Brief definition
HOAI governs fees for architectural and engineering services. DIN 276 structures construction costs into cost groups. In early design, both systems are used in parallel — cost groups support cost estimating; HOAI governs remuneration for planning services.
Practice
- Early phases: rough cost-group estimates from areas and building construction
- Detailed design: detailed BoQ quantities per cost group
- Alignment of fee band vs. actual planning effort remains separate
Normraum relevance
In the early service phases, cost estimates are built from areas. Normraum supplies them from the as-built plan: area per room under DIN 277 in the room book, with confidence score and source reference in the check log. Fee band, service phases and the assignment to cost groups stay in the planning – Normraum replaces neither the HOAI logic nor the survey.