My apiary is less than half a mile from the sea which gives such a moderating influence on temperature that settling snow is unusual and the ground rarely stays frozen beyond a few days each winter. When the roof of each of my hives was constructed a slab of insulation board was included below the metal sheet [one copper, the other two stainless steel].* To the northward [seaward] side of the apiary is a disused railway embankment some 3m high, overgrown with mainly sycamores and the site is in a bowl - but not acting as a frost hollow. Cosy.
I'm in agreement with jenkinsbrynmair and BeeKeyPlayer on this.
*My hives were made by my neighbour whose last job was as a stainless steel fabricator. Access to scrap was no problem - hence the roof material AND my hive tools. The copper was half of an old hot water tank - he cut it in two and completed one roof, but wandering thieves stole the other half from his driveway whilst he was eating his dinner! As I mentioned elsewhere, this lovely gentleman gave me all his beekeeping kit when he ceased to keep bees.
Yes, I have capacity for 3 hives, but recently-imposed allotment rules restrict me to 4 in total. As I have a couple of nucs which get used, the "spare" hive kit is mainly as a reserve. The thought has occurred to me, that as my landlord is very ignorant about beekeeping I could piggyback a second colony above a crownboard and have the entrance facing transversely. The desire/need for that has not yet arisen.