Giving Security in Construction Contracts

It is not uncommon in construction contracts for a principal or even a head contractor to insist on security from a contractor or subcontractor. We discuss below the purpose of the security, the different types of security commonly given and what happens when a call on a security is made.

Why is ‘security’ given in a construction contract?

The purpose of security is to provide the principal or head contractor with protection if the contractor or subcontractor fails to fulfil its obligations or defaults in some way on the contract. The principal or head contractor can recoup losses that arise because of the default.

The requirement for security to be provided may also be a sensible precaution for a principal, if a contractor or subcontractor is seeking pre-payment for building materials or goods (such as bathroom or kitchen fittings) that are yet to be used in the construction project.

Similarly, a contractor may be wise to insist that a principal (or head contractor in the case of a subcontractor) provides security for any payment obligations that may be owed to them. This way, the contractor can still obtain payment if the principal fails to pay what is owed. This is especially important if the principal or head contractor is what is commonly referred to as a ‘$2 company’, that is a company without any substantial assets.

Types of security

Depending on the size and scope of the contract there are a number of options that are commonly available for providing security. These include cash, bank guarantees and insurance bonds.

The simplest type of security is ‘retention money’ or a cash security. This is when a party who is paying another party under a construction contract holds a specified sum of money back from progress payment. This is usually a percentage of the amount payable, and is eventually released at practical completion of the contract or at the end of the defects liability period.

Alternatively, bank guarantees and insurance bonds may be used instead of cash. These forms of security essentially amount to types of promises by a third party to pay an amount of money when a specified event occurs. A ‘specified event’ may include such things as a default by the contractor to complete work on time, a default in payments by the principal (if the security is in favour of the contractor) or even something as simple as a demand for payment.

The advantage of bank guarantees and insurance bonds is that they do not impact as significantly on cash flow, for the party giving the guarantee, as a cash security will. However, in order to obtain a bank guarantee or bond the party providing the security is required to pay a fee to the bank or insurer and is likely, in the case of a bank guarantee, to be required to provide some kind of cash deposit or mortgage over real property or some other security.

Insurance bonds operate in a similar manner to a bank guarantee but generally only a fee for the bond is required, and there is no further security such a mortgage. The cost of the fee for an insurance bond will be determined by both the size of the security and the risk (as assessed by the insurer) of the contractor defaulting and the insurance bond being called upon by the principal.

In addition to the guarantees discussed above, a ‘parent company guarantee’ may be required by a principal if a contractor or sub-contractor is part of a wider organisation. The effect of this type of guarantee is that the parent company becomes responsible for any default by the contractor. This can include stepping in and taking over any of the contractor’s obligations in the event of a default. Ordinarily, whichever approach is adopted the liability of the parent company will be subject to an agreed cap.

Another security option is what is colloquially referred to as a ‘letter of comfort’. This type of security is less common and is generally only used when a contractor is not an Australian company or individual and may be offered as evidence of financial standing. However, it is important to realise that letters of comfort are not the same as a bank guarantee or an insurance bond. A letter of comfort may not necessarily give rise to an immediately enforceable legal right on the part of the recipient of the letter and should be treated with considerable caution and care.

What happens when a call on security is made?

Even if unconditional security is given, it is likely that a contract will stipulate restrictions on when the security is able to be called on. Often a contract will be drafted in such a way that calling on a security involves multiple steps. For example, it is usual that the principal will firstly need to show that they have an entitlement to call on the security. Secondly any required notice of the intention to call on the security will need to be given. Finally, any obligation to give notice within a certain period of time needs to be met.

Can a contractor stop a principal from calling on a security?

It is possible to commence court proceedings seeking an order for injunction, to prevent a principal from calling on a security. However, it can often be difficult to obtain orders granting such an injunction unless certain pre-existing conditions are satisfied. These conditions may include that the contract provides for a restriction on the right to call on the security and that there is a genuine dispute between the parties as to whether the principal has an entitlement to claim payment or money from the contractor or subcontractor.

In addition, whether an injunction is granted or not may ultimately turn on the question of where the ‘balance of convenience’ lies. This will be decided by whether or not convenience dictates that the security should not be disturbed until the dispute between contractor and principal is resolved.


The giving and receiving of security is an important part of construction contracts. However, it is important that all parties to the contract understand the scope of the security and any limitations that are imposed on the parties by the contract in relation to both providing, and calling on a security. This understanding is vital for avoiding costly misunderstandings and potential litigation.

If you are considering entering into a contract that provides for security we recommend you seek legal advice before agreeing to any security provisions. We would be happy to discuss the implications of providing or receiving a security with you.

If you or someone you know wants more information or needs help or advice, please contact us on +61 2 9248 3450 or email