Why is it important to ventilate?
Ventilation is necessary to provide a healthy and comfortable internal living environment. The main goal of ventilation is to replace polluted indoor air with fresh outdoor air through purpose-provided openings.
The Approved Document Part F (means of ventilation) of the Building Regulations for England and Wales recommends the following three-pronged strategies.
- Extract ventilation – From rooms where most water vapour and other pollutants are released, e.g. kitchens and bathrooms (commonly known as wet rooms).
- Whole dwelling/building ventilation – is intended to provide fresh air to the dwelling, diluting and dispersing water vapour and pollutants.
- Purge ventilation – throughout the dwelling to aid in removing high levels of pollutants and water vapour. Purge ventilation is intermittent, for example, opening a bathroom window after bathing. Purge ventilation may also be used to improve thermal comfort. The drawback to this ventilation method is that the air can be too hot or cold or polluted depending on the season.
Mechanical Ventilation with Heat Recovery (MVHR) (previously known as System 4)
The benefit of installing an MVHR system is that the incoming air is filtered before passing through a heat exchanger, which recovers heat from the stale outgoing air before being delivered to habitable rooms within the dwelling.
