
SPI
Technology
Selective Paste Intrusion, or SPI, is a novel method for 3D concrete printing that was first used at Scawo3D in 2022. Today, we invent, advance and produce SPI technology for and with you.
Our SPI technology applies cement paste onto loose aggregate beds through automated print heads. This approach completely eliminates formworks whilst achieving structural integrity and surface quality across all sorts of applications – from design through architectural and structural components.
The layer-by-layer construction process deposits cement paste, creating intrusion patterns that bond with underlying materials. Each layer builds upon the previous foundation, enabling complex geometries whilst maintaining dimensional stability throughout the manufacturing cycle.
Post-printing procedures involve removal from the particle bed followed by curing under controlled conditions. Components undergo cleaning processes to reveal surface characteristics, with finishing treatments available depending on application requirements and environmental exposure.
The manufacturing process accommodates diverse component sizes within our print chamber, handling everything from decorative elements to structural components. Production scheduling adapts to project timelines whilst maintaining consistent output standards across all manufactured elements throughout the fabrication process.
Our SPI facility
Since 2022, our large format SPI facility is operational. The SPI printer itself features a particle bed measuring 4 x 2.5 x 1.5 m³ allowing for the production of architectural-scale components. Multiple silos store different aggregates, filling the particle bed, as well as different cement types that are fed automatically to the cement mixer and printhead.






Step by Step
1. 3D File Preparation

a) 3D modelling

b) Slicing

c) Particle bed arrangement
2. Selective Paste Intrusion

a) Dry particle bed

b) Application of cement paste

c) Aggregate layer
3. Unpacking & Finishing

a) Unpacking

b) Retrieval & cleaning

c) Finishing
Materials
SPI material mixtures are highly flexible and capable of featuring a multitude of aggregate and cement types. Choose from our catalog of tested materials or configure your own mixture with our help.

Lightweight expanded clay

Quartz sand
Are you interested in a specific material or in developing your own? Let us know!
Our machines are tailored to your production's requirements. Get in touch to start specifiying!
Bold ideas deserve bold solutions. We turn your vision into concrete reality.
Is your stair design too complex for conventional production? Get in touch!
Get in touch with us to print your file in 3D concrete.