A weather louvre is a passive device, essentially a grille fixed over an opening, designed to let air through and keep water out. It is designed to the same standard as our other high integrity dampers and performs both these functions simultaneously. Its suitability for a particular application is determined by how effectively it achieves these functions in combination.
Failure to understand and clearly express the performance requirement at the design or procurement stage increases the risk of the product not being fit for purpose. The end user may experience unwanted water penetration or wasted energy.