The feasibility of a sustainable non-autoclaved cellular concrete, based on flax vegetable co-products, for the pro- duction of usable specimen in the lightweight construction field, has been investigated experimentally. The pro- duced specimen, containing various volume ratios of flax particles with respect to preformulatd Tradical PF70 lime binder of 0, 1, and 2, were lightened by creating a porous structure in the matrix through the addition of 0.3% wt. Aluminium powder (able to react with calcium hydroxide from the binder and result in microscopic air-bubbles). Fresh and hardened specimen properties, including hydration, fresh density, porosity, hardened den- sity, compressive and flexural strengths, toughness energy, and dry thermal conductivity at different temperatures, were assessed for varying flax-to-binder ratios. Results have shown that the addition of Aluminum powder leads to restrain the setting time delay of binder-based lime. Moreover, the hardened material displays a significant decrease in specimen density, thereby resulting in a compressive strength level compatible with that required in the cellular construction materials sector. Results also highlighted the ability of added flax to induce a change in the specimen from brittle to ductile behavior. Moreover, a high degree of thermal insulation can be achieved, which makes the cellular specimen based on flax particle suitable as insulated-bearing walls material.