Urban development and the construction industry account for a considerable proportion of global carbon dioxide (CO2) emissions. Emerging biological materials, such as those proposed in this paper, seek to utilize the metabolic functions of living microorganisms to reduce some of the negative impacts of humans on the environment. The material explorations demonstrated in this paper propose a living photosynthetic carbon capture textile for the built environment. We demonstrate making practices that integrate living microorganisms within experimental methods of digital fabrication; specifically, harnessing photosynthetic microalgae that feed on waste and are capable of sequestering CO2 from internal building settings. These new biocomposites incorporate flexible textile substrates, i.e. cotton, hessian, polyester, and canvas, which provide a range of algae laden matrices that continue to develop and change during the useful part of the material’s lifecycle. This paper explores biological 3D printing fabrication processes and studies the development of mixtures that are compatible with the fabrication method and support microalgae (Chlorella vulgaris) metabolic processes. A range of incubation methods are assessed, highlighting the need for a support environment. The biocomposites’ performance is tested using imaging pulse amplitude modulation fluorometry (Imaging-PAM) to investigate changes in microalgae chlorophyll fluorescence over a 14 day period. © 2021 Assia Stefanova et al., published by De Gruyter.