See my "cold coop" page for discussion of temperatures for chickens, whether to run a heat lamp, and what your other options are.
Technodoll, if you are at 80% humidity with heat lamps running, either you have waaaay too many chickens for the space, and/or need to install droppings boards cleaned *every morning without fail* and also change the bedding out more often, and/or have leaks/spills/wet-ground somewhere that need to be fixed. A wet coop like that is not normal or reasonable, and should be TOTALLY FIXABLE if you go after it. Which'd be a good idea because you're likely to run into trouble if it stays that way.
Good luck, have fun,
Pat