It's usually not a problem (not in SE Wales anyway), though early this year it was. Straight after Christmas and New Year, when you're chomping at the bit to get out to work and everything freezes up on you is a pain.
Even trad was impossible some days (not just early mornings).
Some properties were fine to work on, on one side, but round the back where things were in the shade or less exposed and everything would freeze up.
I remember a few days where I was determined to work but just couldn't. But its not normally like that.