Firewalls and Unit Titles: A Comprehensive Overview

Unit Titles Necessitate Firewalls  
For properties looking to implement separate Unit Titles, firewalls are not just recommended but required. The reasoning is foundational: the Building Act stresses the importance of "Protection of Neighbouring Properties." This act mandates that when shops or commercial spaces are segregated into separate titles, they must be compartmentalized with firewalls. However, the precise fire rating performance, which ranges from basic fire resistance to more advanced barriers, is dictated by the shop's usage and is subject to a specialized fire design assessment. 

When Firewalls Might Not Be Required  
In scenarios where properties don't opt for individual Unit Titles – say, when a property owner intends to split a large commercial space into multiple shops under one consolidated title – the necessity for firewalls often diminishes. This is largely because the structural integrity and purpose of the space remain largely unchanged, and thus the safety requirements are consistent. 

The Exceptions to the Rule  
Although the use of firewalls often ties back to the decision around unit titling, there are exceptions where firewalls are mandated, irrespective of title divisions. Some of these exceptions arise due to modifications in the building's use or design. For instance, if there's an anticipated increase in the occupancy limit or if the purpose of the space is altered (e.g., from a storage unit to a shop), firewalls might be deemed necessary. Similarly, other architectural and safety criteria like maintaining open path separation might also trigger the need for these protective barriers. 

In Conclusion: Safety First, Always  
Whether driven by legislative requirements or proactive safety measures, the incorporation or omission of firewalls in commercial properties should be a meticulously calculated decision. Property owners and developers must remain abreast of the ever-evolving safety regulations and work closely with fire safety experts to ensure the wellbeing of both their property and its occupants.