Renewable lightweight composite assembly

A lightweight composite architectural panel assembly, comprising:

• a) one or more first end joists and one or more second end joists spaced parallelly along a perimeter of the assembly, each having a length;
• b) one or more web plates spaced parallelly between the end joists;
• one or more first upper surfaces arranged at a first distance to one or more lower surfaces;
• and attached to the first end joist, the second end joist, and the web plate, forming one or more channels disposed vertically between the upper surface and the lower surface and longitudinally extending along the first upper surface and the first lower surface, thereby forming an open-ended boxlike body;
• and
• c) a structural vertically load-bearing sheathing layer enveloping and adherent to an outer surface of the open-ended boxlike body, wherein the sheathing layer comprises a composite skin comprising a fibre mesh and a crosslinked polymeric resin system,
• wherein the polymeric resin system comprises Polyfurfuryl Alcohol (PFA) resins and curing or crosslinking agents.