A building inspection in Western Australia is a systematic assessment of all visible and accessible building elements, conducted by a qualified inspector in accordance with Australian Standard AS4349.1. If you’re purchasing an established property, it is usually carried out after you sign the contract, but before settlement. The inspection covers the structure, condition, and safety of the home, and results in a written report that identifies defects, safety hazards, and items requiring further attention.
This article gives you a complete breakdown of what a pre-purchase building inspection covers in WA under Bestwest Building’s premium inspection option, what is outside scope, and what you can expect from the report.
| What a Premium Building Inspection Covers at a Glance |
| • Roof exterior: coverings, ridge, hips, valleys, flashings, gutters, and downpipes |
| • Roof space: framing, insulation, ventilation, and visible structural elements |
| • External walls, cladding, windows, and doors |
| • Internal walls, ceilings, and floors |
| • Wet areas: bathrooms, ensuite, and laundry |
| • Sub-floor space (where accessible) |
| • Site features including steps, paths, retaining walls, and fencing |
| • All inspections conducted under AS4349.1 by registered builders |
A Note on Inspection Options
Bestwest Building offers two pre-purchase inspection tiers. The scope described in this article reflects our premium inspection option, which includes the most comprehensive coverage of all building elements. Our structural inspection covers the core building elements. If you’re unsure which option is right for your property, get a free instant quote and we can advise.
The Roof Exterior
The roof is one of the most critical elements of any home and one of the most expensive to repair or replace. Inspectors assess the condition of all roof coverings, including tiles or metal sheeting, along with the ridge, hips, valleys, and all flashings. Gutters and downpipes are included in the visual assessment.
At Bestwest Building, our inspectors use drone technology to inspect roof areas that cannot be safely accessed on foot. This is an important differentiator: many inspection companies are limited to what can be seen from the ground or from the roof edge. Drone-assisted inspection provides a far more thorough assessment of the entire roof plane.
Common defects found at this stage include cracked or slipped tiles, deteriorated pointing, inadequate flashings around penetrations such as chimneys and skylights, and rusted or blocked guttering.
The Roof Space
Where roof space access is available, inspectors enter and assess the internal structure.
This includes:
- Roof framing: rafters, ridgeboards, hanging beams, strutting beams, and collar ties
- Insulation: type, coverage, and condition
- Ventilation: adequacy for the space
- Visible evidence of water ingress, staining, or structural movement
- Extractor fan and rangehood ducting (where accessible)
The roof space is also where thermal imaging can add significant value. Bestwest Building’s thermal imaging capability allows inspectors to identify heat loss, air leakage, and certain concealed concerns not visible to the naked eye under the right conditions.
Note that pest activity in the roof space is assessed as part of a separate timber pest inspection and is not within the scope of a building inspection.
External Walls, Windows, and Doors
The external envelope of the home is inspected for structural integrity, condition, and weatherproofing. Inspectors assess:
- Wall cladding and external finishes: render, brick, fibre cement, or weatherboards
- Window and door frames: condition, operation, and weatherproofing
- Lintels and structural openings
- Flashings at wall-to-roof junctions and around penetrations
- External paintwork condition (where relevant to the underlying substrate)
- Evidence of movement, cracking, or subsidence
Extensions and additions are assessed for condition and how they integrate with the original structure. Buyers should note that inspectors do not verify whether any addition or alteration has council approval or complies with building code requirements. If there are extensions or modifications to the property, buyers should make further enquiries with the relevant local government to confirm adequate approvals are in place.
Internal Areas: Walls, Ceilings, and Floors
Inside the home, the inspector conducts a systematic walk-through of all rooms, assessing:
- Internal walls and linings: cracking, movement, water damage, or other defects
- Ceilings: sagging, staining, cracking, or evidence of prior leaks
- Floors: condition of floor coverings, signs of unevenness, movement, or springiness (which can indicate sub-floor issues)
- Windows and doors: operation, condition, and sealing
- Smoke alarms: presence and positioning (inspectors note whether they appear to be present, but do not test them as this is outside scope)
Wet Areas: Bathrooms, Ensuite, and Laundry
Wet areas receive particular attention due to the prevalence of moisture-related defects in established Perth homes. The inspection covers:
- Visual condition of tiling and grout
- Condition of fixtures, fittings, and seals
- Evidence of water damage to adjoining walls, floors, or ceilings
- Moisture testing to the walls backing onto showers, where accessible, using a moisture meter
Moisture meters are deployed where there is visual evidence of damp or where the location warrants it. Where moisture is detected, the report will note the area and recommend further investigation.
Note that waterproofing compliance cannot be confirmed visually once tiling is installed. Inspectors can note visible indicators of waterproofing failure, but cannot assess whether the membrane was correctly installed without destructive investigation.
Sub-Floor Space
For homes with a suspended floor or accessible sub-floor void, the inspector will enter (where safe and accessible) to assess:
- Structural framing: bearers, joists, and supports
- Evidence of moisture, pooling water, or drainage issues
- Condition of stumps or piers
- Ventilation adequacy
The sub-floor is one of the most commonly overlooked areas by buyers and one of the most important for long-term structural health. Inadequate ventilation or moisture ingress in the sub-floor can lead to timber decay and, in some cases, creates conditions that support timber pest activity.
Site Features and Surrounds
A building inspection also covers the immediate site around the home, including:
- Paths, driveways, and steps: condition and trip hazards
- Retaining walls: condition and evidence of movement
- Fencing: condition and general adequacy
- Visible discharge points and any obvious drainage deficiencies
- Garages, carports, and outbuildings (visible and accessible)
What Is NOT Included in a Building Inspection
Understanding the scope limits is just as important as knowing what is covered. A standard pre-purchase building inspection under AS4349.1 does not include:
- Testing of drainage systems: inspectors visually check gutters and roof drainage but
do not test surface drainage, stormwater systems, or underground drainage - Timber pest assessment: this is a separate inspection requiring a licensed pest
inspector - Swimming pools and associated equipment
- Appliances: ovens, dishwashers, air conditioners
- Asbestos identification (though inspectors may note materials that appear suspect
and recommend further testing) - Verification of council approvals or building permits for any additions or alterations
For the most comprehensive protection before purchasing an established property in WA, Bestwest Building strongly recommends a combined building and pest inspection, which brings both assessments together in a single visit.
What You Receive: The Report
Following the inspection, you receive a same-day digital report with full-resolution photographs documenting each defect or area of concern. The report identifies:
- Major defects requiring urgent attention
- Minor defects and maintenance items
- Safety hazards
- Areas requiring further specialist investigation
Reports are produced by the inspector who attended the property, and Bestwest Building clients have access to direct consultation with their inspector to discuss findings. You can view a sample report on the Bestwest Building website to understand exactly what to expect before you book.
If you have a newly completed home approaching handover, the scope of a practical completion inspection differs from a pre-purchase inspection. That inspection focuses on builder workmanship across the entire completed home, with the objective of identifying defects the builder must rectify before keys are handed over.
How Much Does a Building Inspection Cost in WA?
For a standard pre-purchase building inspection in Bestwest Building’s usual operating area,
pricing varies based on property size, location, and complexity.
| Service | Price Range |
| Pre-purchase building inspection (standard property) | $595–$895 |
| Combined building and pest inspection (standard property) | $790–$1,090 |
Get an instant personalised quote at bestwestbuilding.com.au.
Book a Building Inspection with Bestwest Building
Bestwest Building’s extensive team of highly experienced registered builders has completed 45,000+ inspections across Perth and South West WA. Every inspector is a registered builder, not just a building inspector. All inspections are conducted under AS4349.1, with same-day digital reports and full-resolution photographs for most domestic properties. Get a free instant quote at bestwestbuilding.com.au or call us on (08) 9444 9562.
Frequently Asked Questions About Building Inspections in WA
What does a building inspection include in WA?
A building inspection in WA covers all visible and accessible building elements, including the roof exterior and roof space, external and internal walls, wet areas, sub-floor space (where accessible), and site features. It is conducted under Australian Standard AS4349.1 and results in a written report with photographs. The full scope will vary depending on which inspection option you choose.
Does a building inspection include pest assessment?
No. A building inspection and a timber pest inspection are separate services. A building inspection assesses the structure and condition of the home. A pest inspection assesses for the presence and activity of timber pests including termites. Bestwest Building offers a combined building and pest inspection that covers both in a single visit, which is strongly recommended for all established properties.
Is drainage tested as part of a building inspection?
No. Inspectors visually check gutters, downpipes, and roof drainage, but testing of surface drainage, stormwater systems, and underground drainage is outside the scope of a standard building inspection under AS4349.1.
When is a building inspection carried out in WA?
For established properties, a pre-purchase building inspection is usually carried out after you sign the contract, but before settlement. This gives you an independent condition report before the sale becomes unconditional.
Do I need to be present at the inspection?
You are not required to be present. If you do wish to attend, you will need to get approval from the real estate agent first, as the property is still managed by the seller’s agent.
What is the difference between a pre-purchase inspection and a practical completion inspection?
A pre-purchase building inspection is carried out on an established property before settlement. A practical completion inspection is carried out on a newly completed home at the end of a building contract, before handover. The scope and purpose of each inspection differ significantly. See the Bestwest Building practical completion inspection page for a full breakdown.
