A Pre-Purchase HVAC Checklist for Queensland Townhouses and Units

Buying a townhouse or unit in Queensland is not just about the kitchen, bathroom and car park. If the building has shared air conditioning or mechanical ventilation, the HVAC setup can affect comfort, upkeep and ongoing responsibilities after settlement.

A good pre-purchase check is not about spotting a brand name on a grille. It is about understanding who owns the equipment, how the filters are accessed, and whether the building makes maintenance straightforward or awkward. That can save you from surprises later, especially in strata-titled buildings where responsibilities may be split between owners, body corporate and contractors.

Why HVAC matters in strata properties

Townhouses and units often rely on a mix of individual and shared systems. Some lots have their own split systems, while others connect to common mechanical plant, shared exhaust systems or central ventilation equipment.

When you are buying, ask whether the property has:

• •a dedicated system inside the lot
• •shared condenser or plant equipment in a common area
• •common exhaust fans for bathrooms, laundries or car parks
• •fresh air intake or mechanical ventilation serving multiple lots
• •ceiling or rooftop plant that requires body corporate access

The answer changes who maintains the system, who pays for repairs and how easy it is to replace filters or clean components. If the building has mechanical ventilation, the site requirements should be confirmed with the mechanical services engineer or building owner, particularly where AS 1668.2:2024 is relevant to the installation.

Questions to ask before you make an offer

Start with the seller, agent or strata manager. Ask for practical details, not just a copy of the building brochure.

Useful questions include:

• •What type of HVAC system serves the lot?
• •Is the system fully within the lot, or does it include shared plant?
• •Who is responsible for routine filter replacement or cleaning?
• •Is access to the filter straightforward, or does it require tools, ladders or common-area access?
• •Are there service records available?
• •Has any part of the system been disconnected, capped off or altered?
• •Are there strata by-laws or maintenance rules that affect who can service the equipment?
• •Is there a central or rooftop unit that only a contractor can access?

If the answers are vague, follow up. A system that looks simple from inside the unit may depend on equipment elsewhere in the building.

Ask for documents, not assumptions

Request the available building records before you settle on the property. These may include:

• •strata maintenance logs
• •contractor service reports
• •equipment schedules
• •manuals for the HVAC units
• •filter specifications and product codes
• •any notes about access restrictions or special shut-down procedures

If the seller cannot locate manuals, note the model numbers from the unit nameplate and compare them with the manufacturer instructions. If you need help identifying the right size or style of filter, how to measure an air filter is a useful place to start.

Shared plant: what to look for

Shared plant can be perfectly workable, but it should be understood before you buy. The main issue is not just ownership; it is how practical the system is to maintain.

Check whether the building has:

• •rooftop package units
• •central air handling equipment
• •shared ducted supply or return systems
• •common exhaust fans linked to several lots
• •locked service rooms or plant spaces

When plant is shared, ask who arranges the maintenance call-out and how faults are reported. In some buildings, owners only control in-lot fixtures, while the body corporate handles the main equipment. In others, maintenance may be split between the owner and the strata scheme.

A building that has clear maintenance records and accessible plant rooms is usually easier to manage than one where no one is certain who last serviced the system.

Filter access is a practical test worth doing

Filter access is one of the most important questions because it affects whether the system gets maintained properly. If a filter is hard to reach, it is more likely to be overlooked.

Before you buy, try to find out:

• •where the filter is located
• •whether the access panel is inside the lot or in a common area
• •whether the panel needs a special key, screwdriver or tool
• •whether the filter size is standard or custom
• •whether there is enough space to remove and inspect it without damage

In some units, the filter sits in a return air grille inside a hallway or living area. In others, it may be inside a ceiling cavity, cupboard, garage or plant room. Shared systems can also have multiple filters in different places.

If the filters are a non-standard size, keep in mind that custom air filters may be needed. That is not a problem by itself, but it is worth confirming that future replacements will be easy to source and install.

What happens if access is awkward?

If access requires a contractor every time, maintenance can become more dependent on scheduling and approval. That may be fine, but you should know it in advance.

Look for:

• •missing or painted-shut access panels
• •cramped ceiling spaces
• •filters blocked by stored items
• •plant rooms with limited clearance
• •grilles that do not show the filter condition clearly

If the filter cannot be checked without trouble, ask whether the building has a servicing arrangement already in place or whether the owner is expected to organise it. For ongoing support, filter servicing and commercial filter servicing can be useful references for building managers.

Who is responsible for maintenance?

This is the question that often matters most after settlement. In a townhouse or unit, responsibility may sit with the owner, the body corporate, a building manager or a combination of these.

Clarify responsibility for:

• •routine inspection of filters
• •replacement or cleaning of filters
• •fan and motor servicing
• •duct cleaning where required
• •fault reporting and repair coordination
• •access to roof or common plant areas

Do not assume that because the equipment is inside the lot, the owner automatically controls all maintenance. Likewise, do not assume the body corporate will handle every part of the system just because some components are shared.

If you are a strata or property manager, make sure the maintenance plan is written down and passed on with the property records. A clear schedule for inspection, combined with the manufacturer’s instructions, helps avoid confusion about what needs attention and when.

Choosing the right filter for the building

Once you know who maintains the system, it is easier to work out what kind of filter is needed. The right product depends on the equipment design, the space available and the air quality demands of the site.

When assessing a replacement filter, confirm:

• •the exact dimensions
• •the frame style and depth
• •the airflow direction if marked
• •whether the filter is disposable or a specific washable product
• •whether the material suits the equipment manufacturer’s requirements

Some filters are designed to be washable, but check the product instructions before reusing anything. Inspection frequency should depend on the system, the site conditions and the dust load, and pressure drop should be monitored where gauges are fitted.

If the building uses a rated filter system, remember that MERV, EN 779 and ISO 16890 do not convert directly. EN 779 classes such as G3, G4 and F5-F9 are still commonly referred to in Australia, even though the standard has been superseded by ISO 16890. For higher-efficiency applications, H13 and H14 are HEPA classes under EN 1822, with H13 at greater than or equal to 99.95% efficiency and H14 at greater than or equal to 99.995% efficiency at the most penetrating particle size.

A simple checklist for buyers, managers and agents

Before signing, make sure you can answer these questions clearly:

• •What HVAC equipment serves the property?
• •Is any part of the system shared with other lots?
• •Where is the filter located?
• •How do you access it?
• •Who is responsible for inspections and replacement?
• •Are manuals and service records available?
• •Are there any special building rules for maintenance access?
• •Are replacement filters standard size or custom?

If the answers are unclear, treat that as a maintenance risk, not a minor detail. In strata buildings, small access issues can become ongoing management issues.

Talk to Total Air Filtration before you buy

If you need help identifying the right filter type, checking dimensions or planning for a shared plant setup, Total Air Filtration can supply or make the right filters for the job. We are a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, established 2009.

Call 07 3800 3448 or request a quote. You can also view our products or contact us if you would like to talk through a townhouse or unit HVAC setup before settlement.