Since I'm most likely not going to be around the machine when it's working, I've also got to consider material fire safety into the mix. It's still good practice to consider fire safety regardless. 

From my research, it seems that:

• solid polycarb > multiwall polycarb > acrylic >> untreated corrugated plastic
  • I'm just not sure if solid acrylic is better or worse than multiwall polycarb

Due to that, and not liking wood for some reason, that crosses out MDF and drywall (which I think in the UK is called plasterboard). I also don't like the idea of large panes of glass.

Soundproofing research says that I want to look for heavy, non resonating materials, thus thin sheets of metal are probably not up for the task. The research also says that I want sealed gaps of air inbetween. 

Sounds like 16mm polycarb multiwall is the best option so far, but I haven't seen what 6mm solid polycarb prices are though. Anyway, for the annoyingly large printer section, my estimates are around £260. I also want to make the bottom part of the SecSavr some kind of soundproof home cinema pod instead of just where my bed is (I'm a uni student with limited space), bringing that estimate closer to the £500 area. 😬

If I do go with polycarb, it's likely going to be Opal for the printer section and Bronze for the cinema section so that I can wake up feeling like I'm already in the future. I might do a bronze door so that I can see the printer (but mainly the addressable LEDs I plan to install) but I can imagine that the whole build would look tacky. Hopefully I can get to modelling soon so that I can try different configurations out.