insulation
n. uncountablen. material used to stop heat, sound, or electricity from escaping or entering. You put it in walls to keep your house warm in winter.
n. material used to prevent the passage of heat, electricity, or sound. Often refers to the physical substance installed in buildings or the protective coating on electrical wires.
The workers are putting insulation in the attic today.
Adding extra insulation to the roof can significantly reduce your heating bills during the winter months.
Modern building regulations require high-performance insulation to ensure that new structures meet strict energy efficiency standards and minimize their carbon footprint.
From insulate + -ion.
Uncountable when referring to the material or the state of being protected; can be countable when referring to specific types of insulating materials.