The assurance of compatibility of sealants cannot be overemphasized. Every glass installation involves at least two sealants and frequently several more. These can be:

a) Sash joinery sealant
b) Exterior glazing sealant
c) Interior glazing sealant
d) Heel or toe bead
e) Insulating glass sealant
f) Butyral laminate in laminated glass

The proven compatibility of all materials involved is essential to the long term success of any glazing installation. Chemical reaction from physical contact of incompatible materials can occur. Less frequently, volatile constituents given off by one material can adversely affect another within the closed confines of the glazing rabbet. Sealant manufactures generally are willing to conduct compatibility test in their laboratories and to give the results in writing. Compatibility should always be investigated and never assumed.