The Blog

Surprising Insulation: What It’s Actually Made Of

By Chuck Henrichsen on June 11, 2014

Insulation is an important part of a home’s construction. Without proper insulation, the structure can become incredibly cold or excessively hot. Moisture infiltrates, mold grows, wood rots, and the house’s structural quality begins to fail. How does attic and crawl space insulation actually keep all of these inconvenient problems from occurring? What is it made of and how does it work? Insulation can take on many different forms and be made of many different substances.

Fiberglass Insulation

Fiberglass insulation is made of a mixture of natural sand and recycled glass. It's heated to 1,450 degrees celsius, and then converted into fibres using a process similar to making cotton candy. The fibers are then held together by a binder that 'cements' the fibers together. These binders are made from plant-based products consisting of a carbohydrate (maltodextrin) and a vegetable oil. These are sometimes called 'sugar binders'.

Cellulose: Natural Plant-Cell Insulation

The word “cellulose” comes from the root words “cellule” and “glucose.” A cellule is a small living cell and glucose is sugar. Cellulose is formed of the cell walls plant cells known as polysaccharides (carbohydrates), which are formed from a large number of sugar molecules bonded together. This natural type of insulation material can be made from cells from trees or plants, or it can be made from human-synthesized products such as newspaper. Most cellulose insulation is made from newspaper, but it can also be produced from straw, sawdust, cotton, corncobs, or hemp. Because the resulting insulation material is usually highly flammable, the substance is coated with a fire retardant substance.

Cotton: The “Blue Jean” Insulation

This type of insulation has risen in popularity due to it’s environmentally friendly characteristics. It’s generally made from recycled blue jeans, though any recycled industrial cotton scrap will do, resulting in little to no further damage to the ecosystem. The manufacturing process is much simpler than the intensive production methods for other forms insulation, such as fiberglass. Boric acid is generally used as a flame retardant and the substance is bound together with an adhesive made from melted polyolefin (a type of polymer).

Spray Foam Insulation: An Expanding Composite Material

The most effective type of insulation, spray foam insulation is made from a composite material known as polyurethane. One of the components used to make this substance is isocyanate, an organic compound made from tweaking the molecular structure of isomeric cyanic acid. Isocyanate is combined with polyol resin to make polyurethane. When sprayed out of the tip of the spray foam gun, the substance expands. There are two types of spray foam, closed cell and open cell. As their names indicate, the cells of ‘open cell’ insulation are left slightly open, as opposed to the more densely structured closed cell spray foam. Here in the soggy northwest, we favor closed-cell to keep moisture from building up in your insulation.

Understanding the general makeup of these various types of insulation is not only interesting but it also educates us when faced with a decision regarding what type of insulation to choose for a given task.

For more information regarding insulation installation and crawl space care, contact Clean Crawls and request a free quote.

Chuck Henrichsen
President and CEO of Clean Crawls, Treasurer of E3 World Wide, proud husband and father.