Cement and Concrete Development Engineer (m/f/x)

Berlin

Kalz GmbH i.G.

About Kalz

We are a mineral carbonation startup that stores CO2 in industrial wastes, recycled concrete, and selected primary materials, turning them into low-carbon construction materials. We are now looking for a Cement and Concrete Development Engineer to lead the development, testing, and validation of cement blends based on our mineral carbonation products.

The Role

As a Cement and Concrete Development Engineer, you will own the technical development pathway from carbonated reactor output to concrete-ready product. You will build up our lab and testing facility, design and execute testing programmes, develop SCM and cement blend formulations, evaluate performance across different cement systems, and help develop and validate our materials for industrial deployment.

This is a hands-on technical role at the interface of cement chemistry, concrete technology, materials testing, product development, certification, and customer validation. You will work directly with the founding team and play a central role in defining how our mineralised products are used in real concrete applications.

As a startup, priorities may evolve quickly. We are looking for someone who enjoys building new capabilities, working across disciplines, and helping shape the direction of the company.

Responsibilities

• Develop SCM blends using carbonated materials from Kalz’s mineral carbonation reactor.
• Plan and conduct a range of tests for strength development, workability, durability, CO₂ reduction, cost, and market applicability.
• Design cement, mortar, and concrete formulations across different CEM types and binder systems.
• Support the development of certification, standardization, and market approval strategies for new cementitious materials.
• Measure and evaluate relevant material properties, including compressive strength, flexural strength, setting behaviour, workability, water demand, density, heat development, durability, and long-term performance.
• Plan and coordinate advanced characterisation where relevant, such as particle size analysis, XRD, TGA, SEM, BET, chemical analysis, and reactivity testing.
• Assess relevant cement and concrete standards and identify certification pathways.
• Support external testing, third-party validation, and customer trials with cement and concrete producers.

Desired experience and skills

• Degree in civil engineering, materials science, chemical engineering, mineral processing, or a related field
• Practical experience with cement, mortar, concrete, SCMs, binders, or construction materials.
• Ability to take ownership of a product development programme in a fast-moving startup environment.
• Strong understanding of concrete mix design, cement hydration, strength development, and durability.
• Familiarity with material characterisation techniques such as XRD, TGA, SEM, particle size analysis, BET, or chemical analysis.
• Strong analytical skills and the ability to connect material properties to product performance.
• Clear communication and documentation skills.
• Ability to work independently, make decisions under uncertainty, and prioritise experiments based on product development goals.

We recognise that relevant experience can be gained in academia, industry, startups, consulting, testing laboratories, or other technical environments. We welcome candidates from different professional backgrounds who are excited about developing low-carbon construction materials.

What We Offer

A central role in a climate-tech startup with significant ownership, and real-world industrial relevance in Berlin. We are committed to creating an inclusive, diverse, and respectful workplace where everyone can thrive. We welcome applicants regardless of gender identity, nationality, ethnic background, religion, disability, age, sexual orientation, or life experience.

Application

We also know that strong candidates do not always meet every requirement listed in a job description. If this role excites you and you believe you could contribute to Kalz, we encourage you to apply even if your background does not match every point perfectly.

Please send your CV and/or a short note explaining your experience with cement, concrete, SCMs, or construction materials to: jason.collis@kalz.tech