Optimal ventilation? - Build 180(2020)
- Optimal ventilation?
- Valid from
- Information provider
- BRANZ Limited
- Information type
- BUILD article
- Website, PDF
Conventional ventilation keeps a home sufficiently aired but has an energy cost. An option is to install a mechanical ventilation heat recovery system that ventilates a home while efficiently conserving energy.
In New Zealand homes, New Zealand Building Code clause G4 Ventilation specifies that adequate ventilation is required to be provided through a combination of natural means – with windows and openings – and mechanical ventilation. The most common pathway for compliance with G4 is natural ventilation, with supplementary extract ventilation in bathrooms, for example.
This article includes:
- Opening windows does the job
- Mechanical ventilation and heat recovery
- Case study in a 100 m² house
- Efficiency and airflow balance
- Optimise ducting length and insulation
- Homes often spot heated
- Spot heating causes efficiency to drop
- Getting the highest efficiency