I have tried many different floors and here is my favorite.
When it comes to loft design, what works best for a given fancier is something that meets their own personal requirements and works in their particular climate. There are some aspects though that I believe are universally required - no drafts, good ventilation, plenty of space and dry.
My loft is in Central California. We have hot summers and wet winters with strong winds. I work long hours outside of the loft and so I can’t scrap the loft every day. These are some of the factors which shaped my requirements for the “ideal floor” for my situation:
Keeps the birds reasonably clean and out of the droppings
Gives the loft manager the option to clean at the frequency that suits their situation - even monthly if that is the case.
Does not promote drafts