Sources of Heat Loss: 35% Walls, 25% Windows, 25% Attic, 15% Basement

Heat is lost or gained in various ways from a home, and every home is different. Generally, on unrenovated homes, 35% of a home’s heat dissipates through walls, 25% through windows and doors, another 25% through the attic and finally 15% through the basement. It is for this reason that money is best spent on insulating your walls before other renovations.

An 80%-90% reduction in heat lost through walls (which isn’t at all uncommon with EIFS) results in 25-30% overall energy savings, more than 100% of windows/doors or the attic! Compare this to a 70-80% reduction you might see in replacing your windows and it’s obvious where your money is going to make the most difference.