Well, hempcrete is a composite material with fibers making much less susceptible to brittle fracture compared to concrete, however concrete can withstand far more compressive strength (I believe roughly 20 times hempcrete). On that same token, say I stack 5 concrete blocks and 5 hempcrete blocks seperately on one another. Concrete is very heavy, roughly 7 times as heavy compared to an equally sized hempcrete block so hempcrete does not need to have as much compressive resistance. Also because it is light and resistant to fracture it good potential for ceiling applications. Hempcrete is also an insulator so on traditional wood frame construction it can enhance stability while providing energy savings. It also absorbs acoustic noise for an added bonus. People really try to pitch the carbon negative stuff but honestly I could care less about that as I am more interested in its nontoxicity.
I googled some hemp construction video. I think there can be some improvements in their process but it can give you a visual idea of the process.