Driven by increasing electrification, climate-induced extreme events, and rapid proliferation of distributed renewable energy (DRE), energy reliability has emerged as a critical vulnerability within Australia’s building sector. Existing sector, which dominate the national building stock, represent both a latent systemic risk and an unexploited opportunity for bolstering demand-side energy resilience. While conventional building retrofit paradigms traditionally prioritize static energy conservation or carbon reduction metrics, their capacity to fortify operational energy reliability remains fundamentally underexplored. To address this gap, this paper develops a conceptual framework evaluating how energy reliability can be dynamically enhanced through digital building retrofitting. Operationalizing core principles of reliability engineering, the study demonstrates that a reliability-based building energy management framework mitigates demand-capacity uncertainty, enhances structural resilience during extreme weather anomalies, and facilitates real-time adaptive control. Nevertheless, systemic barriers persist, notably the fragmented integration of multi-source heterogeneous data, rigid "one-size-fits-all" control logic and pronounced organizational capability deficits. Ultimately, this paper offers actionable theoretical and empirical insights for policymakers and industry stakeholders steering Australia’s transition toward a resilient net-zero built environment.