One resolves a level change; the other needs the ground to already be close to level.
A deck is a structure raised on a substructure of bearers, joists and footings; a patio is a paved surface built up from prepared, compacted ground. That difference is the whole story: a deck can span over an awkward drop from the house without earthworks, while a patio needs the ground beneath it to already be close to the finished level — or needs fill and retaining to get it there first.
Once the level change from the house to the garden is known, most of the deck-versus-patio decision falls out automatically. What is left after that is a genuine comparison of maintenance, cost per square metre and how each surface handles water — which is what the rest of this guide works through.
01 · Compare directly
Deck and patio, side by side.
Assuming a mid-range timber deck and a mid-range paved patio, both correctly built.
Timber deck
Handles a level change?Yes — this is its main structural advantage over a patio
Underfoot in summerTimber stays cooler underfoot than dark pavers in direct sun
Maintenance cyclePeriodic oiling or staining, typically every 1–3 years depending on exposure and timber type
Water beneath the surfaceGapped boards shed water through to the ground below, which needs its own drainage path
Paved patio
Handles a level change?No — needs the ground close to finished level already, or fill/retaining first
Underfoot in summerCan get noticeably hot on darker pavers in full sun exposure
Maintenance cycleOccasional resealing or joint maintenance; otherwise largely maintenance-free
Water beneath the surfaceFalls are built into the base so water sheds across the surface to a defined point, not through it
02 · What else should move the decision
Beyond level change, four practical factors.
Height above ground
A deck more than a modest height above finished ground level typically triggers a building code balustrade requirement, which adds cost and changes the design.
Substructure ventilation
Timber decks need airflow beneath the boards to avoid trapped moisture; low-clearance decks close to the ground are more prone to substructure decay.
Drainage away from the house
A patio's falls have to be built correctly away from the building; getting this wrong sends water toward the foundation instead of away from it.
Long-term flexibility
A deck substructure is easier to adapt later — extending, adding steps, changing the balustrade — than breaking out and re-laying a paved patio.
03 · Two worked examples
Two houses, two different answers.
Rear living area 900mm above the garden
That drop rules a ground-level patio out on its own — filling and retaining to close a 900mm gap would cost more than the surface itself. A timber deck with an engineered substructure and a code-compliant balustrade is the direct answer.
Slab-on-ground home with a flat rear yard
Minimal level change means either option is structurally possible, so the decision shifts to maintenance appetite and underfoot comfort. A paved patio with correctly detailed falls away from the slab is usually the lower-maintenance choice here.
04 · Before comparing quotes
Make sure quotes are actually comparable.
- Measure the real level change from the internal floor to the finished garden level, not an estimate.
- Confirm whether the deck height triggers a balustrade requirement — ask the quote to state this explicitly.
- Ask what base preparation a patio quote includes, not just the paving material.
- Check how each option sheds water away from the house before finalising the choice.
Deck vs. patio: common questions
Can a patio be built on a moderate slope with some fill?
Yes, for modest level changes — but once fill depth becomes significant, retaining is usually needed to hold it, which adds a structural element and cost that a deck avoids entirely.
Is composite decking a genuine alternative to both?
Composite is a decking material choice, not a structural alternative — it still needs the same substructure as timber decking, just with a different, lower-maintenance surface on top.
Which one adds more resale value?
Neither has a fixed answer nationally; a well-built, well-integrated surface that suits the house and site tends to add more perceived value than the material choice itself.
Do decks need a consent?
It depends on height above ground and other factors set by the building code — confirm with your council or a licensed building practitioner before assuming either way.
Sources & methodology
Designed to show its working.
Deck height, balustrade and consent requirements vary by council and site. This guide is general comparison guidance; confirm structural and consent requirements for the specific property with a licensed building practitioner.