History of Insulation Used in Attics

Striving for ideal attic insulation has been a quest undertaken by humans for generations. A look at the history of insulation used in attics and elsewhere in houses and other structures provides insights into the evolution of products designed to protect people against the elements.

Ancient Civilizations and Insulation

Insulation has a long, storied history. Insulation was first used by Viking and Egyptian civilizations thousands of years ago. Vikings incorporated mud and straw in between logs used to build homes as a means of insulating. Egyptians made bricks of mud that served multiple purposes, including insulation.

Ancient Greece was the first civilization to utilize a type of insulation that was used into the 20th and 21st century: asbestos. Ancient Greeks were convinced that asbestos possessed magical qualities because it is fire resistant. Indeed, the word “asbestos” is Greek for “inextinguishable.”

Middle Ages

Insulation practices that were widely used in ancient civilizations were broadly abandoned in the Middle Ages. In the Middle Ages, the typical home in much of the so-called known world was made from stone with thatched roofs. As a consequence, these structures tended to be drafty, cold, and damp. In response, people hung tapestries in an attempted to insulate a home.

Industrial Revolution

It was during the Industrial Revolution that specific products were created to provide insulation in homes and buildings of all other types. Oftentimes, these insulation products were comprised of asbestos. Asbestos insulation became widely used in attics and between walls. In addition, it was used to wrap pipes that carried steam for heat throughout buildings and between these structures and a local steam plant.

The 1930s and 1940s

A major revolution in home insulation occurred during the 1930s and 1940s. During this era, fiberglass insulation came into being. The introduction of fiberglass into insulation was considered a major breakthrough.

As happens with considerable regularity, fiberglass came about by accident. A scientist named Dale Kleist was attempting to create a vacuum seal between two blocks made of glass. The high-pressure air stream that inadvertently developed during this process ended up turning some of the glass blocks into thin fibers. Ultimately, these fibers became the primary element of what would become widely utilized home insulation, including attic insulation. By the 1940s, fiberglass products became the insulation of choice throughout the United States and much of the world.

The 1950s Through 1970s

An insulation product that was selectively utilized in the past came to the forefront beginning in the 1950s. This product was called cellulose insulation. Although an earlier type of insulation, it garnered only limited appeal because it was flammable, indeed highly flammable. This type of insulation is made from varying combinations of:

  • Newspaper
  • Cardboard
  • Sawdust
  • Straw
  • Cotton

By the 1950s, insulation manufacturers were able to add an effective fire retardant to cellulose insulation. By the 1970s, this type of insulation was in wide use in the United States and elsewhere around the globe.

The 1980s

What remains considered to be one of the most important advancements in attic insulation and insulation throughout a structure, is polyurethane spray. By the 1980s, polyurethane spray insulation was becoming widely used. As an aside, polyurethane spray was developed by the military in the 1940s.

Polyurethane spray insulation was considered preferable over fiberglass, asbestos, and other products. These other forms of insulation come in a blanket form that is not particularly malleable to fit into some areas. On the other hand, polyurethane insulation is sprayed as needed and readily fills in corners, divots, and other spaces that are hard (if not impossible) to reach with traditional types of products.

Attic Insulation Today

In this day and age, the most widely used types of insulation include:

  • Fiberglass
  • Cellulose
  • Polyurethane spray

When it comes to fiberglass attic insulation, in addition to the blanket or batt form that has been used for years, there now are loose-fill fiberglass products. This type of insulation does not come in a blanket or batt form. Rather, it is loose (as the name indicates) and is blown into a space to be insulated.

Other types of insulation being used today, but to a lesser extent, include:

  • Reflective
  • Foam board
  • Insulating concrete block

Threats to Attic Insulation

One of the greatest threats to attic insulation in a home, business, or other insulated structures are rodents. Mice, rats, and other rodents (including squirrels and raccoons) are known to infest attics. These critters will ruin certain types of insulation by gnawing it apart for use in building nests. In addition, when a rodent infestation occurs in an attic, the insulation will end up contaminated with rodent droppings and urine.

Rodent droppings can carry harmful pathogens, bacteria, and viruses capable of causing serious disease in humans. As a consequence, when a home or business has been infested by rodents, obtaining professional rodent dropping cleanup assistance is advisable. Through professional assistance, a home or business owner is in the best position to ensure that contaminated attic insulation is thoroughly and safely cleaned, sanitized, and returned to a safe condition.