Achieving a high Energy Performance Certificate (EPC) rating for commercial properties isn’t always a straightforward task—especially in buildings where multiple tenants share centralized heating, ventilation, and air conditioning (HVAC) systems. Shared HVAC configurations introduce complexities that can significantly impact how energy efficiency is assessed and scored.
At EPCrate, we specialize in conducting EPC assessments for multi-tenant commercial properties, offering solutions to address these unique challenges.
The Problem with Shared HVAC Systems in EPC Assessments
Standard EPC software assumes a direct relationship between a property’s heating/cooling systems and its energy consumption. However, in commercial spaces like shopping centres, office complexes, and mixed-use buildings, HVAC systems are often:
Centrally managed and shared across multiple units.
Equipped with inadequate sub-metering, making it difficult to allocate precise energy usage per unit.
Operated with variable controls that differ between tenants (e.g., setpoint temperatures, operational hours).
These factors complicate how energy efficiency is evaluated during an EPC assessment.
Key EPC Assessment Challenges with Shared HVAC Systems
Default Assumptions Penalise Efficiency
When assessors lack exact data on HVAC efficiency per unit, the EPC software defaults to conservative values, which may lower the rating unnecessarily.Lack of Sub-Metering Data
Without individual energy meters, it becomes difficult to quantify how much energy a specific unit consumes, forcing the use of building-wide averages that can skew results.Difficulty Documenting Control Systems
Shared HVAC setups often lack clear documentation on zoning, thermostatic controls, or BMS (Building Management System) integrations, leading to further assessment penalties.Tenant Behaviour Isn’t Reflected
Efficient tenant behaviours (e.g., after-hours shutdowns, temperature moderation) are not accounted for, as the assessment is based on building fabric and systems, not user practices.
Solutions to Overcome Shared HVAC EPC Assessment Barriers
At EPCrate, we recommend several strategies to ensure shared HVAC systems are properly accounted for in EPC assessments:
Detailed HVAC Documentation Submission
Ensure you provide specifications for plant efficiency, zoning diagrams, and system maintenance records to support a more accurate assessment.Sub-Metering Installation (Where Possible)
For future EPC re-certifications, installing sub-metering systems allows for accurate allocation of energy use per tenant or zone.Use of Alternative Assessment Routes (SBEM Methodology)
Larger commercial premises with complex HVAC systems benefit from SBEM (Simplified Building Energy Model) assessments, which offer more flexibility than RdSAP.Bespoke System Efficiency Calculations
Engage assessors who can perform bespoke HVAC efficiency calculations rather than relying on default EPC software values.Thermal Imaging & Site Visits
Comprehensive site assessments, including thermal imaging, can help document efficiency measures that aren’t apparent in standard documentation.
Importance of Choosing an Experienced Assessor
Many commercial EPC assessments fail to reflect the building’s true efficiency due to the assessor’s lack of experience with shared system complexities. At EPCrate, our team understands:
How to model shared HVAC systems correctly.
The documentation and evidence needed to avoid conservative defaults.
How to advise landlords on energy efficiency improvements that genuinely impact EPC ratings.
Book a Commercial EPC Assessment with EPCrate
Operating a multi-tenant commercial property? Don’t let shared HVAC configurations ruin your EPC rating. Book an EPC assessment with EPCrate and ensure your building’s efficiency is accurately assessed.
Explore our pricing plans for complex commercial EPC assessments or contact us for a tailored consultation.
