The thing is there are really
two different things that "deep litter method" can mean.
"Real Deep Litter Method" - the historical version, the one with all the many actual benefits to the animals.
This is the one where the litter starts to compost in place, providing warmth, vitamins, bugs to eat
, microbial control of some pests and diseases, etcetera.
It only works if your litter is damp enough to compost AND has a good inoculum of composting organisms -- both of which will occur automatically on an earthen floor and are unlikely to occur on cement, wood, or vinyl. You can get a little composting going on one of those non-earth surfaces by *making* the litter a little damp (be very careful with this, you don't want to be making a swamp!) and adding a few shovelsful of good garden dirt. However, from experience with horse barns I will say that this still does not produce anything like the deep-litter composting you get on a real earthen floor, and all in all I am not sure it would be worth trying.
"The Lazy, no wait - Efficient <g> Deep Litter Method" (I do this myself, so don't think I'm picking on it!) is when you do NOT have an earthen floor and have no hope of significant composting etcetera, and yet you let the litter pile up anyways because it isn't possible to just pick the poo out like you could in a horse stall and really who'd want to throw away all that perfectly good bedding when it's not bothering anybody yet
This may not have as many benefits as old-timey 'let the bedding pile up til the cows' ears are scraping the rafters' deep litter, HOWEVER it is still perfectly fine for the chickens and conserves time, energy, and bedding. I can see no reason whatsoever not to do it.
Pat