Technical Lead – Thermal Modelling / Building Physics

Heatflux; Bristol; Hybrid; GBP 100,000 - 125,000; Full time

Job summary

A specialist building-physics consultancy is seeking a thermal-bridge modeller to analyze technical drawings, produce calculations, and liaise with clients. The role requires strong FEA skills and a relevant degree in building services or similar. Key benefits include flexible hours, remote work options, and professional development support. Candidates should have excellent communication skills and project management abilities. Join a small team that prioritizes work-life balance and focused technical work in Bristol.

Benefits

Flexible hours

Training and development allowance

25 days annual leave

Qualifications

• Strong experience in thermal-bridge modelling using FEA tools.
• Ability to interpret technical drawings and question their details.
• Knowledge of thermal-bridge principles and construction assemblies.

Responsibilities

• Analyse drawings and define modelling scope.
• Produce thermal-bridge calculations using FE-based techniques.
• Prepare clear technical outputs and liaise with project stakeholders.

Skills

2D and 3D thermal-bridge modelling

Strong interpersonal and communication skills

Attention to detail

CAD workflows

Project management

Education

Degree in Building Services, Mechanical Engineering, Building Physics, or Sustainability

Tools

COMSOL Multiphysics

DesignBuilder

SAP thermal-bridging inputs

Job description

Company Overview

Heatflux is a specialist building-physics consultancy focused on high-quality thermal-bridge analysis, FE-based modelling and reliable, accurate engineering. We maintain strong client relationships and continually evolve our workflows as standards change. The team is small, supportive and structured for flexibility, work–life balance and focused technical work.

The Role

• Analyse drawings, specifications and client information to define modelling scope.
• Produce 2D / 3D thermal-bridge calculations (Ψ, χ) using FE-based techniques.
• Undertake fRsi / condensation-risk assessments to ISO / EN standards and BR497.
• Prepare clear, consistent technical outputs using established templates.
• Liaise with clients, assessors, architects and design teams.
• Communicate expectations clearly and provide accurate, honest advice.
• Prepare CAD-based geometry for modelling.
• Interpret and validate complex construction details.
• Maintain and improve modelling templates and material libraries.
• Support refinement of automation workflows (Excel, CAD, reporting).
• Contribute to advanced thermal and environmental analysis capability.
• Assist adaptation of workflows to emerging standards and modelling methods.

Requirements

• Strong experience in 2D and / or 3D thermal-bridge modelling in an FEA tool.
• Degree in Building Services, Mechanical Engineering, Building Physics, Sustainability or similar.
• Strong understanding of construction assemblies and materials.
• Ability to interpret and question technical drawings.
• Knowledge of SAP thermal-bridging inputs and junction definitions.
• Confident in CAD workflows for geometry preparation.
• Strong interpersonal and communication skills with honest expectation-setting.
• Able to manage projects independently with high attention to detail.

Desirable (Not Essential)

• COMSOL Multiphysics experience.
• PHPP thermal-bridge knowledge and Passivhaus principles.
• Hygrothermal modelling experience (e.g., WUFI).
• Understanding of overheating / environmental modelling (TM59).
• Experience with dynamic simulation tools (IES VE, DesignBuilder, TAS).
• Interest in automation, scripting or AI-assisted modelling.

Benefits

• Flexible hours and hybrid / remote working.
• Option for 3, 4 or 5-day week.
• 25 days annual leave + bank holidays (pro-rata).
• Training / development allowance and professional memberships paid.

Working Environment

Bristol / South West based, with flexible hybrid working (typically 2–3 days in our Bristol co-working studio). Remote working supported once established. The environment is calm, low-bureaucracy and designed for focused technical work, with a high-trust approach and minimal micromanagement