Finnish Guidelines of Ventilation Rates for Non-residential Buildings

Abstract

The new Finnish Decree on the Indoor Climate and Ventilation of New Buildings 1009/2017 [1] is part of the implementation of Energy Performance of Buildings Directive in the EU. The new Decree specifies the minimum design ventilation rate to be 6 dm3/s, person (outdoor air). The Decree also specifies that the ventilation shall be controlled by demand when feasible. These requirements in the Decree were considered to be too plain and inadequate for practical design. FINVAC carried out an investigation [2,3] regarding the experience on the old ventilation regulation [4]. Based on the result of these investigations new guidelines were prepared and published in 2018. Majority of the experts considered 6 dm3/s, person as an appropriate value of the minimum ventilation rate. The investigations revealed that in many cases the old recommended values (dm3/s, m2) were either too high or too low. This has led to poor air quality in some cases and excess energy use in some cases. Too high ventilation rates were used for corridors, restaurants, cafeterias, supermarkets, department stores, shops, hotel rooms, auditoriums, halls, and washing rooms. The total air flow was also too high for day care centres, and for some apartments. Too low ventilation rates were given for elderly homes, classrooms, fitness centres, sports halls, residential kitchen hoods, operation rooms in hospitals, and for some apartments. Detailed guidelines were prepared and structured by building type (offices, schools, hospitals, elderly homes, restaurants, hotels, stores, sports facilities, barracks, theatres, industrial working places, kitchens, spaces for personal hygiene and technical rooms). Separate guidelines were prepared for residential buildings [5]. Both guidelines were published in the beginning of the year 2018.