Construction Cost Index Australia: Which ABS Measure Should You Use?

Short answer

Australia does not have one construction cost index that answers every building-cost question.

For detached-house materials, the ABS Input to the House construction industry index is the closest fit. For prices received by builders for house construction, use the Output of House construction index. For inflation experienced by households buying new dwellings, the CPI new-dwellings series has a different purpose and scope.

None of these measures is a substitute for a current quote, quantity-surveyor estimate or contract review.

The June quarter 2026 construction price update shows how the measures can move by different amounts in the same period.

The main measures compared

Start with the question being asked. A materials index is not a complete build cost. A new-dwelling CPI series is not a house-price index. A national movement is not a regional tender price.

Input to house construction

The ABS input index tracks products used in detached-house construction. Its conceptual price is the purchaser's price, including relevant transport and trade margins, with products ideally priced as delivered on site.

The index is useful when the question concerns the movement of building materials such as timber, metal products, electrical equipment and plaster products.

It does not explicitly cover:

• builder labour;
• alterations and additions;
• renovations and repairs;
• residential land;
• apartment construction; or
• the complete price paid by a client for a finished house.

Calling it a complete construction cost index can therefore overstate what it measures.

Output of house construction

The output index measures prices received by producers for house construction. The ABS scope includes house construction for owner-occupiers and investors.

It is broader than the materials-only input index, but it remains an industry price measure. It cannot account for every site's earthworks, access, engineering, planning conditions, finish level, builder capacity or contract allocation of risk.

For apartments and other attached residential work, the ABS publishes an Other residential building construction output index. Use the dwelling type that matches the question rather than applying detached-house movements to a large apartment project.

CPI new dwellings is different

Australia's CPI measures inflation experienced by households. Its new-dwellings component uses a net-acquisitions approach for new owner-occupied housing. It excludes land and established dwelling transfers between households.

The ABS says this measure captures construction costs including materials, labour and builder margins. Government grants and subsidies are treated differently from the producer output index, so the CPI and PPI series need not move together.

The CPI new-dwellings series is useful for economy-wide household inflation analysis. It does not show:

• the market value of an established home;
• the repayment on a mortgage;
• the cost of residential land; or
• a person's likely renovation or build cost.

Use the Inflation Calculator only after choosing and entering an assumption that fits the question. The calculator compounds the rate entered; it does not select an official construction series or predict future prices.

Worked example using index numbers

An index can update a historical amount for a broad comparison. The standard calculation is:

Updated amount = old amount x new index / old index

The national input to house construction index rose from 164.3 in March 2026 to 167.8 in June 2026.

For a historical materials allowance of $400,000:

$400,000 x 167.8 / 164.3 = about $408,521

The implied movement is about 2.13%, which rounds to the ABS published quarterly change of 2.1%.

This result is an index-only illustration. It does not mean a $400,000 contract became $408,521, and it does not establish a valid contract variation. The historical amount may include labour, margin, land, finance, professional fees or work outside the index.

How to choose an index

Use this sequence:

1. Define the cost being compared: materials, builder output, household inflation or a project quote.
2. Match the dwelling type: detached house, attached residential or non-residential.
3. Match the geography: national, state or sampled capital city.
4. Match the dates and index series exactly.
5. Record whether the index includes tax, transport, labour, margins, land and subsidies.
6. Treat the result as a broad comparison unless the contract or professional instruction specifies that index.

If a contract contains an indexation clause, use the exact series, reference period and calculation method stated in the contract. Do not substitute a different ABS series because its latest percentage looks more favourable.

Geography and timing matter

The June 2026 release illustrates the spread. Quarterly house construction output prices rose 0.7% in Victoria and 4.7% in Tasmania. A national 2.0% movement hides that range.

The input index publishes sampled capital-city results but does not sample territory prices. The output house construction tables publish state and territory results. Read the table label before describing a number as national, state or city data.

Indexes also have reference periods. Applying a June-quarter annual rate to a budget dated part-way through the year can create a mismatched comparison.

Common mistakes

• Using headline CPI as a construction-cost forecast.
• Treating materials inflation as a complete building price.
• Applying a detached-house series to an apartment project.
• Assuming a national result applies to every state and region.
• Adding an index movement to land value.
• Ignoring the date and scope of the original estimate.
• Treating an index calculation as authority to vary a contract.
• Combining several overlapping indexes and counting the same price movement twice.

For a contract with uncertain allowances, read Provisional Sums in Building Contracts. The Property Purchase Cost Calculator covers purchase transaction costs, not construction estimates or contract variations.

Sources

• Australian Bureau of Statistics: Producer Price Indexes, Australia, June 2026, released 31 July 2026 and checked 1 August 2026.
• Australian Bureau of Statistics: Producer Price Indexes methodology, June 2026, including construction index scope, valuation and weighting. Checked 1 August 2026.
• Australian Bureau of Statistics: Consumer Price Index Concepts, Sources and Methods, 2025, released 26 November 2025 and checked 1 August 2026.
• Australian Bureau of Statistics: Measuring owner-occupied housing in the Consumer Price Index, released 30 October 2024 and checked 1 August 2026.

General information disclaimer

This guide provides general information only. It is not financial, building, engineering, legal, quantity-surveying or contract advice. An index result is not a quote, valuation, forecast or determination of contractual rights. Check the exact series, project scope and contract with appropriately qualified professionals before relying on an indexed amount.

Last updated: 1 August 2026.