I use US-05 on my IIPA sometimes, I like the results. Well, I pitched and aerated and I took off for a few days and came back to see that the auto valve on glycol unit failed and left the valve open and had crashed the beer to 45 degrees. And the US-05, while albeit slowly, was steadily fermenting.
Got it ramped up and fermenting away nicely now but pretty amazed that it would ferment at those temps. The yeast was rehydrated (see, Tom
) in about 95 degree water and I'm not exactly sure how long the lag was, but it was fermenting 2 days later at 45 degrees after pitch.
I have purposely fermented US-05 at around 54 degrees with good results before. But shocked to see it chugging along this cold. I seen some lager yeasts that struggle under 48.