How to Reduce Odours in Commercial Buildings With the Right Filtration

Odour complaints in commercial buildings usually come down to air movement, source control and the condition of the filtration system. Food courts, basements, plant rooms and shared amenity areas can all move unwanted smells into places people notice quickly, especially when ventilation is not balanced or filters are not suited to the space.

For facility managers, property managers and hotel operators, the goal is not just to mask smells. It is to capture the airborne particles and compounds that travel through the building, improve the way air is moved, and match the filter type to the odour source and system design.

Why odours spread through commercial buildings

Odours often travel farther than expected because they follow the air paths already built into the property. If a system is drawing air from a smell source, recirculating it through shared ducts, or using filtration that is too coarse for the situation, the odour can migrate into lobbies, corridors, lifts, guest areas and workspaces.

Common contributing factors include:

• •Exhaust systems that are underperforming or out of balance
• •Dirty or loaded filters creating resistance and reducing airflow
• •Poor separation between odour sources and return air points
• •Grease, dust and fine particles carrying smell through the system
• •Basement spaces with limited fresh air and persistent moisture or mould odours

A good approach starts with the source. If an odour is being generated by food preparation, waste storage, damp materials or maintenance activities, filtration can help, but it needs to be paired with suitable ventilation and housekeeping.

Food court and kitchen-adjacent odours

Food courts are one of the most challenging areas in a mixed-use building because the air can contain grease, smoke by-products, steam, fine particles and cooking odours all at once. The filtration strategy needs to suit both the supply air and the exhaust or recirculation path.

What to look at first

• •Check whether odours are entering from nearby tenancies, kitchen exhausts or shared return air pathways
• •Confirm that pre-filters are capturing larger dust and grease-laden particles before they reach finer filters
• •Inspect housings, seals and filter frames for bypass, which can let odour-carrying air around the filter media
• •Review whether the system can accommodate activated carbon or other gas-phase media where appropriate

In these spaces, particle filters alone may not be enough if the main complaint is smell rather than visible dust. Activated carbon filters can help adsorb certain airborne odorous compounds, but they need to be selected for the specific application and replaced according to the manufacturer’s instructions and the site’s loading conditions.

For buildings that use custom filter sizes or unusual housings, custom air filters can help keep the system sealed properly and reduce the risk of bypass.

Basement odours and low-level air quality issues

Basements often develop stale, earthy or damp odours because air turnover is limited and moisture tends to linger. If there is dust, debris or mould growth in hidden areas, the smell can become noticeable in lifts, back-of-house zones and ground-floor entry points.

A practical filtration plan for basement areas should focus on both incoming and exhausted air:

• •Use suitable pre-filtration to stop dust from loading up downstream filters too quickly
• •Check for damp insulation, wet flooring, blocked drains or standing water, as filtration alone will not fix a moisture source
• •Consider whether odour adsorbing media are needed in recirculated air paths
• •Make sure access panels, fan housings and ductwork are clean and intact

If the basement forms part of a larger mechanical system, the mechanical services engineer or building owner should confirm the site requirements in line with AS 1668.2:2024. The right filter selection depends on how the system is designed to move and condition air, not just on the smell itself.

Amenity areas, toilets and shared spaces

Amenity spaces can create odour issues even when they are clean, especially where airflow is weak or pressure relationships allow smells to spread beyond the room. Toilet areas, locker rooms, end-of-trip facilities and staff break areas often need careful attention to extraction and filtration.

Filtration strategies that can help

• •Maintain a staged filtration setup where the system design allows it
• •Use finer filters where airborne particles are contributing to lingering odours
• •Check for fan issues, damaged seals and poor airflow at return grilles
• •Review whether the space needs more local exhaust rather than relying on general building air movement

In hotels and mixed-use properties, guest comfort can be affected by odours that move from amenity spaces into corridors or reception areas. The best result usually comes from combining good source extraction, clean ductwork and the right filter media for the application.

Some filters are designed to be washable - check the product instructions before assuming a filter can be cleaned and reused.

Choosing the right filter media for odour control

Not every odour problem needs the same kind of filter. In commercial buildings, the right choice often depends on whether you are dealing with particles, grease, moisture, or gaseous odours.

Useful filter types can include:

• •Coarse pre-filters for larger dust and lint
• •Medium-efficiency filters for finer particulate loading
• •Activated carbon filters for certain odorous gases and vapours
• •Combined systems where particle filters protect and extend the life of downstream odour media

If you are comparing ratings, it helps to remember that MERV, EN 779 and ISO 16890 do not convert directly. EN 779 classes such as G3/G4/F5-F9 are still widely used in Australia, even though ISO 16890 has superseded EN 779. For higher-efficiency applications, HEPA filters may be considered where the system is designed for them. H13 filters are at least 99.95% efficient and H14 filters are at least 99.995% efficient at the most penetrating particle size under EN 1822.

That said, a higher rating is not automatically better for odour control. If the filter is too restrictive for the fan or the housing, airflow can suffer and odours may become more noticeable rather than less. The system has to be matched as a whole.

You can explore our products to see the types of filters commonly used in commercial systems.

Keeping odour control effective over time

Even a well-selected filter will only perform as intended if the system is monitored and maintained. Odour complaints often increase when filters become loaded, damaged or poorly seated.

A good maintenance approach includes:

• •Inspecting filters based on the system, the site conditions and the dust load
• •Following the filter and equipment manufacturer instructions
• •Monitoring pressure drop where gauges are fitted
• •Checking for damaged gaskets, bent frames or poor installation fit
• •Reviewing upstream dirt sources if filters are loading too quickly

If a building keeps developing the same smell in one area, the issue may be as much about airflow and maintenance access as about the filter itself. In some cases, filter servicing or commercial filter servicing can help keep the system operating as intended.

Getting the right filtration setup for your building

Odour control in commercial buildings works best when the filtration plan is tailored to the site. A food court, basement plant room and hotel amenity area all need different solutions, even if the complaint is the same: the smell is spreading.

Total Air Filtration is a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, and we can help with the right filter selection or a custom-made solution for your system. Call 07 3800 3448 or request a quote.

If you are unsure what size or style you need, start with how to measure an air filter or contact us to discuss the site requirements.