How Sums Insured and Replacement Cost Valuations Affect Strata Insurance

The information on this website is general in nature and does not take into account your objectives, financial situation, or needs. Consider seeking personal advice from a licensed adviser before acting on any information.

For strata committees, owners corporations, body corporates and apartment owners, the annual strata insurance renewal can raise an important question: why has the premium changed, and is the building insured for enough?

A major part of the answer is the strata insurance sum insured. This figure is usually informed by a replacement cost valuation, which estimates what it may cost to rebuild or reinstate the insured property after a major loss. The higher the sum insured, the more exposure the insurer may be taking on, which can influence the premium. But setting the figure too low can create a serious underinsurance risk.

This article explains how sums insured and replacement cost valuations affect strata insurance premiums and cover adequacy. It is general information only and does not take into account the needs, objectives or circumstances of any particular strata scheme. For broader context on cover options, you can visit Insurance for Strata.

Why sums insured matter in strata insurance

The sum insured is the nominated amount of cover for insured property under the strata insurance policy. In simple terms, it helps set the maximum amount the insurer may pay for certain insured losses, subject to the policy wording, limits, excesses and exclusions.

For a strata property, the sum insured commonly relates to the building and common property. Depending on the scheme, policy and applicable state or territory requirements, this may include items such as:

• the main building structure;
• shared walls, floors, ceilings, roofs and stairways;
• lifts, plant rooms and building services;
• common-area fixtures and fittings;
• shared facilities such as foyers, car parks, pools, gates or gardens;
• outbuildings or structures forming part of the insured common property.

The exact boundary between what is covered by strata insurance and what individual owners must insure can vary by state or territory, strata plan and policy wording. Apartment owners should not assume strata insurance covers personal contents, personal valuables, tenant belongings or improvements that fall outside the strata policy.

Replacement cost valuation strata basics

A replacement cost valuation for strata is an estimate of what it may cost to rebuild, replace or reinstate the insured building and common property after an insured event. It is not the same as the property's market value, purchase price or council rates valuation.

Replacement cost valuations are important because strata buildings can be complex. Rebuilding a multi-unit property may involve demolition, engineering, compliance work, professional consultants, approvals, access constraints and staged construction. These costs can be materially different from the amount an apartment or the whole site might sell for.

A professional valuation can help the committee or owners corporation choose a more defensible sum insured. It does not guarantee a claim outcome or eliminate all underinsurance risk, but it can provide a more informed basis than relying on historic figures or simple guesswork.

Market value is not the same as rebuilding cost

One common mistake is assuming the strata insurance sum insured should match the property's market value. In practice, the two figures measure different things.

What should a rebuilding cost estimate consider?

A replacement cost valuation should usually look beyond the visible building. The cost of reinstating a strata property can include many components that are easy to overlook when reviewing a renewal schedule.

Demolition and debris removal

After a major fire, storm, impact event or structural loss, the site may need to be made safe before rebuilding can begin. Demolition, debris removal, hazardous material handling and site clearance can add significant cost. If these allowances are not considered, the sum insured may not reflect the full reinstatement task.

Professional fees and approvals

Rebuilding may require architects, engineers, surveyors, project managers, certifiers, legal input and strata management support. Planning approvals and compliance work can also affect timeframes and costs. Some policies include separate limits for these expenses, while others may include them within the building sum insured or apply specific conditions.

Building code and compliance changes

A building that was compliant when first constructed may need upgrades if it is substantially rebuilt later. This could involve fire safety, accessibility, energy efficiency, structural or materials-related requirements. Whether and how these costs are covered depends on the policy wording and the circumstances of the claim.

Escalation during the policy period

Construction costs can change between the date of the valuation, the policy start date and the date of a claim. Labour shortages, material supply issues and inflation can all affect rebuilding cost. Some policies include an escalation or indexation allowance, but committees should understand how it works and whether it is sufficient for their property.

Common property and shared facilities

Strata schemes may include more than the main apartment building. Shared driveways, boundary walls, lifts, pools, gyms, rooftop areas, solar infrastructure, mechanical services, intercom systems and landscaping may need to be considered where they form part of insured property. Exclusions and limits can vary, so the policy schedule and wording should be reviewed carefully.

How the sum insured affects strata insurance premiums

Insurers price strata insurance by assessing both the likelihood of a claim and the potential size of a claim. The sum insured is important because it represents the potential financial exposure attached to the insured building and common property.

All else being equal, a higher sum insured may increase the premium because the insurer may need to allow for a larger possible payout. However, premiums do not move only because of the sum insured. Insurers may also consider location, claims history, construction type, building height, occupancy, risk controls, maintenance history, excess levels and market conditions.

This means two buildings with a similar sum insured can still have different premiums. A well-maintained low-rise scheme in one location may be assessed differently from an older complex with water ingress issues, repeated claims or exposure to natural hazards.

If you are modelling possible inputs that may influence estimated premiums, the site's strata insurance calculator may help you think through the types of information that can affect pricing. Any estimate should be treated as indicative only, as actual premiums depend on insurer criteria, policy terms and the scheme's circumstances.

The risk of strata underinsurance

Strata underinsurance occurs when the sum insured is not enough to meet the cost of reinstating the insured property after a loss. This risk is most obvious after a total loss, but it can also matter in large partial losses where repairs are extensive.

Underinsurance can create practical and financial problems for the strata scheme, including:

• a shortfall between the claim payment and the actual cost of reinstatement;
• pressure to raise special levies from owners;
• delays while the committee considers cheaper repair options or alternative funding;
• disputes among owners about affordability and rebuilding decisions;
• difficulty satisfying lender, owner or legislative expectations around adequate insurance;
• possible application of policy conditions, such as averaging or co-insurance clauses, if they form part of the policy.

Not every strata policy handles underinsurance in the same way. Some policies may contain specific clauses dealing with underinsurance, limits or reinstatement obligations. Committees should review the policy wording rather than assuming the insurer will pay whatever it costs to rebuild.

Can a strata scheme be overinsured?

It is also possible for a sum insured to be higher than the realistic reinstatement cost. This may mean the scheme pays more premium than necessary, although the impact will depend on the insurer's rating approach and policy structure.

Overinsurance does not usually mean the strata scheme receives a windfall after a claim. Insurance is generally intended to put the insured party back into the position contemplated by the policy, not to create a profit. Claim payments remain subject to the actual loss, policy limits, policy conditions and insurer assessment.

The goal is not to choose the lowest possible sum insured or the highest imaginable figure. The goal is to choose a well-supported amount that reflects the likely rebuilding cost and the requirements of the policy and relevant strata laws.

Other premium factors committees should still review

Although this article focuses on sums insured and valuations, they are only part of the premium calculation. Committees reviewing renewal costs should also consider the broader risk profile of the scheme.

Building location

Location can affect exposure to flood, bushfire, cyclone, storm, hail, coastal conditions, theft or other risks. Insurers assess these risks differently, and pricing can change as their view of an area changes.

Building age, construction and condition

Older buildings or buildings with known defects, water damage, outdated services or combustible materials may attract closer underwriting scrutiny. Regular maintenance, timely repairs and clear records can help demonstrate active risk management, although they do not guarantee lower premiums.

Building usage and occupancy

Short-term letting, mixed commercial use, vacant lots and high tenant turnover can influence how an insurer views risk. Committees should ensure the insurer is given accurate occupancy and usage information at renewal.

Claims history

Frequent or severe claims can affect premiums and excesses. A scheme with repeated water damage claims, for example, may need to show what steps have been taken to reduce recurrence.

Excess levels

The excess is the amount payable by the insured before the insurer contributes to a claim, subject to the policy. Increasing an excess may reduce premiums in some cases, but it also increases the amount the scheme or affected owners may need to pay when a claim occurs. The trade-off should be considered carefully.

When should a strata valuation be reviewed?

There is no single review timetable that suits every strata scheme across Australia. State and territory requirements, insurer expectations, lender expectations and scheme circumstances can differ. Committees should check the requirements that apply to their scheme and obtain professional guidance where needed.

As a practical matter, a replacement cost valuation may need attention when:

• the existing valuation is several years old;
• major capital works, renovations or extensions have been completed;
• new shared facilities or building services have been added;
• construction costs have moved significantly;
• the insurer, broker or strata manager asks for updated information;
• the committee is concerned the policy schedule no longer reflects the property;
• there has been a significant change in the scheme's risk profile.

Some schemes apply indexation between professional valuations. Indexation can be useful, but it is not a substitute for periodically reassessing the underlying rebuilding cost, particularly where the property has changed or construction market conditions have shifted.

Questions to ask before renewing your strata insurance

Before accepting a renewal or comparing strata insurance quotes, committees may find it helpful to work through the following questions:

• When was the last professional replacement cost valuation completed?
• Does the sum insured include allowances for demolition, debris removal, professional fees and cost escalation?
• Have recent building works, defect repairs or upgrades changed the reinstatement cost?
• Are shared facilities, plant and common property assets properly reflected?
• Does the policy include any sub-limits or exclusions that could affect a major claim?
• Are there underinsurance, averaging or co-insurance clauses that the committee should understand?
• Is the excess appropriate for the scheme's budget and claims history?
• Has the insurer been given accurate information about occupancy, usage and known issues?

Using professional guidance

Setting a sum insured is an important governance decision for a strata committee or owners corporation. A quantity surveyor, valuer, strata manager, insurance broker or other appropriately qualified professional may each play a role, depending on the issue being considered.

A broker can help explain how insurers may assess the scheme, what information is usually required, and how policy terms, excesses and exclusions compare. Broker involvement does not guarantee a lower premium, broader cover or insurer acceptance, but it may help the committee make a more informed decision. You can find more information through the site's brokers page.

Key takeaways

The sum insured and replacement cost valuation sit at the centre of strata insurance pricing and cover adequacy. A higher sum insured can increase premiums because it may increase the insurer's potential exposure, but a sum insured that is too low can leave owners facing shortfalls after a major loss.

A sound approach is to focus on evidence rather than assumptions. Committees should understand what the policy covers, how the sum insured was set, whether the valuation is current, and what costs may arise during demolition, approvals and rebuilding. By reviewing these issues before renewal, strata schemes can make more informed decisions about premiums, risk and protection.

Published: Saturday, 6th Dec 2025
Author: Paige Estritori