# Caulk, Silicone and Sealant � Are they the same or different?



## Daniel Holzman (Mar 10, 2009)

Silicone is a term used for a variety of products with the following chemistry:

_A durable synthetic resin with a structure based on chains of alternate silicon and oxygen atoms, with organic groups attached to the silicon atoms._

Sealant is a term based on the verb to seal, meaning a product designed to keep out a fluid, usually water.

Caulk as a noun mean _A waterproof filler and sealant, used in building work and repairs. _Caulk as a very refers to the installation of caulk.

So caulk and sealant appear to be essentially identical, whereas silicone is a type of sealant or caulk.

How to select the right material. Read the labels very carefully, there are thousands of sealants and caulks out there, they typically are designed for different applications, they have different warranties, different lifespan, different costs, and different application techniques. Only the manufacturer can tell you what type of application they will work on, and sometimes the manufacturers do not tell you the whole story.


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## stadry (Jun 20, 2009)

never thought about that but it is confusing, isn't it,,, generally speaking, most sealants are installed over a bondbreaker meaning they only adhere on either side of something ( pavement joint, building stress relief jnts ),,, caulks adhere on all surfaces but do not weather the expansion/contraction stress as well.


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## Gary in WA (Mar 11, 2009)

Don't use a caulk when you really need a flashing or backer rod and caulk; http://www.fpl.fs.fed.us/documnts/fplgtr/fpl_gtr169.pdf


Gary


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## Maintenance 6 (Feb 26, 2008)

Sealant and Caulk are interchangable terms for the most part. As stated, silicone happens to be the base material for one type of caulk/sealant, as are urethanes, latex rubber, butyl, poly-sulphides and a few other compounds. It is important to select the right caulk for the material being sealed and to create a joint that works with the properties of the material and the caulk. Here is a link that will show some typical joints.

http://www.masterwall.com/files/mw149-020104sealantdesign.pdf


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