In brief

• The costs of electricity increased by 16.1 percent in August compared to July and were 20.5 percent higher compared to August 2024.
• The cost of diesel oil increased by 3.2 percent in August compared to July and were 6.2 percent lower compared to August 2024.
• Interest costs decreased by 21.2 percent between August 2024 and August 2025.
• Construction clients’ costs decreased by 8.8 percent in August 2025 compared to August 2024.

Changes in the last month

The Construction Cost Index for multi-dwelling buildings increased by 0.4 percent between July 2025 and August 2025. This increase was due to the fact that contractors’ costs increased by 0.5 percent. Construction clients’ costs decreased by 0.1 percent. These two groups account for 18 percent and 82 percent, respectively, of the Construction Cost Index.

Costs in the group ‘transport, fuel and electricity’ increased by 3.4 percent. Within that group, the cost of electricity and the cost of diesel oil increased by 16.1 and 3.2 percent respectively. The cost of transport increased by 0.5 percent. Contractors’ overhead costs rose by 0.2 percent while costs for machinery fell by 0.4 percent. The costs for wages and salaries remained unchanged.

Contractors’ costs for building materials rose by 0.6 percent in August 2025. Among the building material groups, the cost of electric material and plumbing material rose by 2.8 and 1.3 percent respectively. The cost of concrete products and wood products fell by 0.2 and 0.1 percent respectively. The remaining material costs were unchanged or rose up to 1.0 percent between July and August 2025.

Construction clients’ costs decreased by 0.1 percent in August. Construction clients’ costs consist of interest and credit costs, costs for plans, and central administration. The decrease in construction clients’ costs was due to lower interest costs which fell by 0.4 percent.

Changes in the last year

The Construction Cost Index for multi-dwelling buildings decreased by 0.2 percent between August 2024 and August 2025. Contractors’ costs rose by 2.3 percent, which led to an upward contribution to the Construction Cost Index of 1.8 percentage points. Construction clients’ costs decreased by 8.8 percent, which led to a downward contribution to the Construction Cost Index of 2.0 percentage points. The decreased construction clients’ costs was due to lower interest costs, which decreased by 21.2 percent. The remaining construction clients’ costs increased by between 1.1 percent and 3.7 percent.

Contractors’ costs for wages and salaries and overhead costs increased by 3.5 percent and 2.8 percent respectively, while costs for machinery decreased by 0.8 percent between August 2024 and August 2025. Contractors’ costs in the group ‘transport, fuel and electricity’ increased by 2.7 percent. Within that group, the cost of diesel oil decreased by 6.2 percent while electricity increased by 20.5 percent. The costs for transport fell by 0.1 percent.

Contractors’ costs of building materials increased by 1.9 percent between August 2024 and August 2025. All costs in the building material groups rose except for the cost of electric materials, which decreased. The costs of wood products and materials for painting increased the most, by 9.7 percent and 10.8 percent respectively.