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TNV (Technical and Numeric Variation) SA Planning and Design Code

A TNV is a spatially mapped numeric variation in SA's Planning and Design Code, overriding zone defaults for setbacks, heights, or frontage lot by lot.

By Dan Waring. Last updated 11 June 2026. Verified 11 June 2026.

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A Technical and Numeric Variation (TNV) is a spatially mapped adjustment to a quantitative standard in South Australia’s Planning and Design Code. Where a TNV applies to a lot, it overrides the zone’s default number for that specific mapped area. The zone stays the same; only the numeric parameter changes.

Note: TNV is unrelated to TMV (Thermostatic Mixing Valve), a plumbing term. The three-letter similarity causes confusion when searching; confirm you are on the planning code definition, not the plumbing one.

What TNVs vary:

TNVs are used to calibrate numeric parameters that differ across local council areas, including:

  • minimum allotment (lot) size
  • minimum frontage width
  • front, side, and rear setbacks
  • building height (in metres or number of storeys)
  • site coverage percentage

Why TNVs exist:

When SA replaced 72 separate council Development Plans with a single state-wide Code on 19 March 2021, it needed a mechanism to preserve council-level numeric diversity without fracturing the Code. TNVs do that job. The zone provisions set the state-wide starting point; the TNV layer records where a council’s historic controls differed from that baseline. Two lots in the same zone in different councils may have different TNV-set frontage or setback requirements (verified 2026-05-23, plan.sa.gov.au).

Where to find the TNV for a lot:

Open the PlanSA portal at code.plan.sa.gov.au and search by property address. The property report shows the zone, subzones, overlays, and any TNVs that apply, all on a single screen. Check this before quoting or drawing anything; assuming the zone default applies without checking for a TNV is a common cause of non-compliant designs.

Builder takeaway:

Always pull the PlanSA property report as the first step on any SA job. If a TNV applies, use the TNV value, not the zone default. Missing a TNV typically means the setback or height in your drawings is wrong before a line is drawn on site.

Also known as: Technical and Numeric Variation; SA Code TNV layer.

Category: Planning / South Australia.

See also

References

  • SA Planning and Design Code (Version 2026.1), via plan.sa.gov.au (verified 2026-05-23).
  • Planning, Development and Infrastructure Act 2016 (SA), via SA Law Handbook (verified 2026-05-23).

Last updated: 2026-06-11. Verified: 2026-06-11. Quarterly review for currency.

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