Expert Answers
What could cause water to come up through my Grout Joints?
QUESTION
For the last couple of months I have been dealing with water droplets coming up through grout in my dining room area and leaving a white powder (efflorescence ) located at the front of the house in Florida.I have had everybody possible out to help remedy this issue. There is no plumbing under the house anymore since I bought the house 6 years ago (we ran all new plumbing lines through the attic). The drain lines under the house have all been checked by several companies (cameras) and they are not leaking nor are any sprinkler lines leaking.
I had a drain joint fixed in the front of the house that was not installed correctly but it was not leaking so this was not the problem.
Since they had to dig to fix the joint I did see that water was sitting in the front of my house (in the hole) for probably longer than it should 2 days after rain or sprinklers. I had a engineer come out and basically they said it is from ground water coming up through the slab. This past weekend I had french drains installed around the front of the house.
My main question is how long would it take for the water to stop coming up through the grout after the french drains were installed (Its still coming up 4 days later). The dining room are all marble floors when we were trying to figure out the issue we did pull a tile to see if we could see anything. It was wet underneath. I am pulling some more tiles Thursday because I happened to have a old picture of the floors right before they put down the marble and saw a spot close to the problem area where it appeared the slab may have had a crack patched. If the French drains do not work what should I do? I would hate to rip up the marble floors (It would be very expensive) and if I did then what? We are also trying to sell the house (not because of this issue) but have removed it from the market until we remedy the issue so something needs to be done as soon as possible. Any advice would be very much appreciated.
ANSWER
ANSWER - Your engineer was basically saying that you have a high water table, meaning that the underground water is very close to the surface of the ground.The french drains only work if the source of the water is away from the french drains, and that there is a slope to the french drains so the water travels towards the french drains and then evacuates away from the house. If you have a high water table the french drain won't keep the water away from the bottom of your concrete slab.
So the water from the high water table must be in contact with the concrete slab so the water migrates into the concrete slab and up through the grout joint. When it rains the water table rises so you would tend to get more water coming through the grout joints.
As the water passes through the ground, the concrete slab, and the tile setting materials it picks up minerals, which is a form of salt. The minerals dissolve into the water and when the water reaches the top of the tile it evaporates and precipitates the minerals leaving a whitish residue and it can cause spalling (surface deterioration) in the marble surface.
Houses should have a vapor retarder under their concrete slabs that continues up the sides of the slab so water cannot migrate into the concrete slab and up into the home. Either you don't have a vapor retarder or it was installed in correctly.
You could remove the grout and install an impervious epoxy grout or an ASTM C920 sealant in the grout joints to make it water tight, but the water migration can still cause problems to the marble. The only way to properly solve the problem is to replace the marble. When you do clean and scarify the concrete slab and waterproof it with one of the epoxy based systems that uses a cementitious self-leveling underlayment so you can then adhere the tile to the underlayment.
12 thoughts on “What could cause water to come up through my Grout Joints?”
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I, too, am having this same problem. You suggest removing the tile, “sealing” the slab, and replacing with an epoxy grout. Can you give any suggestions as to what to do to prevent the water from coming in at all? Can a vapor retarder be installed on existing home?
The traditional vapor barrier that is a sheet membrane that goes under the concrete slab can’t be added after the fact.
You can apply an epoxy vapor barrier over the surface of the concrete slab to prevent moisture from coming through the slab.
In theory, if you know where the moisture is coming from, you can install French drains in the ground to divert the water from reaching the concrete slab.
I have a tile floor in dining room that has one very small area (-1/2” sq) in a grout line that gets a droplet of clear liquid. I clean and dry area and the droplet reappears over a few days. This is a 5+ year old porcelain tile floor. What in the world is this?
When water migrates up through the grout joint the tough question is where is it originating? You could have a high water table and when it rains or a nearby river swells up the water table rises. Could be water is migrating from the outside of the house in a planter or further away where it is the source of the water.
You could have a pipe the concrete slab that is leaking slowly. It could be that surface or underground water is draining towards that house during these heavy rains. Either way the assumed concrete slab is being subjected to water from one of these conditions.
Either your concrete slab does not have a vapor retarder to protect it from these water intrusion conditions or the vapor retarder wasn’t installed correctly or the vapor retarder used is so old that it has degraded and is allowing water to reach the concrete slab.
The solutions are like the suggestions in the above answers to the other questions. You need to determine the source of the water. There is a chance if you dig a french trench drain around the perimeter of the house you will see evidence of where the water is coming from. There is a chance that installing a trench drain might divert the water to the storm drains if done properly. It might be necessary to remove the tile floor and repair the crack and install an epoxy moisture migration system to then bond the tile to it.
I would first file a claim with your insurance company. They can recommend a water damage restoration company who might be equipped to remediate this for you. Maybe or maybe not it will be covered by the insurance company.
House flooring same level as groung level outside. Ground water level up in rainy season, as seen in adjacent well.
Have installed a pump to lower well water level, expecting it should reduce water pressure below flooring.
The pump in the well probably won’t make a difference as there is likely an abundance of water within the water table.
You will probably have to install French trench drains around the perimeter of the house to redirect the water to a drainage area.
I have four areas where water has been coming up forever in the grout. It’s not a big deal, but I do know it feels hollow under each of these tiles. I believe there are cracks in my foundation, but nobody has mentioned that. I also live on a corner of a canal leading out to the Gulf, thus a high water tsble, but only in four spots, about 5-6 ft apart.
Chances are the four areas where water is coming up is due to the high water table. During storms the water table will rise and that can cause hydrostatic water pressure causing the tile to debond causing the hollow sound.
The spots where the water comes up are paths of least resistance for the water to travel, for one reason or another, and it likely relieves the underlying pressure so it doesn’t come up in other spots. The only way to mitigate that is to divert the water by installing a trench (French) drains on the outside perimeter of the house to divert the water to another direction from the house.
What type of professional would investigate this slab floor tile grout getting wet? tx
It may not be easy to find a professional who will perform this work or who will at an affordable amount. Or who has the overall understanding how to evaluate this type of problem and who can prescribe a repair.
There are plumbing leak experts who you can hire to see if they can detect a leak in the plumbing, but if the source of the leak isn’t from the plumbing they might not be able or willing to look further than that.
Geotechnical Engineers are experts at evaluating the soil and can determine if there is a high water table or if there is a source of water reaching the house from outside through the soil.
A landscape contractor can did trenches around the house and can install French trench drains with perforated drainage pipes with socks over them connected to an outside drain.
Tile experts like CTaSC can come in and evaluate the tile floor and look for evidence of where moisture is coming up. Then we would remove some tiles and take a core sample down to the bottom of the slab and look for evidence of a vapor retarder or gravel and see if there is any evidence of water coming up. The core profile would tell us whether the water is migrating up from the bottom or if the water is coming into the slab laterally. Based upon those findings we would either prescribe a repair or determine if we need to do more evaluation to identify the problem.
Keep in mind that the water coming through the grout is a symptom of a problem. You can’t treat the symptom of the problem expecting that will fix the problem. You have to identify the problem in order to determine how to remediate the problem.
Hi, we are in a situation that seems fairly common on this forum. Two years ago we purchased a house in South Florida and replaced the existing tile. The installer said one room’s slab was particularly moist and applied AquaDefense there before laying our large format tile. No cracks were seen. The home had poor drainage near the room so we regraded and added gutters and assumed the issue was mitigated. The room has had persistent efflorescence and puddling in the middle of the room’s narrow grout lines. There are other areas of minor efflorescence throughout the home and the grout is not a uniform color. We have ruled out a plumbing leak and believe we are dealing with hydrostatic pressure from below the slab and assume the barrier was non existent or compromised since the home is 40 years old. When I removed grout from one of the areas of efflorescence there was actually a noticeable pressure release sound, like opening a soda can, as water seeped out and when we tried to cover the area with moisture wicking pads and a rug, a new spot popped up beyond the rug as if the floor was still trying to breathe.
We have consulted with a plumber, foundation company, structural engineer, tile company, drainage company, and probably others I can’t recall. We have not been given a consistent course of action. Do you believe French drains would help minimize the pressure in this area of the home? Is there anything special we would need to do with the drains if the focus is moisture below the home and not surface water? Is there anything else we can do to draw out this moisture without ripping up our new tile, or should we pursue tile removal and application of an epoxy moisture barrier before laying new tile? I assume if we only remove and replace the one room, the moisture could migrate? Thank you for your help.
Based on your description, it does indicate that you have a hydrostatic moisture problem. It could be from a high water table that rises during wet events and subsides during dry times. Apparently you do not have vapor retarder under the assumed concrete foundation to prevent the water from migrating up through the concrete slab and tile assembly.
To mitigate the problem you need to divert the water to a drain away from the home. Depending on the underlying conditions, by placing a subterrain drain (french drain) adjacent to each side of the house deep enough with enough capacity to divert the water away from the house that could solve the problem.
Although if it is a water table condition that might not be enough to divert the water away. It is possible to dig large sumps and use a sump pump to pump the water away.
You should consider hiring a geotechnical engineer who specializes in studying soil and ground water and he could do testing to determine the underlying conditions.
If you needed to replace the tile floor, there are epoxy moisture mitigation systems that prevent moisture vapor from passing through. Although it will not prevent hydrostatic conditions from causing it and the tile assembly to lift up under certain hydrostatic pressure conditions.