Just got through a heat-wave here in Las Vegas. It was 117(f) / 47(c). Got through fine by adding frozen water bottles to the water along with 325mg of aspirin (not ibuprofen or acetaminophen) per 1 gallon water. I also added a fan and a mister system, and covered most of the run with an old run to block the direct sunlight. I was able to drop the temp in the run to below 100(f) / 37(c). The downside was that the misters did make the straw I had in the run damp. I had to remove the straw so the ground would dry out and to prevent the straw from molding. With these steps the hens didn't have labored breathing and continued to eat and drink as normal.