The main material for winter clothing in Scandinavia was wool. People who had to travel would wear several layers, including arm and leg wrappings, mittens, and a cloak. Add the tunic, and that means there are 3-4 layers of wool all over someone's body. For status, these could be dyed numerous colors; in winter 1252, Gizurr Thorvaldsson went on a murder-spree across Northern Iceland, and Sturlunga saga describes him wearing a hat, mittens, and a bright blue cloak. His enemies (or at least the ones who escaped) wound up with frostbite from having to flee into the cold with no gear.

The other main way of keeping warm in medieval Scandinavia was to not go outside! Going outside in blizzard conditions was extremely dangerous no matter the amount of clothing you wore, and only the very brave or very foolish did. Grettis saga is full of examples of both; the shepherd Glamr died (and became a revenant) by going to care for the sheep in a blizzard on Christmas Eve. There was also a monster, but only its footprint is ever seen, and Glamr's corpse is frozen solid. Grettir himself also ends up outside in a blizzard in Norway, and ends up being mistaken for a monster because the ice is so thick on his clothes. Grettir thaws out by setting the farm that mistook him for a monster on fire. In a more historical saga, Bishop Gudmundr once led a group of his retainers straight into a blizzard trying to climb Arnarnesheidi, and those who could not find a farmhouse wound up dying of exposure.

The farmhouses, in contrast, would have quite a lot of people, with the owners, tenant farmers, and slaves, and the livestock would be brought into a connected part of the house for the winter. Add the fire and it would be cramped and smelly, but actually pretty warm.