As is indicated by the “bluish” highlighted areas in the picture, these are areas of enamel steel type tubs that the moisture meter often finds indications of moisture behind the wall covering. On a recent new construction inspection I found a great example that shows why this is so. Steel tubs like this typically have a flange that runs up behind the wall covering to reduce the chance of water finding its way into the wall. The problem with this flange is that it does not run all the way to the edge of the tub or down the side. In this next picture one can see the flange where it stops at the black opening that is a hole all the way through. Really this opening should be properly caulked and sealed previous to installation of the finish surface to reduce the risk of water penetrating this area. Then of course the gap should be properly caulked after the finish wall surface is installed. The way these tubs are constructed speaks to the importance of keeping grout and caulk in good condition. Similar indications of moisture are also very common at the inside corners of the tub because this flange does not wrap around the corner but instead ends just before the corner----just like in the picture at the front of the tub. This creates an ideal place for moisture to find its way into the wall at the corners due to improper caulking of the corner prior to installation of the wall surface and poor caulking at the wall surface connection with the tub. Doesn’t it make you wonder why they would build the tub this way? Apparently it has to do with the way these steel tubs are manufactured and enameled that make it very difficult to do a proper flange all the way around the tub like a plastic tub would have----and part of what makes this type of tub a “cheap” choice in tubs. I think now you can see why inspectors are so adamant about keeping these areas well sealed/caulked.
Charles Buell
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WA State, Home Inspector Advisory Licensing Board
Boy, I've seen enough of these cheap steel tubs! After they have been in place for about ten years you can see the trade off of price versus value. Cast Iron still rules in my book.
Michael, I wish that was the case here----about 50 percent of all new construction has at least one tub that is enamel steel.
Charles, so many times the plumber (while setting the tub) forgets where he put his level. The tub should be very level (not sur ehow you can be more level than level), it is design to drain water back into the tub. Installers many times don't pay enough attention to this fact. The green board underneath the tile should go almost to the surface and then be sealed between the enamel and the green board. Since the board overlaps the tub flange during installation it is pretty easy to make it water tight if it is done correctly.
Jack, greenboard should never be used behind tile and it is not a recognized substrate for tile by industry standards.
Ahhh...water. It just finds it's way into the darndest places.
Jim---it do indeed.
I see you're using those neat little color examples again. I still want to learn it but haven't. Nice looking blog.
Thanks Barbara
And I believe that to be a peep hole - great for fly catching.
Very kindly,
Croakster
Charles you obviously haven't seen some the newer homes around here. I would prefer to see hardi-backer, but what you see is sometimes what you get.
Croakster---great idea---frog hide as a shower enclosure. Perhaps you can answer a question that has "bugged" me for years----do frogs sweat?
Jack, again it is that dang "minimum standards" thing again:)
I love to stop by here. I always learn something useful. Thanks!
Well, it is always great to have you stop by here as well:)
Very kindly,
Croakster
Croakster---I think it would be a deafening sound to step on you in the shower.
Charles, you said it all! I've seen too many of these also. Great blog, now featured at http://activerain.com/groups/virtualoffice
Thanks Regina
Hard to believe that large gap would have been left on a new tub, but then again not really.
James, I think that they just never got around to doing the final caulking. What bothers me is the poor prep of the surface behind the tile. I am sure you see the bluish colored areas with your IR all the time:)
Charlie,
That is a great shot of the gap. Sure explains the problem at corners. I often find problems at the wall at the lower runner on the sliding glass shower doors too.
It is pretty unusual to get such a great view of this problem
Mr Charles,
When I bath I do so in the wide open ocean. I find it very refreshing but I am armed against squid.
Your friend Nutsy W
Hey Nutsy---want to meet my pet pyranha?
Hey Charles,
Great pic, I use to have problems with water enetering these areas in my apartments ...... a real pain in the but...and in the ceiling to the unit below.
Sean Allen
Sean---over and over and over and over.......
Dear sir,
I have recently had 2 Briggs steel tubs (enameled) installed into a new home. After using the tubs a few times i noticed what appeared to be pin holes in the enamel. I had a couple of guys (one is in the cultured marble tub world and the other was in the tub repair business) look at the problem. They both said that the tubs were defective, that it appeared that the enamel had bubbles in it and the popped once the tub was put into use. I am not in discussion with the maniufacturer to make me whole, but they continue to make me jump through hoops to get them to replace or repair.
Is there a way i can find out how common this issue is with Briggs tubs. I would love to have some data showing that i am not an isolated issue, to assist in getting the resolve that i need.
Thanks for your assistance,
Jerre
Jerre, that is an issue I am not familiar with but that brand of tub is not common in this area. Have you tried Googling the issue? It is hard to imagine, from what you describe, it not being some sort of factory defect.
So it sounds like these tubs are okay if you are careful to seal all gaps - before and after tiling. Replacing a flimsy acrylic tub ( big mistake ) with one of these for $69.00. I can affort extra materials to waterproof those areas! Thanks for the great info!