What a Proper In-Home AC Assessment Actually Covers

What a Proper In-Home AC Assessment Actually Covers

A proper AC assessment covers a full check of your power capacity, airflow, and usage needs to make sure the system is correctly sized and compliant. However, most Brisbane installers will just glance at your switchboard and hand you a quote before they’ve even checked your roof space properly.

Meanwhile, you miss the insulation quality, an explanation of whether your electrical panel can handle the load, and no confirmation that your walls can support the indoor unit without custom brackets.

In this article, we’ll walk through the process of a proper AC assessment. You’ll learn about the hidden costs that often get buried in vague quotes, and what paperwork protects you under Australian Consumer Law when your installer cuts corners.

Let’s find out everything about a thorough AC assessment.

What Happens During Your Initial Assessment Process?

During your AC assessment, your technician should walk through room layouts and insulation, electrical capacity at your switchboard, and wall construction for mounting units. This process tells you whether your home needs extra work before installation can even start.

This is what gets checked in each stage.

Site Inspection and Floor Plan Review

The assessor measures each room’s square metreage, notes your ceiling heights, and checks which direction your windows face. They’ll also climb into your roof space to assess insulation quality and look for obstructions that might block ductwork paths.

Your floor plan gets reviewed to identify the best spots for return air grilles and where refrigerant lines can run without cutting through structural beams.

The reason insulation is so important is that properly sized systems that meet energy efficiency standards save Queensland homeowners an average of $185 per year on electricity costs.

Switchboard and Circuit Capacity Check

An electrician examines your switchboard to confirm it can handle your new AC’s power draw without overloading existing circuits. It’s because older homes built before 2000 often have 63-amp switchboards, but modern ducted systems need 80-100 amps to run safely alongside your other appliances.

So they check if you need a dedicated circuit with an isolator and RCD protection for the outdoor compressor unit. Once they’ve assessed your electrical capacity, they measure the cable run distance from your switchboard to where the outdoor unit will sit. They’ll note any obstacles like garden beds or pathways that complicate the installation.

Wall and Ceiling Construction Analysis

Brick homes need different mounting hardware than weatherboard houses. Some older Queensland homes have asbestos sheeting that even requires licensed removal before any drilling. That’s why external walls get assessed for drilling refrigerant lines through to the outdoor unit.

Drawing from our experience with Brisbane homes built in the 1970s and 80s, we often find single-brick construction that needs reinforced brackets because the mortar has degraded over time.

The installer taps your walls to locate studs and checks if you’ve got brick, weatherboard, or plasterboard construction for mounting the indoor unit securely. They inspect your ceiling space for ductwork routing and look for existing plumbing or electrical wiring that blocks clear paths.

How Technicians Calculate Your Units

Your installer assesses factors like room size, insulation, ceiling height, sunlight, occupancy, and heat sources to calculate the correct cooling load. They should be calculating based on your specific home conditions, instead of throwing out a generic number based on square metreage alone.

Let me break this calculation down for you:

• Basic Calculation: Your room dimensions get multiplied by .15-0.160 kilowatts per square metre for baseline cooling capacity. Say, a 150 square metre home needs roughly 22.5kW to 24kW from that formula alone.
• Window Factors: West-facing windows add 2-3 kilowatts to your total load, and single-glazed windows lose three times more heat than double-glazed ones (and yes, most installers skip this step entirely). So you need 30% more capacity just to fight heat gain coming through poor-quality glass.
• Structural Additions: High ceilings above 2.4 metres increase your cooling load because there’s more air volume to condition. On top of that, poor roof insulation adds another 20-25% on top of everything else.

Getting these calculations wrong means your system runs constantly without reaching the temperature you set. In fact, heating and cooling account for 20-50% of energy use in Australian homes, which is why proper capacity calculations are important for your long-term running costs.

The Hidden Costs Most Quotes Don’t Mention Upfront

Knowing about these hidden costs beforehand allows you to avoid that awkward moment when your installer adds $800 to the bill on installation day. These extras show up once installers start measuring and drilling on-site, and most quotes list them as “subject to site inspection” without explaining what that actually means.

Take a look at what brings in these additional fees:

• Multi-Storey Access Fees: Second-storey installations usually need scaffolding or elevated work platforms. They end up adding $300-$800 to your final bill.
• Electrical Upgrades Beyond Standard Circuits: Older switchboards lacking capacity require upgrades to handle new AC load, and that can cost an extra $400-$1,200. 
• Custom Bracket or Mounting Solutions: This happens when your outdoor unit can’t sit on a standard concrete pad. You may need wall mounting or elevated platforms instead, adding $200-$500 to installation costs. 
• Exposed Piping Extensions Past 3 Metres: The standard quote assumes a basic back-to-back installation where indoor and outdoor units sit within 3 metres of each other. That’s why refrigerant lines longer than 3 metres cost $80-$120 per additional metre for copper piping. 
• Old Unit Removal and Disposal: Through our installations across Queensland, we’ve found that most homeowners assume removing their old split system is automatic. However, it requires licensed refrigerant handling and proper disposal certificates. So a proper removal costs $150-$350.
• Wall or Ceiling Repairs After Installation: Installers often drill through walls for piping and cables. Patching those holes, repainting, or fixing damaged plasterboard adds $100-$400 to your total spend. 

Your quote should break down every potential extra cost in writing, instead of hiding them behind vague terms like “subject to site conditions.” That’s why you need to ask for a detailed scope document that lists what’s included and what triggers additional fees before you sign anything.

Documentation You’ll Receive After the Assessment

Once your technician finishes measuring and planning, you should get four documents that protect you if anything goes wrong. These documents help you get the full explanation before any work begins.

These are the documents you should be receiving:

• Written Quote Breakdown
• Installation Scope Document
• Electrical Compliance Certificate
• Warranty Details

Since 2004, all residential air conditioners have been subject to Minimum Energy Performance Standards, and your compliance certificate proves your system meets these requirements.

Your installer should provide these before asking for any deposit or signing contracts. When you receive them, keep copies of all four documents in a safe spot because you’ll need them if problems show up months or years after installation.

How Long Does It Actually Take to Assess?

Assessment time depends on your home type and system choice, but they usually range from 30 minutes to two hours. A thorough process ensures all factors are considered for optimal performance and efficiency.

Here’s a general idea for each type of assessment:

• Basic Split System Assessments: 30-45 minutes (for single-storey homes) 
• Ducted System Assessments: 60-90 minutes 
• Multi-Storey Homes Or Complex Layouts: 90-120 minutes

Rushed assessments under 30 minutes for ducted systems are red flags that the installer is guessing rather than measuring properly. And that can lead to poor system performance and costly fixes down the line.

Get Your AC Assessment Right This Time

A good assessment reveals how your home needs electrical upgrades, structural reinforcement, and additional ductwork before installation begins. We suggest comparing quotes by checking what’s included versus what’s excluded, not just the bottom-line price difference.

Different installers have different skill levels with various manufacturers, and you want someone who’s installed your exact model before. So ask installers about their experience with your specific home construction type and the unit brand they’re recommending.

Our team at Gtallen provides detailed assessments for Brisbane homes and breaks down every cost upfront so you know exactly what you’re paying for before work starts. Visit us to book your assessment during the shoulder seasons for better availability and faster turnaround times.