What Tenants Should Know Before a Filter Upgrade in an Office Tower

An office tower filter upgrade can look straightforward from the outside, but it often involves more than swapping one filter for another. Access to plant rooms, changes to filter frames or holding systems, airflow adjustments and tenant communication can all affect how the building operates during the work.

For property managers, facility managers and tenants, a little planning helps avoid disruption and makes it easier to keep the building running smoothly while the upgrade is carried out.

Why filter upgrades are more than a simple swap

A filter upgrade may be part of a broader building tune-up, or it may be driven by a change in occupancy, indoor air requirements, maintenance observations or a review of the existing ventilation setup. In some cases, the new filter is a different size, depth or construction, which means the change can affect the mechanical system as well as the filter rack itself.

Before work starts, it helps to confirm:

• •the current filter size, thickness and frame type
• •whether the new filter has a different pressure drop characteristic
• •whether any seals, tracks, clamps or access doors need attention
• •whether the upgrade is being done across one floor, several levels or the whole tower
• •whether the system has space for a deeper or higher-efficiency filter arrangement

If the upgrade is being considered as part of a ventilation review, site requirements should be confirmed with the mechanical services engineer or building owner, including any relevant AS 1668.2:2024 considerations.

Access, timing and work area planning

Filter changes in office towers often require access to roof plant, ceiling voids, risers, service corridors or mechanical rooms. That means tenants may notice contractors moving through common areas, temporary barriers, or brief interruptions to access around plant spaces.

Good planning should cover:

• •which areas need contractor access
• •whether after-hours work is preferred to reduce disruption
• •how workers will reach filters without affecting tenancy security
• •whether loading docks, lifts or back-of-house corridors are needed for materials
• •how waste filters will be removed from the site

If a tenant’s space includes local filtration units, fan coil equipment or specialist filters, the building team should confirm in advance whether the tenant or the base building contractor is responsible for access and shutdowns. This avoids confusion on the day and helps make sure the right people are on site.

Equipment changes that may come with a better filter

A new filter is not always a direct like-for-like replacement. Depending on the existing equipment, the upgrade may require small mechanical changes to accommodate the new product properly.

Possible changes can include:

• •replacing or adjusting filter rails, frames or clips
• •checking gasket surfaces for gaps, wear or distortion
• •adding pre-filters or changing the filter staging arrangement
• •reviewing fan settings if the new filter presents a different resistance to airflow
• •confirming the filter direction and installation depth

This is especially important where the building has older equipment or a mixed system with different filter types in different areas. If the new filter is not seated correctly, air may bypass the media and reduce the effectiveness of the installation.

If a project involves custom sizes or unusual housings, custom air filters may be the best way to match the equipment rather than forcing a standard product to fit poorly.

Pressure drop and airflow: what occupants may notice

One of the main operational impacts of a filter upgrade is pressure drop. Filters with finer media or a more demanding construction can increase resistance to airflow if the system is not adjusted to suit. That does not automatically mean the upgrade is a problem, but it does mean the mechanical team should check the impact on the fan and the wider system.

When pressure increases, occupants may notice:

• •reduced airflow from some diffusers
• •a change in system noise
• •pressure imbalances between areas
• •doors that feel different to open or close
• •temperature control that seems less even than before

The building team should monitor pressure drop where gauges are fitted and follow the filter and equipment manufacturer instructions. Inspection frequency will depend on the system, site conditions and dust load, rather than a fixed calendar schedule.

If the building uses a specialist filtration setup or the upgrade is part of an ongoing maintenance program, commercial filter servicing can help keep the system practical to maintain.

Communicating with tenants before and during the work

Clear communication makes filter upgrades much easier to manage. Tenants do not need every technical detail, but they do need to know what is happening, when it is happening and whether anything in their day-to-day operation may be affected.

A useful tenant notice should include:

• •the areas affected
• •the expected work window
• •whether there will be any brief shutdowns or reduced airflow
• •whether access to ceilings, plant rooms or adjacent areas is required
• •who tenants should contact if they have access concerns

For tenants with sensitive operations, meeting rooms, print areas or specialist equipment, early notice is especially important. If there are odour concerns, dust-sensitive processes or unusual after-hours requirements, the building manager should flag these before work begins so the contractor can plan accordingly.

If occupants have health concerns, they should seek medical advice rather than rely on building comments about the filter upgrade.

Choosing the right replacement filter for the tower

The best replacement filter is the one that suits the building’s actual system, maintenance access and operating conditions. In Australian commercial buildings, you may hear older EN 779 class names such as G3, G4 or F5 to F9, while ISO 16890 is now widely used as well. These ratings do not convert directly, so they should be treated as separate classification systems rather than one-to-one equivalents.

For specialist applications, HEPA filters are sometimes used. Under EN 1822, H13 is at least 99.95% efficient and H14 is at least 99.995% efficient at the most penetrating particle size. That level of filtration is not needed in every office tower, and the building design should guide what is appropriate.

A practical filter selection process usually looks at:

• •the existing equipment and filter space
• •the desired balance between airflow and particle capture
• •maintenance access and replacement handling
• •the building’s dust load and local conditions
• •whether the filter needs to be standard or custom made

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

If you are measuring an existing filter before ordering a replacement, our guide on how to measure an air filter can help avoid mistakes.

Making the upgrade smooth for property and facility teams

A well-planned filter upgrade is usually easiest when everyone understands their role. The property manager coordinates approvals and tenant communication, the facility manager confirms access and plant impacts, and the contractor supplies the correct product and installation support.

Before work starts, it helps to confirm:

• •who is authorising the upgrade
• •who will provide access to plant and riser spaces
• •whether the upgrade affects one system or several
• •how the building will monitor pressure after installation
• •what to do if the new filter does not fit as expected

If the building also has ongoing maintenance needs, a regular servicing plan can reduce last-minute surprises. For broader support, filter servicing is a practical place to start.

Total Air Filtration can help with the right fit

Total Air Filtration is a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, established 2009. We supply standard and custom solutions for office towers and other commercial sites, and we can help match the filter to the equipment and access conditions on your building.

If you are planning a filter upgrade and want to make sure the replacement suits the system, call 07 3800 3448 or request a quote. You can also browse our products or contact us if you need help working out the next step.