Custom Air Filters: What Information to Provide When Ordering

Ordering custom air filters is straightforward when you give the supplier the right information from the start. The more complete your order details are, the better the chance of getting a filter that fits properly, suits the equipment, and performs as expected in service.

At Total Air Filtration, a family-owned air filter manufacturer and supplier in Hillcrest, Brisbane QLD, we regularly work with facility managers, mechanical contractors and industrial buyers who need custom filters for commercial and industrial systems. If you are preparing an order, here is the exact information to have ready.

Start with the filter size and exact measurements

The most important detail is the filter size. Do not rely on a nearby size or a nominal label if you can measure the existing filter or the filter housing directly.

Provide:

• •Length, width and depth in millimetres or metres, depending on the application
• •Inside dimensions of the frame or filter slot if the filter fits into a housing
• •Outside dimensions if the filter sits in a visible frame or cassette
• •Tolerance or clearance if the filter must slide into a tight space
• •Any unusual shape such as square, rectangular, wedge, panel, bag or cylindrical form

If you are not certain how to measure the filter, use our guide on how to measure an air filter. That is often the fastest way to avoid an order delay.

If the filter has to fit an existing unit, also note whether the dimensions refer to the filter media itself, the frame, the gasket, or the full assembled filter.

Tell the supplier what the filter is for

The application matters because different systems need different filter constructions. A filter for a rooftop HVAC unit is not the same as one used in a dustier industrial process, a fresh air intake, or a specialised room.

Include details such as:

• •The equipment type and model, if available
• •The system location such as supply air, return air, intake air or exhaust air
• •The site environment such as office, workshop, food production area, warehouse, plant room or manufacturing space
• •The type of particles or contaminants you are dealing with, if known
• •Whether the filter is for general ventilation or a specific process

If the building or plant needs to align with ventilation requirements, site requirements should be confirmed with the mechanical services engineer or building owner, including any relevant expectations under AS 1668.2:2024.

Specify the filter media and performance needs

The media is the working part of the filter, so it should be selected for the application rather than guessed from appearance alone. Suppliers need to know whether you want a coarse pre-filter, a finer panel filter, a bag filter, or another construction.

Provide as much of the following as you can:

• •Media type if known, such as synthetic, glass fibre, or another specified media
• •Desired filtration stage, such as pre-filter or final filter
• •Target rating or class, if your system uses one
• •Resistance to dust loading, if the site is dusty or the filter is expected to hold a lot of particulate
• •Whether low resistance is important for airflow in the system
• •Whether washable construction is needed; some filters are designed to be washable - check the product instructions

If you are using a rating system, be clear about which standard applies. MERV, EN 779 and ISO 16890 do not convert directly, so it is best to state the rating used by the equipment manufacturer or the site specification rather than trying to translate it yourself. EN 779 classes such as G3, G4 and F5-F9 are still widely used in Australia, even though they have been superseded by ISO 16890.

For HEPA applications, specify the exact class required. H13 is at least 99.95% efficiency at the most penetrating particle size under EN 1822, and H14 is at least 99.995% under the same standard. If you are not sure which class is required, confirm it with the engineer responsible for the system.

Include the frame type and construction details

The frame can make the difference between a filter that fits properly and one that leaks, rattles, or cannot be installed. Suppliers need to know exactly how the filter is mounted and what it is made from.

Tell us:

• •Frame material such as galvanised steel, aluminium, cardboard, plastic, MDF, stainless steel or another specified material
• •Frame depth and profile
• •End style or header style if the filter is bag or pocket style
• •Whether a gasket is needed and where it is placed
• •Whether the filter uses a seal, flange, rail or clip system
• •Any special strength needs for vibration, airflow or handling

If you are replacing an existing filter, photos of the old filter and the housing can be very helpful. A clear image of the label, the frame edges and the installation orientation can save time and reduce the chance of getting the wrong build.

Confirm quantity, frequency of change and packaging needs

Suppliers also need to know how many filters you need and how they should be supplied.

Include:

• •Quantity required for the first order and any repeat order estimate
• •Whether the filters are for one site or multiple sites
• •Any labelling or packing requirements for staged maintenance or site distribution
• •Delivery address and access details if the site has loading restrictions or receiving hours
• •Whether you want spares held for future orders

It is also useful to tell the supplier how often the filter is normally inspected or changed in your system. That timing depends on the equipment, site conditions and dust load. Follow the filter and equipment manufacturer instructions, and monitor pressure drop where gauges are fitted.

For ongoing support, filter servicing and commercial filter servicing can help keep replacement planning practical when you are managing multiple units or sites.

Note any special site conditions or constraints

Not every filter order is standard. If the site has unusual conditions, mention them early so the supplier can recommend the right construction.

Useful details include:

• •High dust loading
• •Moisture, humidity or condensation concerns
• •Temperature extremes
• •Corrosive atmosphere
• •Food-safe or cleanroom requirements
• •Noise or vibration considerations
• •Space restrictions around the housing
• •Access issues for maintenance crews

If the filter is being used in an environment with people who have respiratory concerns, the filter can still be selected for particle capture, but any health questions should be discussed with a medical professional.

The fastest way to avoid delays

A complete order usually includes the following in one message or email:

• •Exact dimensions
• •Application and equipment type
• •Media or performance requirement
• •Frame type and any gasket details
• •Quantity needed
• •Site conditions or special constraints
• •Photos of the existing filter or housing, if available

If you already know the product type you need, you can also browse our products or send through the specifications for custom air filters. If you are unsure about the details, a photo and measurements are often enough for the supplier to ask the right follow-up questions.

Talk to Total Air Filtration

Getting the details right at the beginning saves time later and helps ensure the replacement suits the system. Total Air Filtration can supply or make the right filter for your application, and we can help you work through the information needed for a custom order.

Call 07 3800 3448 or request a quote. You can also contact us if you want to confirm the measurements before placing an order.