The most common building and pest inspection issues facing property buyers

In Australia’s property market, building and pest inspections are one of the most important forms of due diligence a buyer can undertake.

Yet despite their importance, many buyers underestimate what these inspections reveal, or misunderstand how frequently certain issues arise across different property types and locations.

I have consistently observed that while no two properties are identical, there are recurring themes in building inspection reports that buyers should be aware of. Understanding these common issues not only helps buyers avoid costly surprises, but also allows them to approach pricing and negotiating with a clearer sense of risk and value.

Below are some of the most common building issues encountered in property inspection reports, and why they deserve careful attention.

Water ingress and moisture problems

Water is one of the most prevalent and potentially damaging issues identified in building inspections. It can present in many forms, including roof leaks, blocked gutters, poor drainage, rising damp, and failed waterproofing in wet areas such as bathrooms and laundries.

At first glance, these issues may appear minor. However, prolonged exposure to moisture can lead to structural deterioration, mould growth, timber rot, and internal damage to walls and ceilings. In many cases, the visible signs such as ceiling stains, or bubbling paint are only the surface indicators of a deeper problem.

Properties with inadequate drainage or ageing roofing systems are particularly susceptible. In established suburbs, older homes often require ongoing maintenance to manage these risks effectively, particularly in the colder states.

Termite activity and pest damage

Termites remain one of the most significant pest risks to residential property in Australia.

Unlike many other building issues, termite damage can go unnoticed for extended periods, particularly if the infestation is concealed within wall cavities, subfloors or roof structures.

A pest inspection typically looks for both active infestations and evidence of past activity. Even where termites are no longer present, the damage they leave behind can compromise structural integrity and require expensive remediation.

Properties in warmer climates, including parts of Brisbane and regional areas with high humidity, are especially prone to termite risk. However, no location is immune, and regular inspections and preventative measures are essential for any long-term owner.

Structural movement and foundation issues

Structural concerns are another common finding in building reports, particularly in older properties. These issues may present as cracking in walls, uneven floors, sticking doors or windows, or visible movement in the building’s structure.

In some cases, the underlying cause may be minor and manageable. In others, it may indicate foundation movement, inadequate original construction, or deterioration of structural supports such as stumps or slabs.

Timber subfloor homes, common in many established suburbs, may require re-stumping over time. This process can be costly, and once completed, often triggers additional repairs such as plaster patching, re-leveling of floors, and re-alignment of internal elements. However, reblocking brick external walls is even more costly and often involves the advice of a structural engineer.

Understanding whether structural movement is mild or significant is critical, and often requires professional interpretation beyond the summary provided in a standard report. Building inspectors will generally recommend the engagement of a structural engineer in these circumstances.

Roofing defects and maintenance issues

The roof is one of the most important protective elements of any property, yet it is also one of the most commonly neglected.

Building inspections frequently uncover issues such as cracked or missing tiles, rusted metal roofing, deteriorated pointing, blocked gutters, or ageing flashings. While some of these may appear minor in isolation, collectively they can lead to water ingress and broader maintenance concerns.

In many cases, roofs are not replaced until they fail, meaning buyers of older homes may inherit roof tiling/sheeting nearing the end of its useful life.

Factoring in the potential cost of roof repairs or replacement is an important consideration when assessing value. Depending on the location of the property, costs may vary. For example, in regional or remote areas, labour and freight surcharges often surpass city trades.

Non-compliant or unapproved structures

Another recurring issue identified in inspections is the presence of structures or renovations that have not been approved by local council.

This can include extensions, garages, decks, pergolas, or internal alterations such as converted rooms or relocated plumbing and electrical systems.

While some of these works may have been completed to a reasonable standard, the absence of formal approval can create complications and liability for the new buyer.

Unapproved works may impact insurance coverage, future resale, and in some cases, may require retrospective approval or rectification. Buyers should always verify whether alterations have been properly documented and approved where required.

In established markets, where renovations are common, this issue is particularly prevalent and requires careful due diligence. Once the purchaser settles the purchase, the liability rests completely with them.

Asbestos and hazardous materials

In properties built prior to the late 1980s, asbestos is still commonly found in a range of building materials, including wall sheeting, eaves, fencing and roofing.

While the presence of asbestos is not uncommon, it does require careful management. In many cases, asbestos-containing materials are safe if left undisturbed, but any renovation or demolition work must be carried out in accordance with strict safety guidelines.

The cost of removal can vary significantly depending on the extent and location of the material. For buyers planning future renovations, identifying asbestos early is essential to avoid unexpected costs and compliance issues.

In addition, any rental property with known asbestos requires this to be disclosed to the renters.

Plumbing and electrical concerns

Ageing plumbing and electrical systems are another frequent finding in building inspections, particularly in older properties that have not been fully updated.

Issues may include outdated wiring, insufficient switchboards, ageing pipework, or leaks within concealed plumbing systems. While these issues are not always immediately visible, they can pose both safety risks and future repair costs.

Upgrading these systems can be a significant expense, particularly in properties where access is limited or where upgrades must be completed in stages.

In some states (including Victoria), gas and electricity compliance certificates are required prior to advertising for rent and/or letting. Where possible, investors should ideally endeavour to negotiate access prior to settlement for the compliance tests.

The bigger picture for buyers

Building and pest inspections are not designed to eliminate all risk, nor do they represent an opportunity to negotiate the price down further. While discounting sometimes applies, the intended purpose of the inspections is to provide clarity around the condition of a property at a point in time, and to highlight areas that may require attention either immediately or in the future.

Experienced buyers agents do not approach inspections as a pass or fail exercise. Instead, they use the information to understand the property’s strengths and weaknesses, assess likely costs, and determine whether the asset aligns with their client’s strategy and budget.

Common building issues are not necessarily deal-breakers. Many properties will have a combination of minor and moderate concerns. What matters is whether those issues are understood, appropriately costed, and acceptable relative to the purchase price and long-term goals.

Ultimately, a building inspection is one of the most valuable tools available to a buyer. When used properly, it transforms uncertainty into informed decision-making, allowing buyers to proceed with greater confidence and a clearer understanding of what they are acquiring.

A comprehensive inspection enables a buyer to set appropriate pricing limits and make provisions for future costs.