minimass™: low-carbon, low-cost, 3d printed concrete beams for the construction industry

the mission: minimum construction for maximum development

conventional beam
minimass™ beam


reduction in concrete vs conventional concrete beam

examples printed at cobod international in copenhagen, denmark

patented in the uk, minimass™ uses a relatively new manufacturing technique – 3d printing of concrete – in an innovative way, allowing the concrete to be placed precisely, without complicated or expensive formwork


reduction in embodied carbon


reduction in material costs


reduction in truck deliveries

minimass™ is the logical evolution of a design philosophy: use the right material, in the right place, for the right purpose – no more, no less

minimass™ is a new prefabricated concrete beam which replaces any other type of structural beam. 3d printing is used to precisely place the concrete in compression, with no waste, and then steel is positioned in tension.

minimass™ beams deliver up to 70% less embodied carbon, up to 50% lower material cost, and up to 35% lower supply cost compared to concrete or steel beams for equivalent performance and proportions.

11% of global carbon emissions come from construction, rising to 39% for the built environment as a whole including operational emissions [International Energy Association, 2019 Global Status Report for Buildings and Construction].

In order to reach Net Zero by 2050, the roadmap for the construction industry, from the Global Cement and Concrete Association (GCCA), requires a 25% reduction in emissions by 2030, compared to 2020.

minimass™ is the first product to realise the full potential of 3d printing for creating structural components. Sustainable development in the 21st century must include concrete solutions, but there is no need to wait until 2030 for meaningful reductions in embodied carbon. minimass™ provides savings of up to 70% – today. 

minimass™ has been designed to replace any other type of beam. This means it is relevant for both large buildings (e.g. industrial, offices, retail, education) and bridge applications. The geometry allows easy integration of services within the depth of the beam.

Examples of possible uses are:

· beams to support precast concrete floors e.g. hollowcore
· beams to support CLT slabs, to increase the size of the column grid
· long-span roof beams e.g. for industrial buildings
· long-span floor beams e.g. in airports with 18m+ grids

minimass™ was created by Andy Coward, Founder & CEO of the company Net Zero Projects Limited.

Andy holds a 1st class degree in Civil and Structural Engineering from University of Cambridge and has 20 years’ industry experience in design and construction. Prior to inventing minimass, he was Director of Engineering at Bjarke Ingels Group in Copenhagen, and Associate Partner at Foster + Partners in London.

Notable projects include:

· Tocumen International Airport, Panama
· the Orb at Burning Man festival, Nevada USA
· L’Ombriére, Marseille Vieux Port, France
· Health Pavilion, Cleveland USA
· Spartak Moscow football stadium, Russia
· Apple Stores, global.

Sarah Blake joined the business in September 2023 as Commercial Director & Co-founder. Sarah brings 11 years’ commercial real estate experience across several roles at British Land (including insights, business development & CRM), where she was part of the senior leadership team.

Prior to this, she spent four years as a strategy consultant and two in commercial & analytical roles in the FMCG and retail industries. She holds a degree in Natural Sciences & Management Studies from the University of Cambridge.

Andy and Sarah are supported by a highly experienced team of Non-Executive Directors and advisors, who bring both technical and commercial expertise to the business. This includes Chair Darran Messem, an experienced company director and NED with extensive ESG, governance, business development, sales and marketing expertise in transport, energy and the built environment.

minimass™ is a concrete and steel truss which creates stiffness and strength through axial compression and tension, not typical bending and shear, using a similar approach seen elsewhere, such as the Pont du Truc de la Fare, in France.

Pont du Truc de la Fare, designed by Michel Virlogeux and SETRA. Image by: MOSSOT

The patented geometry means that the top chord takes compression, the webs take compression and the bottom chord takes tension. The design approach uses graphic statics, inspired by the great engineers of the past. Standard design code methods, such as Eurocode 2 or ACI 318, are used to validate the strength and stiffness in the usual way.

graphic statics: geometry according to applied loads

By forcing the concrete to remain in compression, it can be designed as unreinforced, vastly reducing the quantity of steel required.

These beams could be made using traditional methods e.g. pouring concrete into formwork. However, most structural elements are not standard components, and the new technique of 3d printing unlocks the potential of this design by allowing the fabrication of any number of bespoke beams at a fraction of the cost of traditional means - mass customisation.

· No formwork
· Minimal steel reinforcement
· Reduced labour costs
· Infinite scalability

The tension capacity is provided by standard post-tensioning steel cables, with standard post-tensioning anchors.

Simple details and standard components make this a robust design.

The magic behind minimass™

A series of 6m long physical prototypes have been printed and assembled for destructive load testing.

printing the prototypes for mm-01 (unreinforced)

Working with a range of industry leaders, this testing process has been essential to validate minimass™ for the construction industry.

preparing to stress the cables

Destructive testing has been taking place using a 4-point bending test, with strain and displacement measurement throughout.

4 point bending test for the second prototype beam

Contributors: COBOD International, CCL Scandinavia, PEIKKO, SIKA, Danish Technical University

For a full range of technical details, or to discuss how minimass™ might sit within a wider project context, please contact us.

However, there are some key considerations which all designers, clients and contractors must consider:


integrated intumescent material
grouted ducts
applied insulation

The concrete is fire resistant in the usual way. The steel cables are external to the concrete, so require a project-specific fire protection solution, with examples shown in the three images.


Beams in buildings are often required to resist forces associated with robustness or diaphragm effects. minimass™ provides the same effect by using the tension capacity of the steel cables. Horizontal tie force details at beam connections are available upon request.


Being similar to a ‘T-beam’ in cross-section, minimass™ has a lower torsional capacity compared to a large rectangular beam. Therefore, the beam requires top flange restraint from connecting structure, such as a slab. During construction, it is necessary to provide temporary propping.

A torsion-resistant variation of minimass™ is currently under development.

minimass™ is a design and manufacturing solution. It is not limited in the choice of materials, nor by the manufacturing process - if sufficient identical elements are required, pre-casting is an option.

Concrete for 3d printing and beyond is a rapidly evolving field, with companies competing to produce stronger, cheaper materials with lower carbon emissions. minimass™ is leading the way, combining design, manufacture and materials to target net zero structural elements, and is future-proofed to work with low carbon materials.

UK patent granted: GB 2591831; ‘A structural truss, assembly and method of manufacture’.

UK patent granted: GB 2591905; ‘A structural truss, assembly and method of manufacture’.

Patent insurance is in place, for the protection of our intellectual property.

Patents are being extended to the EU, US, Canada and Australia.

External recognition & awards include:

· Winner of the Simmons + Simmons GreenTech Fund 2024, winning £25K of free legal advice. The Fund aims to encourage innovative solutions from around the world tackling the climate and biodiversity crises. See more about the fund here.

· 2nd place at the Innovation World Cup Smart Buildings Smart Construction in November 2023.

· Winner of the Build Offsite Innovation Challenge at UK Construction Week in October 2023.

· Technical paper published in Structures, the research journal of The Institute of Structural Engineers in December 2023.

· Letters of intent from five key industry players: Ballymore, Whitby Wood, Elliott Wood, BIG and Heyne Tillett Steel.

We are ready for pilot projects of all sizes, so we’d love to hear from you.

For more information, contact:

LinkedIn: @minimass