Norwegian houses were historically painted red, yellow, or white. White is the most popular color, even these days. The color the owners chose depended mostly on what they could afford.
Red: The red color was the cheapest to produce. It was created by mixing ochre with cod liver oil (or other vegetable oils or animal oils). As a result, many buildings in farming lands or fishing areas where incomes were lower than average were mostly paint in red. This is why so many barns in the country side were traditionally painted red.
Yellow: The yellow color was a little more expensive than red and was also created by mixing ochre with cod liver oil.