Exterior masonry of any kind should not continue from outside into the enclosed inside portion of the house; there should be a break containing flashing and/or waterproofing. If such a barrier has been omitted, it will most likely have to be installed. Sealant or caulking is only a temporary repair at best. There is no way to know how to solve your specific problem without seeing a detail of the indoor/outdoor condition. If there is water in contact with solid masonry or a crack it will move through it by gravity, hydrostatic pressure, or capillary action (wicking) but in a properly constructed slab, a layer of coarse gravel or crushed stone (not fine materials like sand or clay) prevents water from being wicked up to the bottom of the slab (unless there is hydrostatic pressure present). Water vapor moves through a material if the air above the slab is drier. In a properly designed slab a sheet vapor retarder is sufficient to prevent water vapor from passing through the slab. In the case of hydrostatic pressure a waterproofing layer is required below the slab. None of this is difficult; it's standard concrete construction practice in commercial construction but it appears to be often ignored by home builders.

Well, its been almost 6 months since you posted about your Bamboo - how did it go and how is it holding up??? We installed 1000 feet of this exact product in Nov 2012 - we are currently in the process of pulling it all up,, YUCH... moisture issue???? not really sure what happened,,, installer is being real good and standing behind it all - the house is 1/2 up and the rest is coming out tomorrow.. going with eng Hickory in its place - also laying down a very expense moisture barrier (painted on) Only used Glue that was suppose to have a moisture barrier in it??? floor was 14 years old in Central CA - maybe 10" of rain a year and NO problems in the past... anyway,, moisture test is in progress at this moment - Wish you luck with your Bamboo - wife liked it but it does NOT like any moisture and does NOT like spoons dropped on it,, LOL - still a very pretty floor,,, oh well, live moves on

We had our whole house re floored in LVP In June 2021. Within a few months a portion of the kitchen started bubbling up and splitting at the seems. The flooring guy originally came and said that he believed it was sun damage coming from our glass sliding door. We ended up replacing the door with uv protection glass and the flooring guy replaced the whole kitchen floor with a moisture barrier paper underneath. During the demo they said there was possible moisture on the floor. We had a plumber out and he determined we did not have a leak. Just a few months later it started to happen again in a different area of the kitchen. When they installed the lvp originally they went right over tile, so this time he took up the tile as well so we could see what was happening. There was no obvious water or leak. We then had all our pipes looked at. Our drain pipes scooped. Inside and outside, pool, etc. Spent a ton of $ on tests. There was no leak to be found. We think we must have a foundation slab that has a high moisture content or the soil below has a lot of moisture? That’s all we could come up with. This time for the 3rd installation they put down a moisture barrier epoxy, a wood plank sub floor, and glued the lvp down to that. It made it a year after that, but we have the same problem happening again. So they have replaced the flooring in the kitchen 3 times in less than 3 years and it needs to be replaced again now. We had the manufacturer out and they of course blamed the installation. It is mind boggling. We have had so many plumbers, and flooring companies out and no one has ever agreed on what the problem is. So, I have to replace the kitchen floors again and this time need to do something other than the LVP that matches the rest of the house. I have heard about epoxy/ painted concrete flooring and thought that might flow better than tile. Do you have a knowledge as to if it would hold up to moisture fumes as that is our best guess as to the moisture problem we have? Tile is the other option and that is what was originally in the house and there didn’t seem to be any issues with tile. any ideas?

@Ryan Thanks for the question. A concrete slab that is sitting ON the earth (ie. not in a high rise on the 10th floor) always requires a vapour barrier underneath. Always. If anything, it maintains your warranty. There are three definitions of slab concrete: 1. Below grade. This is normally poured concrete for a foundation that has been dug into the ground. Like a basement. Even if 1 square inch is 'below grade' we view it as ALL below grade. 2. At grade. This is a common situation. Concrete is poured onto the ground and the house is built from there...going up; not down. Again, this is sitting 'on the ground' therefore it is considered 'damp' until proven otherwise. Even in the desert areas, we find dampness in slabs that are sitting on the ground. Moisture LOVES to condense on cold surfaces...like concrete. 3. Above grade or 'suspended slab'. This is the 'high rise' situation. You don't have to be in a high rise. It just means the slab is suspended in the air. It touches nothing but air above it and below it. This is the ONE situation where you can 'get away' without a vapour barrier. But you still void the warranty as soon as the contractor starts laying the first run. The installer is responsible for installing product on-site. If you did not purchase the vapour barrier, then the installer did not install it. If you used the SHOP'S installer, then they are responsible for ensuring you purchase everything you need for the job. Which requires you to tell them what your situation is. You get what you pay for. A good flooring installer *should have pointed out you needed a vapour barrier. And then would have told you what to purchase for him/her, or they would have said, "I have some in my truck, it will cost another $1/sf for the materials plus $0.50/sf to lay it." Something like that. And the preparation of the concrete is another thing that should have been paid for and performed. But so many contractors just want a paying job, that they offer the 'no frills' install. They get there, they install what is needed/purchased/sitting out for them and then they go home with a pay cheque in hand. I've had experiences where my QUESTIONS to the homeowner caused them to hang up on me. Yep. The question, "Is this for a bathroom?" caused such angst they started to yell it was none of my d@mn business and hung up on me. OKee DOKee then. I don't know what your situation is. The above is just an example as to why a store, with highly trained FLOORING professionals (ahem...a flooring store and not a 'big box' store like HD) would miss something as simple as a vapour barrier for a concrete slab.