Guide to Choosing the Right Ventilation Grille Based on the Space

There's no universal grille. A grille well-chosen for a bedroom can be a poor solution for an industrial kitchen or a shared garage; a grille designed for an industrial building can be disproportionate and poorly integrated into a home's facade. This guide reviews the most relevant selection criteria and proposes concrete solutions for each type of space, with references to the Spanish Building Code (CTE DB-HS 3) and the made-to-measure manufacturing of the Industrias Mas team.

Before requesting a quote, it's worth having five factors clear. 1) Function: whether the grille acts as fresh air intake or stale air outlet; this changes the recommended location and sometimes the louver geometry. 2) Physical location: exterior wall, interior wall, false ceiling, raised floor; each has its own fixing system. 3) Minimum flow rate: set by CTE DB-HS 3 based on the type and surface area of the space. 4) Environmental conditions: humidity, salinity, temperature, presence of greasy vapors or chemical agents. 5) Aesthetic requirements: RAL color, integration with window frames, visibility of fixings.

In housing, CTE DB-HS 3 sets minimum flow rates that differ by room. Bedrooms and living rooms ('dry' rooms) receive fresh air; kitchens and bathrooms ('wet' rooms) extract stale air. Facade grilles are typically used for air intake from outside, complemented by mechanical extraction or indoor air transfer to complete the path. For this application, powder-coated aluminum is practically the only reasonable material: lightweight, weather-resistant, matchable to any window frame color, and maintenance-free afterward. Industrias Mas keeps five standard colors in stock: black (RAL 9005), anthracite (RAL 7016), dark grey (RAL 7022), natural (RAL 9006), and white (RAL 9003).

Kitchens and bathrooms are the spaces with the highest extraction requirements in housing. The grille is usually paired with a mechanical extractor that ensures air renewal even when there's no wind. Powder-coated aluminum remains the suitable material for the facade grille (it withstands ambient humidity perfectly), but the indoor ducting may be a different material depending on the system. In industrial and professional kitchens with intense greasy vapors, AISI 304 stainless steel is worth considering for parts in direct contact with the extracted air.

Offices and commercial premises usually combine passive facade ventilation with mechanical HVAC systems. Exterior facade grilles are chosen primarily for aesthetic integration: RAL color matching the window frames, concealed fixing, dimensions aligned with architectural modules. For retail and restaurants with storefronts and high visual requirements, a made-to-measure grille in a specific RAL makes the difference over a standard grille. Industrias Mas's powder-coated aluminum is delivered in any color from the RAL chart on request with no relevant lead-time penalty.

In industrial buildings the critical factor is free passage area. The volumes of air to be renewed are much larger than in residential settings, and the grille must be designed to let high flow rates pass without generating excessive pressure loss. The usual solution is large-format grilles (1000×1000 mm or larger) in powder-coated aluminum, with louvers sized to maximize airflow. Powder-coated aluminum keeps its advantage over galvanized sheet metal in this use too: greater durability with no periodic painting, reduced weight for high-level installation, and better aesthetic integration in buildings with exposed facades.

Garages and storage rooms have specific requirements: garages need to avoid carbon monoxide build-up and moisture from cars entering wet; storage rooms mainly need to manage ambient humidity. The grille must have sufficient free passage area and, in shared garages, is usually combined with permanent mechanical extraction or CO-sensor-triggered extraction. Powder-coated aluminum withstands a typical garage environment (humidity, dust, thermal cycles) with no issue.

Boiler rooms and technical plant rooms have specific ventilation regulations, both for proper combustion and for gas evacuation. The grille must be sized based on the installed appliance (nominal thermal output and fuel type). In natural gas or diesel installations, the usual grilles are large-format powder-coated aluminum, calculated to guarantee combustion air with no obstruction.

For housing and offices, powder-coated aluminum in a RAL integrated with the facade — sized to the opening. For industrial kitchens and food processing plants, stainless steel where there's contact with greasy vapors or hygiene requirements; powder-coated aluminum for the exterior facade piece. For industrial buildings and garages, large-format powder-coated aluminum with sufficient free passage area. Industrias Mas advises on correct sizing based on the project's drawings. Every grille is made to measure, in five standard RAL colors and any other color on request, delivered on-site across Spain.