Energy Performance of a Residential Block

fominalexanderark@gmail.com (Alexander Fomin) — Fri, 14 Aug 2026 00:00:00 +0000

Summary

Led the end-to-end Energy Performance Certification (EPC) process for a high-profile, new-construction multi-family residential building integrated with commercial office spaces. Serving as the primary technical driver, I maintained total ownership of the project workflow from initial architectural assessment and thermal zoning through to the final regulatory signing of the certificate.

Project Date: 2024

This project required a high degree of adaptability, involving the rapid self-taught mastery of specialized BIM software, navigating extensive client-side documentation delays, and executing major design revisions mid-lifecycle while strictly adhering to the Spanish Technical Building Code (CTE).

Role: Lead Project Engineer / BIM Modeler

Methodology: OpenBIM Workflow (CYPE MEP ➔ BIMserver.center ➔ CYPETHERM HE Plus)

Key Competencies

BIM & Engineering Software: CYPE MEP, CYPETHERM HE Plus, BIMserver.center, CE3X.
Regulatory Knowledge: Spanish Technical Building Code (CTE), Energy Performance Certificates (EPC/CEE).
Core Skills: Parametric thermal simulation, OpenBIM workflows, technical problem-solving, client and vendor communication, autonomous professional development.

Project Lifecycle & Technical Methodology

I established and executed a structured, multi-phase OpenBIM workflow to bridge the gap between initial architectural design and final thermal simulation:

Building Envelope Modeling: Developed the complete 3D digital twin of the building in CYPE MEP, inputting structural geometries, spaces, and thermal zones.

Systems Definition: Integrated HVAC, Domestic Hot Water (DHW), and lighting installations based on project specifications.

Cloud Synchronization: Exported the unified model to BIMserver.center, utilizing its cloud-based ecosystem to manage, share, and update project data via a licensed BIM account.

Regulatory Simulation: Imported the cloud-synchronized BIM model into CYPETHERM HE Plus (the official, Ministry-approved freeware tool) to perform official energy compliance calculations.

Engineering Challenges & Problem Solving

Mitigating Documentation & Data Gaps: The project faced a 1.5-month administrative bottleneck due to a total lack of client-provided construction specifications, carpentry schedules, and building service layouts. To maintain momentum, I proactively initiated the modeling phase using standardized, generic elements from the CYPE Price Generator (Generador de Precios), establishing a solid baseline that could be swiftly modified once finalized data arrived.
Managing Mid-Project Design Revisions: The initial floor plans provided by the client were fundamentally altered during construction. This required a comprehensive overhaul of the existing digital twin—manually re-mapping shifted layouts, re-defining internal spaces (recintos), adjusting structural units of use (unidades de uso), and re-routing the associated building services to match the final architectural reality.
Rapid Software Adaptation & Self-Guided Learning: Having no prior experience with CYPETHERM, I demonstrated rapid technical agility by mastering the platform independently. By dissecting the software’s official engineering manuals and leveraging its similarities to simplified tools like CE3X, I successfully bridged the learning curve without delaying the project timeline.

Troubleshooting & CYPE Support: Transitioning models from CYPE MEP to CYPETHERM frequently introduced complex data export anomalies. I methodically resolved critical pre-calculation errors, including domestic hot water (DHW) flow discrepancies across units of use, partition wall thermal definition issues, and unassigned installations. To bypass lengthy telephone queues, I established an efficient email-based liaison with CYPE’s technical support team to rapidly clear software-level bottlenecks.

Technical Analysis & Iterative Optimization

Successfully executing the compliance checks required a deep, fundamental understanding of the thermodynamic formulas and mathematical algorithms operating beneath the software’s user interface.

To achieve the highest possible energy rating and ensure flawless compliance with strict CTE regulations, I conducted exhaustive parametric studies. This involved running multiple simulation scenarios, testing distinct thermal transmittance values ( $U$ -values), experimenting with building envelope insulation thicknesses, and fine-tuning equipment efficiencies to drive down non-renewable primary energy consumption and $CO_2$ emissions indicators to their absolute technical minimums.

Final Results & Crisis Management

The ultimate objective of the project was fully realized, achieving a successful ‘B’ Energy Rating, exactly matching the architect’s target and design expectations.

However, securing this result required managing a critical, last-minute construction crisis. While the architect had originally specified solar thermal panel for domestic hot water (DHW), the site construction chief mistakenly procured and installed solar photovoltaic (PV) panels instead. This swap presented an immense regulatory hurdle, as the building suddenly failed to meet the strict legal minimum requirements for renewable thermal energy contribution.

To salvage the certification without tearing down the installed system, I spearheaded the technical strategy to resolve the discrepancy. I performed a rigorous, exhaustive set of compensatory thermodynamic calculations for the entire building to demonstrate equivalence.

Through precise modeling, I determined the exact deficit and negotiated the strategic purchase of additional photovoltaic panels. By offsetting the thermal shortfall with increased on-site renewable electricity generation, I successfully bypassed the regulatory bottleneck, satisfied the Spanish Technical Building Code (CTE) mandates, and delivered the targeted ‘B’ certificate.

Energy Perfomance Certification using CE3

fominalexanderark@gmail.com (Alexander Fomin) — Tue, 11 Aug 2026 00:00:00 +0000

A long while ago, as part of my graduation project for a class that I had for my Higher Diploma in Building Projects (Grado Superior en Proyectos de Edfificación, in Spanish, something like a minor degree), I had to write a manual on using a software named “CE3” for Energy Performance Certification of buildings (Certificado de Eficiencia Energetica de viviendas). It was based on the work of my professor, architect Ildefonso Bermejos Berenguer “CE3, Certificación Energética de Edificios Existentes (Residencial y PMT)”.

What is CE3 (CE3X)?

CE3 -> Calificación Energética de Edificios Existentes

It’s a software distributed for free by the Spanish government and used here for EPC of buildings. It’s the official tool of the IDAE and was developed in collaboration with CENER. EPCs are necessary for all new constructions and renovations, and also for selling or renting any property.

Official webpage of IDAE for download

The manual

It was wriitten in 2024. The manual consists of basic intructions on how to make an EPC of a residential building. It explains the regulatory context, details the specific “By Plans” (Por planos) methodology using CAD architectural drawings (.dxf files), and provides a step-by-step walkthrough of entering administrative, constructive, and systemic data into the program. Finally, it breaks down how the software calculates energy demands, final/primary energy consumption, and $CO_2$ emissions to generate an official Energy Performance Certificate and Label. It’s written in Spanish, and I won’t be translating it into English, since it’s not used outside of Spain and doing so makes no sense.

Key points:

Regulatory Compliance: According to Spain’s Technical Building Code (CTE DB-HE) and Royal Decree 390/2021.
Purpose: This specific method is used for complex buildings that generate self-shadowing or have intricate geometries.
Process: Technicians map out the building using polylines in CAD software (such as AutoCAD) to define different climate-controlled zones based on usage and orientation, then export it as a .dxf file to load into CE3
Advantages: It offers exact geometric definitions, precise calculations, accounts for self-shading, and yields highly reliable certification results.
Step-by-Step Data Input in CE3.
Technical Calculations & Results: The software processes the input data to calculate the Global Energy Efficiency Index (IEE Global). It evaluates: Energy Demand, Final vs. Primary Energy Consumption, $CO_2$ Emissions, Air Renovation & Ventilation.
Gives the Energy Certificate & Label.

Check it out or download:

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