Ventilation in a new house – what are the options?

Ventilation in a new house – possible solutions

When planning the construction of a new house, you must be sure to take care of proper ventilation. Mechanical ventilation with heat recovery may prove essential. Contrary to popular opinion, this is not such a costly solution; in the long term it will allow you to optimise the installation of ventilation ducts, which will be not only shorter but also cheaper and will not offer too much resistance to the flowing air. Mechanical ventilation is treated as an alternative to traditional gravity ventilation.

Traditional gravity ventilation

You can often come across the opinion that traditional gravity ventilation is a cheap and effective solution and that no changes are needed here. On the other hand, it should be remembered that using this option requires solid foundations for the ventilation chimneys, purchasing the right material and building it in. Sheet-metal work on the roof of the house and subsequent maintenance of the chimneys are also necessary. Moreover, the operation of gravity ventilation means continuous heat losses as a result of the need to heat fresh, cold air. It is sometimes estimated that these losses amount to as much as half of the heating costs!

Mechanical ventilation with heat recovery

The above solution is increasingly used by prudent users who decide on a long-term reduction of the costs of heat losses in their homes. Mechanical ventilation with heat recovery is calculated for purely economic reasons as a substitute for traditional gravity ventilation. Already at the house-design stage, such a change is postulated in order to be able to optimise heating costs more effectively.

Although for many centuries people did not use mechanical ventilation, it is nowadays a solution that is increasingly recommended and, above all, actually implemented by people building houses. Gravity ventilation is becoming less and less efficient in times when people have started using increasingly airtight door and window joinery. The balance between the air that has left the rooms and the air that has entered them from outside is disturbed under these conditions, which weakens the efficiency of gravity ventilation. For this reason, people decide to make windows less airtight or to install special wall air inlets, but this is a solution that only partially solves the described problem. It is difficult to control the amount of ventilation air – gravity ventilation then works too intensively during frosts and almost not at all during heatwaves. There is also the problem of uneven ventilation – an example is too little ventilation of the house's attic due to ventilation ducts that are too short, while the ground floor is over-ventilated.

Improper ventilation results in too much water vapour, carbon dioxide, allergens or even dust in the house. The concept of the so-called "sick building syndrome" is sometimes cited here as a result of improper house ventilation. Therefore, a way to counteract this phenomenon is to use mechanical ventilation with heat recovery. Heat is recovered from the air removed from the rooms, which is referred to as heat recuperation, treated as a highly economical solution when designing ventilation in a new house.