Many clients and members of the industry have expressed concern about heating gypsum board, also called the plaster of Paris, a common building material.
What many people don’t realize is that these building materials are exposed to temperatures similar to a ThermaPureHeat treatment before they are used in construction. Often, materials are shipped through the deserts of Arizona and California, packed in trucks that are not temperature controlled. These temperatures may even exceed ThermaPure’s temperatures. Additionally, these temperatures are not monitored or distributed with the same expert care that ThermaPure technicians use.
Scientifically, gypsum board is used in buildings because of its unique and resilient properties. Gypsum board, like any other porous building material, will lose moisture through evaporation as the material is heated. Heating to 100°C (212°F) will increase conductivity of the material, increase thermal expansion of the material, but the mass loss of the material is virtually unchanged. As the gypsum board heats the energy is used in the gypsum to begin dehydration. All of these minor physical events occur as the material begins to dehydrate. This takes place up to the beginning of calcination at 100°C. It does not appear that any damage is done when this activity takes place over a fairly rapid period of time, as is done in a ThermaPure process. The significant changes to the material occur after calcination begins and most occur between 100°C and 200°C.
There are few studies that show what happens to a gypsum material that is heated up to 100°C (212°F) and then returned to ambient temps. The sense is that the restoration to ambient temperatures will return the material to a normal state because no chemical change has taken place. Calcination is a process that occurs in gypsum board in which the level of both liquid and vapor moisture are dehydrated. It appears this process begins at 80°C (176°F). There are several citations in which the researchers talk about temperatures of 100°C (212°F) as the approximate temp that calcination begins. Either of these temperatures are typically in excess of a ThermaPure process. One of the research papers (Fuller) states that comprehensive strength of gypsum board actually increases up to 100°C.
With years of experience, and thousands of jobs completed successfully, ThermaPure is familiar with the complexity of heating structures. We have taken a simple concept, pasteurizing buildings, and applied it to modern homes and commercial buildings. Each job is analyzed individually for the best results.