The goal of this test is to measure how well a cured sealant product can withstand building movement. During this test, the sealant product is sandwiched between two pieces of a substrate using a precise mold. Once the sealant has cured under controlled conditions, the testing sample is placed in a machine that subjects it to cyclical extension and compression forces. The test is designed to see if the sealant can handle joint movement of +/- 25 percent. At the end of the test, the sealant is required to maintain its adhesion to the substrates while staying cohesively intact. If the sealant passes these checks after being exposed to the +/- 25 percent joint movement, it has achieved the ASTM standard.

OSI QUAD MAX exceeds the ATSM benchmark by being able to withstand double the joint movement applied in standardized testing. With a joint movement capacity of +/- 50 percent, QUAD MAX is one of the most flexible sealants on the market. A flexible sealant is better at distributing stress caused by the substrate expanding a contracting during weather changes.

A sealant with a lower tolerance for joint movement could start to crack, peel, and lose adhesion. Any failure increases the risk of the building envelope becoming compromised – resulting in water penetration and damage. On door, window, and siding installations, using a sealant that can accommodate high cyclical joint movement long-term, might require a class 50 sealant.   

This ASTM test evaluates the effect heat exposure has on a sealant product that has fully cured. Using a brass mold, sealant is applied congruently onto three different aluminum panes and are set to cure completely under controlled conditions. The samples are weighed and are then placed in a specialized oven at a temperature of around 158 degrees Fahrenheit for 21 days. After that time, the sealant samples are weighed again to determine the loss percentage due to heat exposure.  The beads are also examined for cracks and measured on a scale of 0-4 against a control specimen (CGI control samples below). Zero represents the absence of any cracks in the cured sealant product.

This standard is one of the best ways to see how a construction sealant will perform long-term in high-heat conditions. It is a predictor of success but not necessarily a guarantee of durability.

OSI QUAD MAX exceeds the ASTM C920 standards outlined above. It gives pros confidence on the job site with reliable performance against the elements. Learn more about the benefits QUAD MAX brings to door, window, and siding installation projects today.

^{Disclaimer: the information provided is intended to offer a general understanding.  OSI recommends you seek out technical data sheets, speak further with an expert and/or gather additional performance information before making any final product decisions.}