I have ventilation grilles in a room on a brick wall, there are 4, two at the top and two at the bottom on both sides of the wall, sometimes there are smells a little unpleasant coming out. What is the solution to remedy this problem?
Ideally, if you want to stay on static ventilation, you should create a ventilation scheme for the whole house. You do not need four openings in the same room. Instead, place the grates so that the air enters the dry rooms (living room, bedrooms, etc...) and so in humid places (bathroom, kitchen, WC). Entrance grates should be positioned at the top of the windows and the outlet grilles located on the ceiling, ideally with a roof outlet for more efficiency. For the proper functioning of this type of ventilation remember to leave one day under the doors of 1.5 cm.
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