[GBlist] Sealants

[FUnger@aol.com]

On the original post, Silicone is a structural seal and polysulfide or 
another material is the primary moisture seal for insulated glass with dual 
seal. Must be some reason manufacturers offer much longer warranties on 
these. (perhaps because it works)

As for silicone outdoors: Dow, Pecora, GE, Tremco and other manufacturers 
typically offer 20 year warranties on their commercial silicone sealants vs 5 
year warranties on urethanes and no warranty that is meaningful on all the 
acrylic painter caulks and other junk in hardware stores with the bold 
warranty claims. On sealing skyscrapers with multi-million dollar sealant 
contracts and even higher liabilities for failure, silicones are typically 
the preferred sealants with most substrates. The stuff you get at the 
hardware store is typically not very good but is safer to handle. A good 
commercial building sealant or glazing material supplier can direct you to 
good silicones that will outlast almost anything else.

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