What the regulations require
The building regulations (OIB Guideline 3, edition 2023) give no air flow rates and do not require a ventilation concept. For the design, they refer to ÖNORM H 6038. The plan Aira makes is therefore a recommendation, not a legal minimum.
The recommended values
Aira uses these values from ÖNORM H 6038:2014. The air change is at least 0.5 per hour, and 0.3 per hour for a dwelling above 150 m². The design flow is the higher of the air change and 36 m³/h per person.
| Room | Extract (m³/h) |
|---|---|
| Kitchen | 40 |
| Bathroom with toilet | 40 |
| Separate toilet | 20 |
| Storage room | 10 |
Worked example
A home of 100 m² with a ceiling height of 2.5 m, which is 250 m³, and three people. Air change: 0.5 × 250 = 125 m³/h. Persons: 3 × 36 = 108 m³/h. The design flow is the higher value, 125 m³/h.
How Aira applies it
Aira assumes a ceiling height of 2.5 m, because a plan shows no volume. The number of persons follows the bed spaces: two in the largest bedroom and one in each other bedroom, which you can change in the table. A storage room of 10 m² or more gets the extract of 10 m³/h; a utility room gets no extract point.
Source
ÖNORM H 6038 is sold by the standards publisher and is not available free of charge. The values come from published descriptions and may be from an older edition. Aira offers the country as a closed beta, and the full standard should be checked before these values are used as a requirement.
- OIB-Richtlinie 3 (2023) and ÖNORM H 6038