decking
On a sloping site the deck is only half the job — the structure underneath it and the way you get down to the yard matter just as much.
We build on H4-treated hardwood or steel substructure with stainless fixings, sized to the span and the height. Where a deck sits more than a metre above ground, balustrades have to m
If your property is mapped as bushfire-prone, your deck needs to meet a Bushfire Attack Level. Most bush-backed North Shore blocks land somewhere between BAL-12.5 and BAL-29, and that limits you to fire-resistant timbers or approved composite systems.
Above BAL-29, standard timber and most composites are out. That’s where we use Knotwood aluminium decking — it looks like timber, it’s non-combustible, and it holds up in the high-BAL zones through Ku-ring-gai and Hornsby where nothing else is compliant.
We’ll check the bushfire-prone land map for your address before we quote, so the material conversation happens up front rather than after council knocks it back.
eet the National Construction Code, which sets a minimum 1m height and limits gaps so a 125mm sphere can’t pass through. We build them in matching timber, powder-coated aluminium, or glass where you don’t want to lose the view — which is the usual answer in Mosman and Northbridge.
Stairs on a fall need consistent rise and going the whole way down, landings where the run is long, and footings that won’t move. We do them as part of the deck, not as an afterthought.
A recent job — Trex deck and staircase in Pymble
What the owners had to say
They paid great attention to even the smallest details, ensuring that everything was perfect. The project was finished on time and exceeding my and my wife’s expectations.
I highly recommend these guys to anyone looking for high-quality work. Their skill, dedication, and professionalism really set them apart!
What we did
This Pymble home had two levels of tired hardwood decking and a steep timber staircase tying them together. Years of Ku-ring-gai leaf litter and shade had left the boards grey and lifting, the lattice screening was on its way out, and the stairs had become the part of the house nobody wanted to use after rain. The owners wanted the same layout — they liked how the deck worked — just built properly and finished in something they’d never have to sand or oil again.
We rebuilt both levels in Trex Island Mist, a soft grey composite with a variegated grain that sits well against the surrounding bush and doesn’t wash out in full sun. The connecting staircase was rebuilt from the ground up on an H3-treated timber substructure and clad in the same Island Mist boards, so the two levels read as one deck rather than two separate builds. On the lower deck and right up the staircase we installed Ultralox aluminium handrail and balustrade in white — powder-coated, welded aluminium, and completely maintenance-free, which is the point on a two-storey structure you can’t easily get a ladder to. The upper level was finished in frameless glass balustrade to keep the treetop outlook the owners bought the house for.
The result is a two-storey deck that meets the required balustrade heights and non-climbable zones, handles a shaded, damp North Shore block without cupping or splintering, and needs nothing more than an occasional hose-off. It’s the kind of build we do a lot of across Pymble, St Ives, Turramurra and Wahroonga — established homes on sloping, tree-covered blocks where the deck has to work hard and the setting deserves a finish that lasts.
Lower North Shore: Mosman, Cremorne, Neutral Bay, Kirribilli, Northbridge, Castlecrag, Willoughby, Naremburn, Artarmon, Chatswood, Lane Cove, Greenwich, Longueville.
Upper North Shore: Roseville, Lindfield, Killara, Gordon, Pymble, St Ives, Turramurra, Warrawee, Wahroonga, Hornsby.
We’re a Sydney-wide business, so if your suburb isn’t on that list it’s still worth a call.
Council approval and trees on the North Shore
The North Shore spans six councils — North Sydney, Mosman, Willoughby, Lane Cove, Ku-ring-gai and Hornsby Shire — and while the state rules are the same everywhere, the tree and heritage controls are not.
When you don’t need a DA. Under the NSW exempt development rules, a deck can usually go ahead without approval if it’s no more than 25m² in floor area, sits no more than 1m above ground level, and meets the setback and site-coverage limits. That covers a lot of small ground-level decks.
When you do. Go above 1m, past 25m², or into a heritage conservation area — and much of Mosman, Hunters Hill’s fringe, and pockets of Willoughby and Ku-ring-gai are conservation-mapped — and you’re looking at a Complying Development Certificate or a full DA.
Trees. Every North Shore council protects trees over a threshold size, and works inside a tree protection zone (including footings) generally need consent. Ku-ring-gai is the strictest. We plan the footing layout around this rather than through it.
We’re not a planning consultancy, but we’ve been through this enough times to tell you which category your job falls into before you spend money on drawings.
Pool decks and pool barrier rules
A lot of North Shore pools sit in tight, sloping side yards, and the deck has to work with the fence rather than against it.
Under the NSW pool rules a barrier has to be at least 1.2m high with a 900mm non-climbable zone, and a deck built too close to a fence can turn it into a climbable object — which fails an inspection even if the fence itself is fine. We set the deck level and the fence line together so the finished job passes.
We also handle stepped pool surrounds, spa integration and under-deck drainage so water goes where it should.
What a North Shore deck costs.
Wondering what decking costs per m²? The table below shows indicative installed prices per square metre for the materials we build with most in Sydney, on a level site with a finished deck height under 500mm. Use it as a starting point, then run your own numbers through our deck cost calculator.
-
Treated pine $915 - $965
-
Merbau $929 - $1,022
-
Australian hardwood (spotted gum, blackbutt, ironbark) $980 - $1,239
-
Trex Transcend (Tropicals / Lineage ) $1,017 - $1,199
-
Trex Select $950 - $1,199
-
TimberTech AZEK Prime+ $933 - $1,026
-
TimberTech AZEK Vintage $1,232 - $1,355
-
Millboard Enhanced $1,197 - $1,317
-
Woodevo Home WPC $905 - $995
-
Woodevo Advanced PVC $928 - $1,021
Prices are indicative Sydney installed rates for 2026 and include the subframe, piers, fixings, boards, under-deck oiling, deliveries, waste removal and a final clean — not just the boards. That’s why they sit above the $350–$500 per square metre quoted elsewhere, which is usually materials only, or supply-and-lay by an unlicensed installer. Sloping blocks, difficult access, elevated decks, stairs, balustrades and pergolas add to the rate, and a quote that’s $200/m² cheaper usually means those things come back later as variations. Every deck is measured on site — request a free consultation for a firm figure.
Deck Builders North Shore Sydney — What Sets Us Apart.
- The bloke who quotes your job builds your job. No sales rep, no subcontracted crew you’ve never met.
- 20 years of trade experience, company established 2017.
- 10-year workmanship warranty, with a project inspection at three months.
- Rated 4.8 on Google.
- Fully licensed builder — licence 238750C.
- We work across Sydney, so we’re not learning your council’s rules on your job.
North Shore decking FAQs
How much does a deck cost on the North Shore?
Installed rates run from $905/m² for Woodevo composite up to $1,355/m² for AZEK Vintage, with most timber decks landing between $915 and $1,239/m². Sloping and bush-backed North Shore blocks usually sit at the upper end of a given range because of deeper footings, more substructure and harder access. That price includes piers, substructure, attachments, under-deck oiling, boards, deliveries, waste removal and a final clean.
Do I need council approval for a deck on the North Shore?
Often not. Under the NSW exempt development rules a deck of 25m² or less, sitting no more than 1m above ground and meeting the setback limits, can generally be built without approval. Go higher, bigger, or into a heritage conservation area — common through Mosman, Willoughby and parts of Ku-ring-gai — and you'll need a Complying Development Certificate or a DA. We'll tell you which one your job falls into before you spend anything on drawings.
Can you build a deck on a steep block?
Yes — most of our North Shore work is on a fall. We build raised decks on engineered piers and posts with H4-treated substructure and stainless fixings, plus compliant balustrades and stairs down to the yard. The steeper the site, the more the structure under the deck matters.
My place backs onto bushland — what can I build with?
If your property is on bushfire-prone land, the deck has to meet a Bushfire Attack Level. Between BAL-12.5 and BAL-29 you're limited to fire-resistant timbers and approved composites. Above BAL-29 we use Knotwood aluminium decking, which is non-combustible and still looks like timber. We check the bushfire map for your address before quoting.
Will the trees on my block be a problem?
Not usually, but they do shape the design. Every North Shore council protects trees over a certain size, and excavating inside a tree protection zone — including for footings — generally needs consent. Ku-ring-gai is the strictest. We set out footings to work around root zones rather than through them.
Can you build a deck around my pool?
Yes, and we build it to work with the pool barrier rather than against it. NSW rules require a 1.2m barrier with a 900mm non-climbable zone, and a deck set at the wrong height next to a fence can fail an inspection by creating a climbable surface. We set the deck level and the fence line together, and handle stepped surrounds, spa integration and drainage.
How long does a North Shore deck take to build?
What warranty do you get?
A 10-year workmanship warranty on everything we build, on top of the manufacturer warranty on the boards. We come back for a project inspection at around three months and issue the formal warranty documentation then.
Also building nearby
The Eastern Suburbs run straight into the Inner West, and we build across both. Further out, we work the Sutherland Shire, Hunters Hill and the Hills District.