This list contains only the countries for which job offers have been published in the selected language (e.g., in the French version, only job offers written in French are displayed, and in the English version, only those in English).
At Cocoon, we’re developing low-carbon construction materials for the builders of tomorrow. Steel and cement account for nearly 15% of global CO₂ emissions, and decarbonising these industries requires completely new approaches to mix design, testing, and implementation. We’re now building our in-house concrete capability so we can qualify SCMs, validate performance against industry standards, and support deployment of our technology at pilot and demo-scale. To do this, we’re establishing a fully equipped concrete laboratory in London — and we’re looking for a Concrete Technologist to help make it happen. This role is hands-on, varied, and central to Cocoon’s ability to qualify SCMs, validate performance, and scale towards real-world deployment.
Job Responsibility:
Develop concrete mix formulations across the experimental matrix (SCM replacement, admixtures, w/b ratios) to ASTM C1709 and BSI Flex 350
Plan batching schedules, specimen numbers, test timelines, and weekly execution plans
Optimise mix proportions and troubleshoot workability, flash setting, segregation, and strength issues
Operate the mixer and conduct fresh property tests (slump, density, air content, bleeding)
Record batch data (temperature, timings, slump, w/b) and maintain full QA/traceability
Cast cubes and cylinders
manage curing tanks, curing regimes, and specimen conditioning
Perform compressive and flexural strength testing at 7, 28, and long-term ages
Prepare and run durability tests (RCPT, bulk resistivity, water absorption, sorptivity, permeability, drying shrinkage, sulfate resistance, carbonation depth)
Write SOPs for all concrete lab processes and commission existing equipment
Identify, procure, and install the missing equipment required for the testing regime
Conduct baselining exercises for cement and industry incumbents
Maintain calibration, servicing, and safe operation of all equipment
Manage consumables (PPE, mould oil, aggregates, cement) and keep the lab organised and compliant
Ensure all risk assessments are in place and adhered to
Maintain digital logs, record raw data, and align outputs with current data storage methods
Process and analyse test results
prepare technical reports and summaries, and present data for internal reviews, meetings, and partner updates
Advise on SCM qualification routes and recommend workflow improvements
Train team members in SOPs, mixing, fresh testing, and equipment use
Coordinate outsourcing for tests not done in-house and manage samples, logistics, and external data integration
Support small-scale field trials and demonstration pours, including onsite testing
Requirements:
Hands-on experience in concrete testing, materials laboratories, or construction materials research
Confident working to ASTM, BS EN, and other standards
Enjoy practical, repetitive experimental work and take pride in process discipline
Communicate clearly and maintain rigorous documentation
Thrive in a fast-moving environment with changing priorities
Proactive, organised, and comfortable owning a lab space