Essential Guide

Protecting the unprotected – Interim Heritage Orders

WRITTEN BY Bruce Chalmers & Tomas Bush

This essential guide will assist local councils with the making of Interim Heritage Orders (IHOs) under the Heritage Act 1977 (the Act).[1]

What is an IHO?

Occasionally, local councils will be faced with a situation where an item that has potential heritage significance, but which is not listed as a heritage item on the State Heritage Register or under its Local Environmental Plan (LEP), is at imminent risk of harm as a result of planned development or some other activity. In these circumstances, a council may wish to make an IHO under s.25(2) of the Act.

The primary objective of an IHO is to provide time to enable investigation of the heritage values of an item and to allow for listing on an appropriate register, in circumstances where the item meets the necessary threshold test for listing at a local or State level.[2]

An IHO will temporarily protect the item from being harmed while investigations can be undertaken to determine the extent of its heritage significance and whether it should be listed as a heritage item. While in force, an IHO prohibits a range of activities that may harm the item to which it relates[3], including demolition, alteration, and carrying out development on the land on which the item is located. An IHO made by a council will lapse after 6 months unless the council passes a resolution to either list the item as a heritage item in its LEP (for items found to have local heritage significance), or to make a recommendation to the Heritage Council to list the item on the State heritage register (for items considered to have State heritage significance).

Process for making an IHO

Local councils are authorised to make an IHO under the Ministerial Order published in the Government Gazette on 12 July 2013 (Ministerial Order). When making an IHO, a council must exercise its power strictly in accordance with the conditions prescribed in Schedule 2 of the Ministerial Order (the Schedule).  A failure to do so can lead to invalidity of an IHO, and may result in an adverse costs order against the council if the IHO is challenged and found to be invalid.[4]

Preliminary heritage assessment report

While all the conditions in the Schedule must be complied with in the making of an IHO, a key requirement is that a council must consider a preliminary heritage assessment prepared by a person with appropriate heritage knowledge, skills and experience employed or retained by the council prior to making the IHO.   The preliminary assessment must address whether:

(i) the item is or is likely to be found, on further inquiry and investigation, to be of local heritage significance;  and

(ii) the item is being or is likely to be harmed; and  

(iii) the proposed IHO is confined to the item determined as being under threat.

A council must find that each of those requirements are met, based on the preliminary assessment, before it makes the IHO. If the preliminary assessment is subsequently found to be inadequate in material respect then the council’s decision to make the IHO may be susceptible to legal challenge.

Other limitations on the Council making an IHO

In addition to the above, there are other important limitations in the Ministerial Order which must be observed. In summary, the Council cannot make an IHO over an item where:  

  • it doesn’t have a heritage schedule in its LEP derived from a heritage study;
  • the item is already listed as a heritage item, or is within a heritage conservation area;
  • the item is covered by an order made under s. 136 of the Heritage Act;
  •  an IHO has been placed on the item previously;
  • a development consent (other than a complying development certificate) has been granted authorising that the item can be harmed;
  • if the item is a dwelling, a complying development certificate has been issued for its demolition and the erection of a new 1 or 2 storey house;
  •  the item is located on Crown Land, Land being developed by the Crown, or which is subject to development for which the Minister for Planning is the Consent Authority; and
  • another approval has been given by the Crown that requires or authorises the item to be harmed.

If a council issues an IHO contrary to these limitations, it may lead to the IHO being found to be invalid. For example, in Twynam Investments Pty Ltd v Goulburn Mulwaree Council (Twynam),[5] the Court found an IHO made by the Council was invalid because a previous consent had been granted which authorised the harming of the item. The Court in Twynam found that ‘had the existence of that consent properly been brought to the attention of the Council … the inevitable consequence must have been that the Council could not exercise the power to make the IHO’.[6] Twynam illustrates the importance of carefully considering the consequences of granting consent to development on potential heritage items and having an organised register of development consents.


A council is not required to give notice of its intention to make an IHO.[7] This is intended to mitigate the risk of a person urgently taking steps to harm the item before the IHO is made.

Once the IHO has been made, a council must take the following steps to notify the decision:[8] 

  • cause the IHO to be published in the Gazette, at which point the IHO will take effect;[9] 
  • as soon as possible after the Order is published in the Gazette, give notice of the making of the IHO to the Chairperson of the Heritage Council;
  • as soon as possible after the Order is published in the Gazette, give notice of the making of the IHO to each person who appears to be an affected owner or occupier. The Notice to the affected owner or occupier is to include a statement as to the effect of the order and a statement of the reasons for the making of the Order; and 
  • within 7 days after the Order is published in the Gazette, publish a notice of the making of the Order in a manner that the Council is satisfied is likely to bring the notice to the attention of members of the public in the area in which the item is situated.

Appeal rights

An owner affected by an IHO may, within 28 days of the notice being published in the Government Gazette;[10] lodge a merits appeal in the Land and Environment Court against the making of an IHO by a council.[11] 

The role of the Court in an appeal of this nature was discussed in Forte Construction Group Pty Ltd v Inner West Council (Forte).[12] In summary, Commissioner Gray in Forte said that, on appeal of an IHO, the Court will not just consider whether the “status quo” should be preserved pending the carrying out of further heritage investigations. Rather, the Court will re-exercise the functions of the Council and determine whether the item is in fact of heritage significance if sufficient enquiries have been made at the time of the hearing to enable such a determination to be made. If the Court finds that the item is not of heritage significance, the IHO will be revoked. If the Court finds that the item is of heritage significance or further investigations are necessary to determine that question, the IHO will remain in force.


IHOs can be a useful tool for councils where it is concerned that an item of potential heritage significance is, or is about to be, harmed.

Given that the issue of an IHO can have significant impacts on a person’s right to develop their land, councils should, however, be prepared to defend their decision to make an IHO in court if required. 

For more information on IHO’s, please contact our Planning, Environment & Local Government team.

[1] Where the Council is authorised by Ministerial Order Published in the Government Gazette on 12 July 2013.

[2] Byron Ventilink Pty Limited v Byron Shire Council [2005] NSWLEC 395 at [56].

[3] Heritage Act, s 57(1).

[4] Twynam Investments Pty Ltd v Goulburn Mulwaree Council [2021] NSWLEC 7 at [60].

[5] [2021] NSWLEC 7.

[6] Ibid [56].

[7] Heritage Act, s 26.

[8] Heritage Act, s 28.

[9] Heritage Act, s 29(1)

[10] Heritage Act, s 30(2).

[11] Heritage Act, s 30(1).

[12] [2018] NSWLEC 1400 at [7] – [28].

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