No frost! Esp. when they've got some growth. It'll turn the leaves to something resembling cooked spinach- yuck. Move out the furniture- then you'll have more room for your dahlias :)
Ellie

Hey there Dahlia Gardener, I am laughing at your suggestion! And, considering it just a little. I started a bunch of Cannas, some of which turned out to be Dahlias, that I had been given. Never having started bulbs or tubers in my home, I am shocked at the growth and how much space they are using up! I have barely been able to get any seeds started. Thanks for your answer on the frost!

Ellie, my dahlias got nipped by frost on their very small tips, the new growth seems to be OK but has the frost damaged future flowers or anything? Thanks for any input. Kat

Kitkat- they'll come back fine if they were just nipped on the tips. Your blooms might be one flower late but not more than topping would have done. You were lucky that the frost wasn't a hard one that would mush up all the new growth but even then, if the tuber doesn't freeze the plant will usually start growing all over again but blooming is set back every time you lose new growth.
Ellie