Anyone use straw as flooring?

Its getting colder so I have bought the buns some straw as well as their huge bail of weekly hay. My set up consists of a big insulated 6x4 dog kennel for the big bad girls with large run [20x6] split in two with a forsham giant. They all have access to interior wooden sleep boxes lined with vet bed.

The run is laid out on concrete slabs, three walls are solid wood with a double lined anti-fox /hawks weld mesh running across the whole fo the fourth. The roof is insulated and waterproof and the mesh is covered so the inside stays dry from rain. The buns loved lying across the floor during the summer but are now spending far more of their time in their kennel/hutch. Giving them garden time would be unwise given the wildlife my garden attracts so I am trying to make the run a bit more fun to be in. They have toys, hidey holes and tunnels but they are not using them now its gone dark cold and damp outside.

I am hoping the straw might make the floor a bit warmer and more fun to explore and run on BUT I have absolutely no idea how often I would need to scrape out and completely change the floor covering for them if I do put the straw down. Would it possibly attract the teeny woodmice able to get through the mesh?

Holds hand up I admit it since Pumpkin died so unexpectedly I am doing all I can to make sure Treacle is eating, snug and active and the big bad girls do more than just eat the winter away and they are safe from predators.

I do currently. My 2 are housed in a playhouse with multiple levels. They spend almost all their time on the uppermost level. I still straw the bottom to keep the chill at bay but was only saying to hubby earlier that I was going to look into other options as I am having to scrape out the straw often where it gets wet and muddy. I'm wondering if I could put some kind of insulation down, board over and then put some wipeable flooring down. Would stop straw from being strewn all about the garden (they are free range buns) and I could mop up any dampness if it rains while the shed door is open.

I don't use straw, I've got rubber floor in the shed, and in the run I use playbark from Wickes. Has to be playbark not ornamental bark as the ornamental stuff is treated with chemicals/ could have sharp edges, whereas playbark is meant for kids who might even eat it! I have to top it up a couple of times a year maximum. I think I used about 4/5 bags initially :?
(run is 10ftx17ft)

We use tons and tons of straw (literally!). Over winter we buy a bale for each enclosure and leave it as a bale at first and they sit on it, nibble it, burrow into it , hop on/off it etc etc and it acts as a windbreak and shelter. Then over the next few weeks we split chunks off it and scatter on the floor until the whole thing has gone on the floor along with the hay etc which is already on the floor (they also have tons of hay to eat/sleep in/have fun in) . We spot clean so to speak every week, do a more thorough clean of the floor every fortnight - but leave bale in and any clean top straw and hay, which we use to spread on floor again, and then after a month (by which time the straw and hay are about 10-15cm cm deep) we take the whole lot out, pressure hose, and start all over again.

Our chalets are 10ft by 6ft with special flooring (designed for cattle shed walls!) , and than raised built in hutches (6ft by 3ft but permanently open) with a level above as well. Most of the time they sit on the bales - only if its very cold do they go up above the hutches or in them.

Its kind of 'deep litter' and they love it.