I bet they're loving the (relatively) warm greenhouse! That's not many eggs you've been getting.Way less than a dozen eggs in December.
So far in January 4 eggs from about 24 layers.
I moved my 4 Yard Hens into the Greenhouse for the winter onto a raised bed on New Year's Eve. They seem to like it and I'm sure the garden will like it in a few months too. They don't know how lucky they have it to be out of the latest storm. Had maybe an inch of snow overnite and rain yesterday made windchill almost unbearable to me.
I guess that cold where you are is affecting their laying? I've been getting 3 eggs per day from my 5 pullets. (Two of them are laying daily.) Is that because they are in their first year I wonder?