Choosing Filters for Strata Buildings: A Practical Guide

Choosing filters for a strata building is rarely just a matter of matching a size. The right choice depends on how the common-area system is used, what the building owner expects from indoor air quality, and how easy it is to access the equipment for servicing. A good filter selection process helps strata managers balance performance, maintenance practicality and building-specific requirements.

Start with the system, not just the filter size

Before selecting a replacement, identify exactly where the filter sits in the system and what it is protecting. Common areas in strata buildings can include lobby air handling units, corridor ventilation, car park exhaust systems, plant rooms and packaged rooftop equipment, and each may need a different approach.

Useful checks include:

• •the equipment make and model
• •the existing filter dimensions and frame type
• •the airflow direction through the cabinet
• •whether the filter is part of a pre-filter and main filter arrangement
• •whether the unit has room for deeper filters or only shallow cartridges or pads

It also helps to look at how the building is used day to day. A lobby with frequent foot traffic, doors opening to the street and nearby construction dust may need a different filter strategy to a low-traffic corridor or back-of-house ventilation system.

If you need help confirming a size or measuring an existing filter, see how to measure an air filter.

Consider resident expectations and building standards

Strata buildings often serve a broad mix of people, so filter selection needs to take expectations into account. Residents may notice visible dust, odour transfer, stale air or uneven airflow long before a maintenance issue becomes obvious.

It is useful to ask:

• •What spaces are connected to the system, and how visible is the air equipment to residents?
• •Are there known issues with odour from kitchens, car parks or refuse areas?
• •Has the building recently had refurbishment, waterproofing work or other dust-generating activity?
• •Is there concern about fine dust entering common areas during windy conditions or nearby works?

If the building has mechanical ventilation requirements, site needs should be confirmed with the mechanical services engineer or building owner, including any relevant expectations under AS 1668.2:2024. That standard may be relevant to ventilation design and operation, but the right filter choice still depends on the actual plant, the cabinet space and the way the system is run.

Where indoor air quality is a concern, filters can help capture particles from the air stream, but they are only one part of the building’s overall ventilation and maintenance approach. Residents with health concerns should seek medical advice.

Match filtration level to the job

Not every strata system needs the same filtration level. A filter that works well in one area may create unnecessary resistance in another, especially where airflow, fan capacity and dust loading are already challenging.

When comparing options, think about the purpose of each stage:

• •Pre-filters can help catch larger dust and debris before air reaches finer filters.
• •Main filters are chosen for the level of particle capture needed for the space and system.
• •Odour-related concerns may need a separate solution, depending on the source and system design.

In some buildings, a staged setup is useful because it can support better dust loading management and make routine servicing more practical. In others, there may be limited cabinet space, so the best option is the one that fits properly and can be maintained consistently.

Ratings can be useful reference points, but they should be interpreted carefully. MERV, EN 779 and ISO 16890 do not convert directly, so it is better to compare like with like rather than relying on a simple cross-reference. EN 779 classes such as G3, G4 and F5 to F9 are still commonly used in Australia, even though the standard has been superseded by ISO 16890.

For higher-efficiency applications, HEPA filters are a specialised category. Under EN 1822, H13 is at least 99.95% efficient and H14 is at least 99.995% efficient at the most penetrating particle size. These products are only appropriate where the system is designed for them.

If you are considering a non-standard arrangement, our products and custom air filters can help you identify a suitable option.

Check access, servicing and pressure drop

A filter that performs well on paper can still be a poor choice if it is difficult to reach, inspect or replace. In strata buildings, maintenance access is often the deciding factor, especially where cupboards are tight, roof access is restricted or plant rooms are shared with other services.

Before approving a filter type, check:

• •whether the panel can be removed safely without disturbing nearby services
• •whether there is enough clearance to slide the filter out and in again
• •whether the cabinet door opens fully
• •whether servicing requires roof access, ladder work or permit-controlled entry
• •whether maintenance staff can see the filter condition without dismantling the unit

It is also important to monitor pressure drop where gauges are fitted. That gives a practical indication of how the filter is loading up with dust and whether the system needs attention. Inspection frequency depends on the system, the site conditions and the dust load, so follow the filter and equipment manufacturer instructions rather than relying on a fixed calendar.

If the current setup is difficult to maintain, filter servicing or commercial filter servicing may be worth reviewing as part of the building’s maintenance plan.

Think about washable and replacement options

Some filters are designed to be washable, but that does not make every washable product suitable for every strata application. Always check the product instructions, because washing methods, drying requirements and reuse limits vary by product.

A few practical questions can help narrow the choice:

• •Is the system exposed to heavy dust or greasy air that may make washing impractical?
• •Would a washable product reduce waste without making servicing harder?
• •Is there a clean area available for handling and drying?
• •Would a disposable filter give more consistent performance for this system?

For many strata sites, the best decision is the one that fits the maintenance routine as well as the equipment. A filter that is easy to source, easy to fit and easy to inspect is often more useful than a product with features that are hard to support on site.

Make the selection with the whole building in mind

Strata buildings are rarely simple. A single property can have entry foyers, lift lobbies, basement car parks, plant rooms and shared ventilation systems that all place different demands on filtration. Choosing well means balancing system performance, resident expectations, access constraints and the practical realities of ongoing maintenance.

A sound selection process should always include:

• •confirming the equipment and filter dimensions
• •considering the dust and odour load at the site
• •checking access for safe servicing
• •matching the filter to the system’s airflow and cabinet space
• •reviewing the manufacturer’s instructions and building requirements

If you are unsure whether a standard size will fit or whether a custom solution would be better, it is worth speaking with a supplier who understands commercial and strata systems.

Need help choosing the right filter?

Total Air Filtration is a family-owned air filter manufacturer and supplier based in Hillcrest, Brisbane QLD, and we work with strata managers, property managers and body corporates on practical filter solutions for common-area systems.

For help with a standard replacement or a made-to-order option, call 07 3800 3448 or request a quote. You can also contact us or browse industries we supply to learn more.