- Bob - wrote:
In a typical tiled shower installation, is the grout waterproof so
that it keeps water out of the lower layers?

Almost all grouts (some epoxy grouts are an exception) are somewhat
permeable to water, in any case there are will likely be mechanical
imperfections in the grout, increasing over time, which will admit
water by capillary action

Generally tiled bath and tub walls are installed to a rigid backing
material highly resistant to water damage ("Durock" is a common
example) with a vapor barrier behind that, if a tub or shower floor is
tiled it's generally installed over a (hopefully) watertight assembly
called a "pan", which usually incorporates a waterproof
"liner".

See for example:

http://www.tileshop.com/diy/showerbase.pdf

Michael Thomas
Paragon Home Inspection, LLC
Chicago IL
mdtATparagoninspectsDOTcom

- Bob - wrote:
Are there any products that could be used to waterproof or water
resist older grout ?

A sealer, Bob.

--

dadiOH
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