I am trying to decide what to try for next winter. I am considering straw, shredded paper or wood chips (I recently bought a shredder).
I live in northern Minnesota. The past 2 winters I used wood chips as deep litter in the coop. That worked great. This winter I am using paper shreds I make at home and that has worked out very well for me. I have access to free wood chips and, of course, I used my paper shredder to make litter for the coop this year. So, for me, the cost of the litter - wood chips or paper shreds - was basically free.
Straw is OK, but I always found it more dusty than either the wood chips or the paper shreds. Having said that, I think most of the dust in the coop comes from the chickens themselves and not from the wood chips or paper shreds. Straw, on the other hand, was dusty off the bale. At least, the straw I got was dusty.
My coop litter - wood chips or paper shreds - gets dumped into the chicken run composting system in the spring and I let it compost for use in the garden in the fall after the harvest. Wood chips can just be thrown out into the run, but the paper shreds need to be covered with existing compost in the run or else I will have paper shreds blowing across the yard that afternoon. However, the paper shreds should compost down much faster than the wood chips. Also, I shred lots of paper and light cardboard at home just to reduce the amount of stuff that has to be sent to the recycle/landfill. My little way of being "green" that benefits both me and my chickens.
I have also used dry leaves from fall clean ups, but those tend to be more dusty and I would not recommend used dry dusty leaves if your goal is to reduce dust in the coop. I mixed my leaves in with the wood chips, and that worked OK, but like I said, I know the leaves were dusty before I put them in the coop.
The dust comes from the chickens more than from the bedding -- it's their feather dander.
Although I agree in general, I have bought dusty straw and the leaves I saved for winter use were dusty. In any case, if you have 100% dust free litter, you will still have to deal with some amount of chicken dander dust.
Interesting. So if that is the main reason for the dust, I probably won’t see a difference with different bedding.

I will experiment and see.
Yeah, well, no in my experience because you can definitely get dusty litter from the start. I found that my wood chips and shredded paper had very little dust - at least compared to the straw I used to buy and the leaves I mow up in the fall from the yard.
I am not an expert, but I don't think there is such a think as a dust free chicken coop.
I agree. Even if you had dust free litter, you would still have to deal with chicken dander dust.
I will see if it is any better with wood chips and/or straw next winter.
FWIW, in my 3 winters of having laying hens, I think the "best" coop litter for me is either free wood chips or free paper shreds. I used to buy straw, years ago, but that was expensive and I was never really happy with it as litter for the birds. I have both a large gas wood chipper and a smaller electric wood chipper that I use to make my wood chips at home from fallen branches. That is a lot of work if you think you can chip up enough wood at home for a medium sized coop. I can hitch up my trailer, go to the county landfill, and fill my trailer up in about 20 minutes. I think it might take me about 20 hours of work to chip up that much litter at home on my chippers.
I have a few paper shredders at home, and I just shred my paper products as I get them. I typically dump a bag or two of paper shreds into the coop once every ~2 weeks and that is enough to keep the litter looking clean and smelling fresh. If you already have a shredder at home, and you are shredding paper anyway, you might want to use it as litter.
Nothing says that you cannot mix and combine different types of litter. I use just about anything I can get for free and that I can compost later when I clean out the coop. I have mixed wood chips, leaves, paper shreds, and dried grass clippings in the coop and it all seems to work fine. Once I got past the notion that I had to buy straw for my coop litter, then the blinders came off and I now use just about anything and everything I can get for free. And then I compost all the used litter in the spring and throw it into the garden in the fall.
My chickens live in their coop from snow fall in November till snow melt in April. They just will not go outside with snow on the ground. So, I appreciate your efforts to reduce dust build up in the coop. Whatever you decide to use as litter next year, I hope you will start a thread and post your progress and results.