Although spray foam insulation as we know it today truly emerged in the 1980s, spray foam actually has its roots several decades further in the past, beginning with the development of polyurethane foam in the 1940s by Otto Bayer.

Otto Bayer, an industrial chemist, actually began working with polyurethane in Germany during the late 1930s. This technology was brought to the United States in the early 1940s by David Eynon, the president of Mobay, a war effort conglomerate created from the partnering of two chemical industry giants, Monsanto and the Bayer Corporation. Although Otto Bayer worked for Bayer Corporation, he was not related to the company's founding family.

During the 1940s, polyurethane polymers were used primarily in military and aviation applications. The production of war machines for the World War II conflict drove most of the applications of these high-grade plastic polymers for the duration of the war.

It was not until the 1950s that polyurethane began to be used in home insulation. It was the invention of the "Blendometer" that allowed for expansion of polyurethane application to the home insulation realm. The Blendometer was the first machine able to mix components for the creation of polyurethane foam and was created by Walter Baughman in 1953.

The Blendometer allowed for the strategic mixing of chemicals to create what Baughman called a plastic elastomer or an expanding foam. Liquid when applied, this plastic elastomer expanded into a thick foam and eventually hardened upon drying.

Baughman's Blendometer was still a partially manual process, with humans tilting trays of chemicals to mix foam. While the machine did allow for the use of polyurethane in home insulation as well as in other home-related applications, like air conditioner insulation, it was still a technology in its infancy and one that made widespread use of polyurethane as a residential insulation material no less cumbersome.

Polyurethane polymers were used in a variety of means throughout the following decades, with incredible advancements being made in the auto industry applications of the material in particular. However, it would be more than two decades before the foam would become widely used in home insulation processes.

Building on Baughman's invention, the first dedicated spray technology machine was constructed in 1963 by Fred Gusmer. The 1960s and 1970s saw technological advancements which made spray foam's use in home insulation more easily achievable and affordable.

It was also in the 1970s that the idea of the "super insulated" home emerged. Largely driven by the energy crisis of the 1970s, home builders and homeowners alike began to look for ways to improve the energy efficiency of homes.

The crisis fueled advancements in technology that laid the foundation for modern spray foam applications. It was the development of advanced spray nozzle technology that allowed spray foam insulation to be used widely in home construction and improvement projects.

The spray foam nozzle allows the foam mixture and the chemical responsible for its expansion capabilities to be separated until just prior to application. The spray foam mixture consists of several key components but it is the expansion chemical, isosynate, which is responsible for its easy application and expansive character.

The application nozzle allows the foam mixture and the isosynate to be delivered to the nozzle through separate hoses, mixing only seconds before being sprayed. The spray foam arrives at its destination as a liquid but quickly expands into a foam substance and later dries into a hardened plastic upon curing.

The 1980s and early 1990s saw a great deal of controversy within the spray foam insulation industry as different marketing schemes from various companies promoted the benefits of closed verses open foam insulation and as some companies tried to market water blown foam application processes.

Though there has been much debate within the industry, R-value standards, used as a measure of determining energy efficiency, have cleared up much of the controversy. R-value ratings clearly define closed foam as the most effective means of making a home as energy efficient as possible.

Closed cell spray foam has additionally been added to the list of building requirements for making homes in hurricane and earthquake zones more structurally sound. The improved stability of homes insulated with spray foam technology makes the use of spray foam a smart move for any homeowner regardless of geographic location.