Overview
CEN ISO/TR 52018-2:2017 (ISO/TR 52018-2:2017) is a technical report that explains and justifies the partial energy performance of buildings (EPB) indicators listed in ISO 52018‑1. It focuses on indicators related to the thermal energy balance and fabric features of buildings (thermal envelope). This document is non‑normative: it provides background, rationale and practical considerations to help public authorities, regulators, designers and other stakeholders make informed choices when defining partial EPB requirements.
Key topics
The report expands on the scope and intent of ISO 52018‑1 and covers practical issues including:
- Summer and winter thermal comfort - motivations, points of attention and indicator selection.
- Energy need for heating and cooling - definitions, variants and how to compare options.
- Combination of “needs” - how different energy needs interact for meaningful indicators.
- Overall and individual thermal insulation of the thermal envelope - criteria for setting requirements and trade‑offs.
- Thermal bridges - assessment approaches, alternative routes and implications for design and regulation.
- Window energy performance - relevant indicators and considerations.
- Airtightness - role in energy balance and practical measurement/requirement issues.
- Comparable economic strictness and cost‑effectiveness considerations - guidance for assessing the economic impact of differing regulatory choices.
- New construction vs renovation and exceptions - tailored recommendations depending on building status.
The report includes symbols, definitions and structured discussion to support the uniform reporting tables presented in ISO 52018‑1.
Applications
CEN ISO/TR 52018‑2:2017 is intended for:
- Regulators and policy makers who must choose and document partial EPB requirements consistent with the EU EPBD framework.
- Energy modelers and certifiers using EPB indicators for compliance, certification or benchmarking.
- Architects, engineers and product manufacturers seeking to understand regulatory intent and practical implications for thermal envelope design (insulation, windows, airtightness, thermal bridge mitigation).
- Stakeholders in renovation and retrofit programs to evaluate how partial requirements affect intervention strategies.
Use cases include designing national/regional EPB requirement sets, preparing public consultations, and developing compliance pathways that balance thermal performance, occupant comfort and cost‑effectiveness.
Related standards
- ISO 52018‑1 - enumeration and reporting tables for partial EPB indicators (primary reference).
- EPB standard set developed under CEN mandate M/480 linked to Directive 2010/31/EU (EPBD).
- Work by ISO/TC 163 and CEN/TC 89 on thermal performance of buildings.
Keywords: energy performance of buildings, EPB, ISO 52018‑2:2017, thermal energy balance, thermal envelope, insulation, thermal bridges, airtightness.