White plastic ventilation grilles with insect filter against a plaster wall

Which way should a ventilation grille be installed?

Ventilation of a house is essential to prevent moisture problems in your home, but also to maintain healthy indoor air. Indeed, indoor air tends to accumulate polluting particles, such as CO2, paint fumes or household chemicals. It is therefore necessary to constantly renew the air to avoid health problems such as asthma or allergies.

It is surprising, but indoor air is often more polluted than outdoor air. Therefore, the design of the ventilation system must include appropriate air inlets and outlets. To achieve proper ventilation in your home, a controlled mechanical ventilation (VMC) is mandatory for some rooms and ventilation grilles allow for optimal air circulation in other rooms.

What is a ventilation grille?

The ventilation grille is a perforated plate made of plastic, PVC or metal and usually equipped with a mosquito net to prevent insects from getting through. The locations in the dwelling are determined during the installation work.

A short parenthesis To find out more about DIY tips for the home, you can visit this siteBut let's get back to the point...

The grilles are placed in front of the air vents to allow air to enter (air inlet grilles) or exit (air outlet grilles) the house through the ventilation system or the natural air flow.

You can find ventilation grilles in round, square or rectangular shape and with a more or less elaborate design in PVC or metal. Depending on the room, you can choose a suitable grille. Some of them even have a noise reduction function. But a ventilation grille is not just an unimportant accessory...

Why are ventilation grilles important?

Grilles are very important as they can greatly improve the efficiency of your ventilation system. Installing a grille in the optimum location and in the right direction will help maintain a constant temperature and airflow. correct airflow, while saving energy. This requires good insulation of the house.

If the air vents are not used correctly (wrong location, wrong direction, insufficient number) the whole ventilation and heating system will be less efficient, which will have an impact on the natural ventilation of your home.

Stéphen Mure Architect | Natural ventilation

Where to install a ventilation grille?

The location of a ventilation grille The size of the air inlet/outlet can vary depending on the type of use and the room where it is to be installed. In order to install this air inlet/outlet in the best possible way, we have listed for you the main elements to take into account.

  • Air inlets The grilles that allow air to enter the home should be placed at the bottom of the walls or on the floor in each room. If natural ventilation is used, it is best to place them facing the prevailing winds to ensure better air circulation.
  • Extraction grilles Air outlets: In contrast, air outlets should be placed high up, and if possible on the sides opposite the prevailing winds.
  • In wet rooms In humid spaces such as bathrooms, kitchens and toilets, the installation of a ventilation system is mandatory. The exhaust grilles should be placed at the top (ceiling or top of the walls), as close as possible to sources of heat and humidity. (e.g. above the shower for the bathroom and above the cooker for the kitchen).
  • On the windows The use of grilles on windows is becoming less common, except on older windows. In this case you will have to drill the window to install a mortise and then the grille. This work is relatively easy to do for a good handyman.

Which way should the ventilation grille be installed?

All these clarifications were necessary, but now we come to the main subject of this article, the direction of the grid.

It may seem like a detail, but the orientation of a ventilation grille is important, as it plays a role in the efficiency of the entire ventilation system. Many do-it-yourselfers ignore this fact and make the mistake of placing the grille upside down... and this is detrimental to the whole infrastructure, even if all the rest of the work has been done perfectly... Some grilles should be placed high up on the extract units and others low down on the exhaust units...

When you install your ventilation grille, make sure that your installation follows the following direction:

  1. If you install a grille high up, it should face the ceiling.
  2. If you install your grille at the bottom, it should face the ground.
  3. What if you put it on the ceiling? It should be directed towards the main source of moisture creation. (e.g. the bathtub)

By following these simple guidelines, you can be sure that your grilles will be an effective part of the air intake and outlet of your ventilation system.