here where we dont get earthquakes :) the standard is to use a sealant along the bottom row of tiles but if you asked two contractors in your area and they both do it the way you describe, I would say there is a reason for it. What it sound like to me is that they grout because it looks better but there is still a layer of sealant over the top in case the grout cracks etc to protect the joint or they are using sealant first and the grout goes over the top to cover the sealant? Sealant doesnt last forever anyway and if it comes off then it would just be a 5 minute job to redo it so I dont think it would be a big deal as long as there is some sealant there for protection. Just my thoughts :)

Thanks to all for your feedback.This is a fantastic product. I originally found it at PPG Paint Stores. My family sent it to me and it arrived perfectly. We have my husband's train room above the living room and I wanted a completely finished ceiling over the exposed rafters. He didn't feel we could use cement board,and we don't use dry wall here. Because of the wood floor above which is movable he felt anything that wasn't flexible would crack. I coverered the rafters with twelve sheets of 4 x 8 luan and used the krackote on every seam. The ceiling looks perfect and a year later no hint of any cracks. I use the tough kote on the exterior areas of concrete that are a little rough and the krackkote inside. I think it is a wonderful product. You can order it directly from tkocoatings in Illinois and they will send it UPS to your door. The web site is tkocoatings.com and phone 815-338-2006.If I could ever fiqure out how to post pictures I would include them but it is hopeless. If you email me I can send them as an attachment to the email. Good Luck AJ

I find myself doing this on a regular basis, now that I'm retired and don't have a schedule.

Christopher Nelson, I did go to that page before but this time I realized you could ask questions there at the bottom of the page. They gave me a response pretty quickly, which I appreciated, and I will share it here in case others are wondering about this: At a companion article RESILIENT SHEET FLOORING ID GUIDEinspectapedia.com/hazmat/Sheet_Flooring_Identification.php we start our article series about asbestos in sheet flooring productrs. At ASBESTOS DUCTS, HVAC -inspectapedia.com/hazmat/Duct_Asbestos.php we discuss the use of paper both as a joint tape and as a total; covering on heating air ducts in older homes. Don't panic - but do avoid creating a dusty mess. Or if you have to face a dusty demolition then I'd have the material tested for asbestos Search InspectApedia for ASBESTOS TEST LABS if you need that service. Trivial cuts (an installation drill hole) ought never justify expensive asbestos testing and remediation, but even there you could minimize risk by either wetting or more-likely by using a HEPA-rated vacuum for dust control followed by damp wiping cleanup. ******************** klem1, thank you for your response as well. I would like to get it tested but at the same time, even if it tested positive (which I wouldn't be surprised by) it seemed unclear as to whether a small nail hole or drilling holes was okay. The inspecapedia response helped, and I did find another suggestion online that said (if drilling) to fill a small paper dixie cup with shaving cream, put the drill bit through that onto the hole, and then lower the cup and hold it flush to the surface as you drill.