absolutely miserable

Could you make a 'doormat'? Maybe a large old baking tray or seed tray or something a bit deeper - fill it with hemcore or something else absorbant and position in front of the door so they have to walk through it to get in to the coop and wipe their feet.
Or maybe a tunnel - I think I read of someone else on here who'd done that.
I'm lucky in that regard in that I've got my coop under a big old fir tree for the winter that is more or less dry. Downside is I know there are about 10 pairs of wild birds that nest in the tree...
Poor chx, sometimes I feel like bringing them in to watch telly when it's really cold and raining.

Mine are miserable as well.  We've had constant high winds and rain for days and as they have been broody lately have had to shut house, so they have been sheltering under it. At least its sitting on peagravel and on a slight slop so they arent getting flooded. It stopped raining for a while earlier on today and they were practising their flying technics in garden.  OH said it was hilarious watching them.  The upside of it is they get let into house earlier cos our clocks have done back (has anyone told them about it)?
Jinty

I've also seen an old pallet used as a walk way to the hen house. It was washed off of poop and mud each week. It certainly helped the house stay a great deal cleaner and dryer.

We put down 20mm gravel from the builders merchants a few weeks ago and it seems to be working. It's expensive at nearly £30 a tonne but can be raked, hosed, is smooth on their feet, won't hide bacteria or pests and you only buy it once. They still have chippings and sand in the dry covered area in which they dig big (dangerous to humans) holes when the weather is bad.
Last year we used pallets which were fine for a while but became slippery and unsafe after a few months.

Hi Nicky

It depends how big your run is etc but I was expecting a similar problem this winter so I got some cheap paving stones from B&Q which I put down to make a temporary 'patio'. I then place the house/run on top and am using easibed or similar as a bedding. It is relatively easy to keep clean and once a week or so you can remove all the bedding and then scrub & disinfect. It also has the advantage that it would be difficult for predators to dig their way in. Does your run have a cover?

All the best

Helen

If practical I would try and do what Debsie is proposing and cover part of your run in order to keep out the rain. Its also worth partially covering the sides as its surprising how much rain is blown into the run from the sides.

Its not always practical to do the above because of the size and design of the run. It may however be worth constructing a sheltered area within the run to provide your chickens with some cover from the rain. Pity they don't just go back in the coop during bad weather but that's chickens for you