The four building groups

Statistics Estonia methodology includes four groups of buildings in the calculation, whose cost structures are not the same. Each group has its own cost structure.

Building group	Characteristic cost structure
Houses	larger structural share, smaller services share
Apartment buildings	repetition lowers unit cost
Industrial buildings	large spans, simpler finishes
Office buildings	largest services share

Because the cost structures differ, so do their price movements. The group indices diverge quarter by quarter.

Three reasons. The shares of materials and labour differ by building type. A labour intensive building responds more strongly to wage growth, which was the main driver in the first quarter of 2026.

The share of building services differs. It is larger in an office building than in a house.

Structural solutions differ, which ties different building types to different materials.

Practical consequence: applying the house index to an office building, or the reverse, transfers a cost structure that is not the same. The indicator for the relevant group must be used.

This is the most important point in the article and it is rarely noticed. The group is chosen before the calculation.

For the repair and reconstruction price index the buildings under observation are office buildings.

This means the repair index is built on office buildings, not dwellings. To assess the price movement of renovating a flat or a house, an indicator compiled for a different building type is therefore being used.

Index	What it is built on	What it is often used for
Construction price index	four building groups	new build
Repair and reconstruction index	office buildings	renovation of flats and houses

This does not make the index useless, but it must be stated when the index is used in that context. Renovation cost questions are covered in a separate guide, and this article is limited to the methodological limitation.

Three steps. Determine the building type before choosing the index.

Check whether this is new build or repair and reconstruction, because these are different indicators. They are separate indicators.

State which indicator was used, where the index appears in a document or a contract. An unnamed indicator cannot be checked.

The third step is mandatory in a contractual context, because without it an indexation clause is not unambiguous and, in a dispute, it is unclear what the parties agreed. The dispute then turns on the basis of the calculation.

Two things the group split does not cover. Regional differences. The index is a national indicator.

The particularities of a specific project, for instance complex architecture or difficult access. The index describes the market, not the project.

These two can weigh more than the movement of the index as a whole on a single project. A project on a difficult access plot can cost substantially more than the same project on an ordinary plot, and no index describes that difference.

The construction price index includes four building groups whose cost structures, and therefore price movements, are not the same. For the repair and reconstruction index the buildings observed are office buildings, so assessing the renovation of a dwelling uses an indicator compiled for a different building type. The index does not distinguish regional differences or project particularities, which can weigh more than its movement.

Four rules: choose the indicator by building type, do not use the headline figure by default. Distinguish the new build and repair indices. State the limitation of the repair index when using it for dwellings. Name the indicator used precisely in a contract.