Technically, the correct way is to caulk where the walls meet the shower floor. It's not really necessary, though, being that the shower floor is completely isolated from the floor structure by the pan membrane, and therefore, you shouldn't have any movement at that joint. You also might check once you can get in there to see if he just used the same caulking all the way throughout. I could see your concern if BOTH tubes were unopenned. But I can't see him caulking one place and not the other, if he knew that was what you wanted. He might not have realised there was a difference between the two tubes.

6-8 months, I'd say, before it looks like it starting to crack, then it slowly gets worse. It's a very gradual process, but we would like to fix it properly and are stumped. Initially (6 years ago, thought it was 8), there wasn't an issue. The shower space was great for a few years, but then the corner developed a leak/the caulk cracked. When the first leak started, we dug out the old stuff and re-did it with new caulk. My father in law could have glopped some clear silicone in there before re-caulking, we just don't know (he doesn't remember either!). I have used bleach to clean the shower, and while I think that's probably not the best thing to use on caulk, it can't be the reason the caulk job falls apart, can it? Do you have any advice as to how to tackle this issue? What steps would you take to re-do this area? We haven't used the shower for 2 months, so it's definitely dry. Thank you for any thoughts on this Bill V.!

If you remove the floor itself the sub floor should be checked for moisture content. It should dry out a little faster, and may have been protected by the floor above and any ceilings below. Make sure the testing is not just the surface, but the thickness of the wood. Deep pins or electronic RF meters are better for this. Short pins and surface contacts do not make the grade. Any decent wood moisture meter has a depth specification. Whomever participated in this should be fired. The GC should know better than to even consider installing wood floors in unsealed or uncontrolled (no HVAC operating) space, as should the flooring installer. All the water in the drywall mud has to go somewhere. Setting type mud is a little better than pre-mix, but still introduces plenty of moisture. Even latex paint adds a lot of moisture to the house. Framing lumber is not dried to anything like its final value inside a house. That is why shrinkage and cracks in walls can continue for over a year as the framing continues to dry out. My floor guy will not even think about laying strip hardwood until 2-3 weeks after the drywall is done, the first coat of primer applied. Even longer fr wider flooring, or any species he knows to be a PITA with warping. Many of the imported foreign woods are inadequately dried from the start. Neither he nor I make money on having to fix mistakes. The main products of burning is CO2 and H2O (water in vapor form). Kerosene heaters (AKA torpedo heaters) kick out a LOT of hot water vapor that gets into anything made of wood. Propane, natural gas, oil fired, etc. (anything with a flame) does about the same.

Bill, thanks for the info. For a moment, I was going for my dictionary and look up the word "acored". As a foreigner, I live close by several dictionaries... 1 in every room ;) So basically, is scoring like scraping out the grout? Does it needs to be all out or just enough to give room for the caulk to run into it for anchoring? I need to do this myself because if I ask my contractor to do it, he'd be insulted. I need to keep many years of good relationship with him. My home needs him! If you can direct me how to achieve scoring, I can get it done. I already got clear Silicone II for the job. Thanks again for all your teaching.