Dear Sandy:
If you apply a water-proofing membrane to your sub floor before installation, you should have any problem with leaving the holes of the stone open. They need to be filled in environments where you handle flood (kitchen) or where there's a lot of humidity involved (shower stall). Other than that, you can leave them open with no problem.
May I ask you now to please read and e-sign our Statement of Purpose at:
http://www.marblecleaning.org/purpose.htm?
Ciao and good luck,
Mauri
Article ID: 713
Created On: Mon, Oct 29, 2007 at 3:37 PM
Last Updated On: Mon, Oct 29, 2007 at 12:00 AM
Authored by: Maurizio Bertoli [mail@mbstone.com]
Online URL: https://marblecleaning.org/knowledgebase/article.php?id=713