Be sure you understand the options. There are 2 kinds of crawlspaces allowed by the IRC: Vented and Unvented (aka "sealed"). The terms "unvented" and "sealed" are misleading because this type of crawlspace is not completely sealed or unventilated. The IRC code requires that both of these types of crawlspaces be "ventilated" so that moisture does not collect and encourage the growth of fungus (whether from the ground, condensation on the slab, etc.) by one of the following methods: 1) "Vented" Crawlspace - install vent openings in the exterior wall of the crawlspace 2) "Unvented" Crawlspace - inside the house supply to or exhaust from the crawlspace a small amount of air with a return air path to or from the house and insulate the exterior walls of the crawlspace. Both crawlspaces must have a vapor retarder at ground level and an access opening. For more information see IRC section R408.1, 2, & 3.

The head of the bathtub/shower is what is next to the toilet, and it's 7 foot wall. Water would have to take a large turn around the corner to get by the toilet, so that would have to some impressive shower splashing to get there! Our concern was more that maybe a pipe had broken underneath in the concrete slab -- is that possible, and if so, would it cause the dampness that we're seeing? I do think the more likely explanation is the toilet, though, considering the pattern of the water in the linoleum (looks like it spread out from the base of the toilet). We've owned this house for 3 years -- the dark marks in the floor were there when we bought it, so obviously the toilet was leaking before we bought it. We actually had a new wax ring installed a year and a half ago, by a professional plumber, and yet in that time, there appears to still have been dampness issues. I would hope a plumber would be able to install a wax ring correctly! Does that suggest to you a problem with the toilet itself? We were thinking of doing the following: 1) Having a plumber come in and look at the toilet flange and make sure it looks good, and if not, have him replace it. It actually looks kind of old and questionable to us, so it may be part of the problem. 2) We'll go ahead and install our new tile floor. 3) Buy a new toilet, just in case the problem was actually with the toilet itself (it was here when we bought the house; have no idea how old it is). 4) Have the plumber back out and install it, since I don't want to take any chances with this. Thoughts?

I had the exact same problem. I picked out the vanity I wanted but did not think about the fact that it wasn't made to sit flush against the wall. I spent a month looking for something else, but in the end we decided to go with something shorter and have it not be against the wall. But we were going from 72" to 60" which is probably not workable in your mom's situation. I did find a lot of vanities that did have flat sides and could work in a corner, if you are willing to have the countertop fabricated. They just need to not have any trim detail on the top or bottom like the one you picked out does. I would just look at the ones without the pre-made tops. Because the pre-made top will still leave you with a slight gap because of the countertop overhang. This is an example: Avanity Modero which is sold everywhere, not just at Lowe's. The cabinet we ended up buying is an Avanity Madison which won't work for you, but I assume it is of similar quality. We are pretty happy with it. The drawers and doors have soft close but I do feel like the glides in my Ikea kitchen drawers are better quality. It is very pretty and I wanted a stained wood so I am really happy with our choice. If I had been willing to go with a painted finish, I think we might have stuck with the 72" Modero.

You mean waterproofing PRIOR to installation of tile as well as during/after install? Yes, you have to build and waterproof the shower before a single tile is installed. Tile and grout are not waterproof, they are just the part that you see. Not a pro here, but to educate myself (after a shower disaster, and in order to make a better hiring decision when searching for new pro to fix bathroom), I read the shower chapters of the TCNA handbook, read waterproofing threads on this forum and the John Bridge forum, and checked out DIY books from the library. I wasn't intending to DIY, but it was very helpful to learn what building a waterproof shower really requires. There's a lot of bad info out there, so don't go digging around in YouTube videos, with one exception - I watched Sal DiBlasi's videos. I think he has another site with more info on it, but I haven't gone on there lately. Doing some research before talking to contractors will help you make a better hiring decision. You can order a downloadable version of the handbook for less than $40: https://www.tcnatile.com/products-and-services/publications/218-english-publications/188-handbook.html You can search for Sal's videos online: Sal DiBlasi, Elite-tile Company, in the Boston North Shore area. After you educate yourself, start interviewing contractors (not sure if you want a GC or if you are going to directly interview tile professionals). Ask this question: "How do you build a shower?" For your entertainment here is a story that illustates how hard it can be to find an excellent tile pro, and how vulnerable people are to GCs' hiring decisions regarding subs. When you do find an experienced and qualified tile pro, understand that on average a correctly built and waterproofed shower will be several thousands of dollars. Don't skimp on this by hiring an unqualified person. The chances of a leaky shower is far too great a risk. https://www.gardenweb.com/discussions/5725013/what-to-do-when-a-project-goes-completely-south#n=28 In my case, I hired a very expensive GC, who then hired a very cheap and unqualified tile installer. If you hire a GC, you need to find a way to ensure that he/she doesn't cheap out on the tile pro to increase their profit. I haven't found a way to do that yet. The only 2 projects where I had to hire a GC, they did this and it caused big problems. So, if you hire a GC, have an honest talk with them about who they are going to hire to build your shower. The tile pro is the most important sub that will be involved in your bathroom reno. The tile pro is the one who is in charge of building the whole shower. Sometimes a framer will frame the shower, but the tile po is ultimately responsible for the whole thing. Don't let a GC just tell you the person is qualified; you need to see that tile pro's prior work and ask them the question "How do you build a shower?" and here his answer for yourself.