Heat is sometimes lost from a house through cracks around windows and doors. Radiation implies that an object is glowing. Clothes catch some of that radiation and keep you warmer. Conduction describes the flow of energy through a material rather than the flow of the material. This is how heat gets from the stove to the pot and from the pot to the water.
Convection describes the flow of the material as it spreads the warmth.
Since the cracks let warm air escape, heat is out of the house.