There's No Moisture Barrier Under My Home

Welcome to CR4 Mary Ann. There are heaps of people here who will jump at the opportunity to help you with this and from the start you have our utmost sympathy. You have "inherited" a nightmare with no easy fix.

The suggestion to cut out the floors, install a moisture barrier and then re-pour the floors should work, provided that while they are doing this they also pay attention to the areas underneath the walls. This DOES require professional involvement since the structure will need to be protected from subsidence while this is happening AND the new floor will need to be "tied" into the remnants of the original slab under the walls. [Probably by drilling and inserting rods that will cross the join into the new floor slabs.]

There may be a solution in using an injectable "grout" into the subfloor material. There has been a lot of research into prevention of "rising damp" and your place may be a candidate for similar treatment. This would only involve drilling a matrix of holes through the floor and injecting the material through those. Given the choice, if there is an available solution of this type, then that would be my preference, rather than have a butchered slab for the floor.

Hope all ends well.

Thanks so much for all the feedback. I guess I left out a few bits of vital info.

First, I live in Florida (central), thus no basement. I have put up gutters on the one side of my house that I know there is a problem. We dug a french drain from the back of the house down to the front tied the gutter down spouts in the the drain, The pipe we used is slotted, so that the ground water also will seep into the drain and out to the front and onto the street. We also, lowered the ground level in several arear around the souse and installed rock in lieu of mulch to help drain water awar from the house,

Second, the house was build in 1988 on monoliftic(?) slab. The builder has since left Florida and commited suscide! Since all this has started, I have been told that the builder, Malin Homes, was told that these "California homes" should not be built in Florida. It is a wood frame home with siding. There was a law suit over the siding because it was just detoriating (also something I was not told at time of purchase). I have over the past 10 years gradually replace siding with Hardie board.

I guess I will be working on this for some time to come. Right now, I am trying to find out the cost as I am a single lady and probably will not be able to fix the problem

Hello Again! Mary Ann,

I also live in Florida, Sebring, Florida. I do not live on a flood plain, though many homes locally have been constructed on land historically known to be flood plains. Even though I live on what is known as the Lake Wales Ridge, the ground water table remains around 7 to 12 feet down year round. The surface soil, "sand" gets popcorn dry during the winter and spring months, but this is not enough to prevent moisture from wicking upward beneath any sealed flat surface such as a monolithic concrete slab/foundation.

As for your California construction style of your home, these types of homes are constructed all over the nation. There is nothing wrong with having a wood framed building on a concrete slab. In fact they insulate much better than a concrete block home. I however prefer to construct wood frame homes up on a foundation. This solves the problem of moisture penetrating through the concrete floor. It is also much easier to prevent termite damage from ever happening to the wood.

I purchased the home I now live in for a very good price, with the intention of renovating it and then selling it. As I have stated before, the least expensive way to solve your moisture problem is to pull up the carpet, seal the floor and then add a layer of black plastic visqueen, replace or reinstall the pad and carpet. If they are moldy you should replace them as the mold can kill you! Good Luck!

TMF

For your siding challenges, here is some information:

On January 15, 1998, the Circuit Court of Mobile County, Alabama, granted final approval to a Settlement in the lawsuit known as Naef v. Masonite, CV-94-4033. The Settlement provides a program for eligible claimants to recover the costs associated with damage caused by the installation and incorporation of Masonite Hardboard Siding.

http://www.weyerclaims.com/

Personally, I was able to receive a settlement of about $7,000 to completely replace my siding.

Hi Mary Ann,

I am in the same boat as you! I am following your problem hoping someone can help you which will inturn help with mine. I actually had a contractor tell me there was no way to fix the slab short of tearing the house down and starting over! And of course insurance doesn't cover this. Good luck and if I hear of a solution I'll update your thread.

Perhaps try talking to your nearest home building supply center help desk people. Millions of homes built over the years don't have sealed basements so there are many good quality sealer products available off the shelf because of that.

They do require some prep work of the concrete but they do work well and most people with reasonable hands on skills can do the work them selves as well.

However you will need to strip the basement down to bare concrete to apply it.

Also having a good dehumidifier will help keep the humidity from the air outside from condensing on the basement walls and floor during hot or humid days as well. That could possibly be where some of your moisture comes from if the basement is considerably cooler than the outside or upstairs areas of the house.

Please reverse the case of all letters. And then go back and capitalize the first letter of each sentence that isn't already capitalized. Also please eliminate ampersands from plain text.

Sincerely yours--Editor Crankshaft

Dig a channel around the house and replace with sand if $$$ is short. The deeper and wider the better. Do a section of a few meters at a time, would recommend qualified builder for this task. Determine the lowest spot in the yard and dig a trench there running away from your house also, which will act as a drain directing water out of your property.

Once water issue solved, entire house will need to be "sterilised"...everything (clothes,books etc) cleaned to kill mold.

Place ventilation ducts inside your house that are linked to outside clean dry air.

I agree with DavisRF. You have to determine the cause of the problem before you can resolve it. You don't say whether or not your house has weeping tile. If it does, perhaps it is plugged or the backwater valve is jammed. If that is the case, it may be remedied fairly easily.

If there is no weeping tile and the soil below the slab is sand or gravel, it may be possible to drain the area into a sump pit with a pump to remove excess water and keep the water table down well below the slab. This is not an enormous expense.

Talk it over with a couple of the "bone dry basement" contractors in your area and see what they recommend. It could be that your exterior grading could be improved so that surface water is directed away from your basement wall.

Good luck.

This has already been mentioned but worth reiterating.

It may not be moisture coming through the floor but condensation of humidity onto a cold floor. When we say cold, it means below the dew point for the relative humidity in the room.

My brother had a basement with just flagstones in the centre of London (clay humid soils at 3 metres down). Humidity was a problem if he was to make it an extra room rather than a storage room. With a dehumidifier he was able to make the room into a bedroom. He did have to double insulate the wall with a drain too but as you didn't mention humid walls I am guessing that your walls are not a problem.

Are you rooms well ventilated? This would eliminate the humid conditions and so the condensation to a cold floor.

Finally, to prevent your floor from being cold - if this is the case - you can insulate it with polystyrene and pour screed on top of it.

If you did not have a water proof membranes under your floor then I believe you did not have them under your wall. you did not mention about the type of your house it is double brick wall or timber frame wall? I think you can solve the wet carpet problem by removing carpet and apply the water proof coating on the floor then relay your carpet and that can be done by yourself if you are handy enough or through trade man whatever method you choose try to adhere the safety warning from the label

Good luck

It would seem that you have all the engineering advice necessary so let me just add that depending on when the house was built, when you bought it, and where you live will have an impact on any potential legal remedies. Because "who is going to pay for all this" is going to be a very big question.

I would suggest you find a local PE (professional engineer) in a commercial construction company and ask who their legal firm is.

This is an interesting problem and one that am interested in following to see if an affordable solution is available.

I have often wondered ----- would a combination of self leveling moisture barrier like the titebond products and lightweight concrete help cure the problem. You might loose a couple of inches of ceiling height and doors will need to be adjusted, but the destruction of of the existing floor slab could be eliminated.

One option that might help is to get the slab raised. This is a common pratice in Louisiana. Here is a link to one of the companies I am familiar with here. http://www.cablelock-la.com/ I know there are other methods including injection of materials under the slab to raise it.

I hate the knee-jerk reaction of suing anyone and everyone, but if there ever was a justified situation to do this, now is the time! I would find a good lawyer and have them make the problem go away. Of course this will take time and you have to keep your family's health in mind. Unfortunately, if you are getting moldy wet drywall, you may have a very serious health issue on your hands.

If you built the house yourself, of course you don't have anyone to blame but yourself, and you have just learned that trying to save a couple dollars on moisture protection may cost more in the end... If you hired a contractor to build it and he cut that very important corner, he "has a lot of 'splainin to do - Lucy"!

I agree that the sand drainage "moat" around the house sounds like the best solution to start out with. It will be much cheaper than most of the other options, and it addresses the problem, not the symptoms. However, if you live in a bowl (not a good place to build a house, but they build them below sea level in New Orleans - Oh, yeah, that turned out to be a bad idea, too), you will probably not see much gain from the moat - it will just hold the water long enough to soak in good around all sides of the house. This should be a way OUT for the water - not a way IN.

It might make sense to put in a drainage tile inside the moat, run it to a sump, and then buy a GOOD sump pump to pump the water somewhere else completely. Do NOT allow the water to close circuit and come back toward your moat, or you just solved nothing other than your currently affordable electric bill. Watch that pump like a hawk, and double-check it before any predicted large rains as well as spring thaws.

Again, most importantly I would find a good construction lawyer and put him to good use. There are disclosures that are supposed to prevent a surprise like this when you buy a home, and if you were truly caught off-guard with this problem, then someone lied on a contract, and it should be a pretty cut-and-dried case. It might be the only honorable case he has all year, and it will take some of the sting out of the next year or so worth of expense, hassle, and worry.

Best of luck to you!

Hi

We live in a house built in the late 1700's and abviously this does not have any "vapour barrier" as you call it. The previous occupiers some 23 years ago tried damp proof injection and nearly everything else you cold possibly imagine to try to stop the damp.

When we moved in the very first job we did was to dig all the way round the house and insert a 6" land drain and sbackfill with limestone chippings for about 3" above the land drain. Then simply filled it back with soil. Admitedly it took a few months for it to dry out. Have been here now for 23 years and its as dry as bone.

Does your house have gutters. Some places in the country seem to have forgotten they exist. When you have a one inch rainfall, several thousand gallons of water run off the average roof. If it just drops to the ground beside your house, you will have moisture problems. Gutters and downspouts dont do much good by themselves, you have to add a trench or pipe to the end of the downspout to get the water AWAY, 20ft or so, from your house. We had half a basement wall and carpet getting wet at one of our rent houses. Came over to check on the problem, and found the tenant had disconnected(it was screwed to the downspout) the black pipe from the end of the downspout that led the water away from the house because it was in the way 2 or 3 days a month when he cut the grass. Now, thousands of gallons of water were dumping out the downspout, right next to the house. DUH. Heres your sign.Where do you think its going to go? We kept his rental deposit to replace sheetrock and carpet, and buried the black drain line so the next tennant wouldnt move it. No problems since. Moisture will not "weep" in if it is not present.

Also, the sump pump is a good idea. One nice little 2 foot round hole 3-4feet deep in the corner( or middle) of your basement will allow some of the ground moisture to flow to the pump below the slab level and be pumped out before it gets to slab level.

Digging a "moat" around the entire house also has its benefits, drawing water away from the soil under your slab. Keep this separate from the downspouts system, it cant handle the excess, and will leak right back under the slab. You will be amazed at how much difference just getting rainwater away from your house can make, cheaply. Way better than trying to put a new vapor barrier and slab in, hoping it will "float " above the water you are dealing with. Unless your slab is directly on top of a "wet weather" spring, controling the water outside around your home usually will work wonders.

Mary Ann, WHOA !! Before you get carried away and buy a backhoe, fill your house with flow-able fill or pressure grout your entire slab, stop and consider some things?

#1 Vapor barriers are the easiest things to blame this condition on! Some are not installed, some are under 6 mil thick and not effective, all are subject to rips, tears, plumbing penetrations and improper installation. Almost None are brought up around the edge of a slab.. Are you beginning to see where this goes? Easy to blame it on a Vapor Barrier because you can't see it.

#2 As Davis RF points out, check out the credentials of the people you invite in on this deal. Understand that as mentioned in this thread, concrete is a very porous material with moisture migrating through it constantly.

#3 Identify your moisture content before you do anything! ASTM F-1869-09 is a test to measure vapor emissions from a floor surface. Not too invasive, simple to do and inexpensive. A more reliable test is ASTM F2170-09 that measures the relative humidity inside a slab. Involves drilling holes, inserting a probe and reading the levels after the system is acclimated to your particular home.

#4 "No Luck with a sealer"! There is No Luck involved in sealing concrete! One post offered a particular sealer up as the answer??? Here's the science behind sealing any concrete-- If a product tells you on the label "May be Re-Applied" at a later date! RUN ! Doesn't that kind a make you wonder what happened to the first coat?? If a product cautions you " Do not allow this product to come into contact with Metals or Glass" RUN ! This type of chemistry begins to migrate out at about 6 months and is Totally Gone in 18 months.

In humid, high water table environments your Air Conditioner is dehumidifying an interior space that causes moisture to be drawn up through the concrete Gel-Pore / Capillary system. Seal your floor with the right sealer and go to Hawaii with the money you didn't waste. Look at www.StableCrete.com and make your life simple again. Low VOC stuff for interior uses, applied with a household type Bug Sprayer, can be tiled or coated in 48 hours and has a 15 year warranty for waterproofing!

Good Luck!!

I must have missed your reply that you

a) lived in Florida, and

b) built on a slab, and

c) already have an outside perimiter drain.

d.) cannot get money from the deceased builder's estate.

and you still have rising damp. Clearly my suggestion that you break up the concrete floor is an unattractive option because the floor is part of the foundation.

Now admitedly, once upon a time, I poured a slab under a garage without moving the garage. (It was attached to the house...I could not move it.) I cursed continuously through that job, although do-able, that doesn't mean I liked doing it! On the other hand, it got done. That should be your very last option then.

I have never used vapor barriers in any of the half dozen slabs I poured. I personally have never had any problems with wet slabs. But then, I pay an inordinate amount of attention to drainage, putting slabs on top of compacted crushed rock, backfilling with the crush, and clean sand, making a french drain as you appear to have done. So, if I may be so bold to suggest, there is still a problem with your drainage.

The water table must be very high in your neighbourhood, your house is floating on the water like a ship floats at the dockside. If you dug a hole in your back yard, how deep does it have to be for you to disover it is filling with water? In Florida, I bet the water table is no more than 18 inches down. (half a meter)

If it was a ship, you have two choices...cork up the ship, or drain the dock. That is to say, seal the slab on the bottom, or lower the water table. Corking up the ship might work, (the hundreds of holes drilled with sealant squeezed underneath the slab) and it certainly IS an option. It is likely cheaper than lifting the house, breaking up the floor and doing it right, with all the vapor barriers in place. I hate to comment on that process though since I have never seen it done. It would mean a disruption to your life, you would have to move everything out of the house, and you would have to hire a contractor to do a job which you cannot check on until he is long gone. Sounds like a recipe for strife down the road. Too much can go wrong, and the product literature seems to have words like "May not be the only solution", and so forth. I know that if you drilled holes in MY slabs and tried to inject caulking down there, it would just get lost in the crushed rock down below, and would fail as a solution. Just sayin'....might not work. Or just might work. (flips a coin....) I would rather drain it away rather than try to stop it from getting in.

Water flows downhill. Somehow you got water which is flowing uphill, up through your slab. Thats not natural. (I know, it can act like a candle wick to moisture, the fact that you have tried sealants, and discovered that they don't work, implies that there is still "water in your dock") De-humidifiers should solve any dew problems. Tape a microscope slide onto the floor, and see which side collects the moisture. If it is the side against the concrete, you have moisture wicking in. If you have moisture on the outside of the slide, you have a dew problem. Often dew can masquerade as invading moisture. Make sure you eliminate this possibility....a dehumidifier is a lot cheaper than a new foundation, and it behooves you as the one who writes the cheque to be sure!

If you can't cork up the ship, the other option is to "drain the dock". If the backfill was done with crushed rock, as your answer suggests, then the dock has already been drained. Why then, is there still water in it? Water has to have a place to go. Water has to have a way to get there. Too obvious? Not really. My vapor barrier-free slabs are dry because I imagine myself as a raindrop, and I think about how I will get from the roof, down the spout, into the ground and flowing away from the property, and make it easy to get there.

A reasonable and inexpensive solution would be to lower the water table under your house. That means a drain all around the outside, a sump well for it to drain into, and a sump pump to keep the drainage working. Up here in Canada, the sump pump must be inside the house. In Florida, you can use an outside sump...a further savings! The concrete will then have no water to "wick up", and of course, no need for any sealants, either inside or outside.

Any other solution would demand this one to implimented first, so it is a good first step. This is the least expensive solution, and may be all you require. You say you have already done that? Then the question is "why is it not working?" Perhaps your trench was not deep enough to be effective. Perhaps your sump pumps are not installed or turned on, or working, or installed on the high side of the property. Perhaps the downspouts are not directed far enough out from the walls. Perhaps they need a fabric covered perforated plastic ABS pipe in the bottom to seriously move the water. Perhaps they backfilled with clay instead of crushed rock or sand. Look outside for the problem.

I am a little curious about your engineer's report. Why did he recommend removing the slab instead of digging a deeper trench around the property? Seems odd to me...and odd to you too, which come to think of it, is why you asked the question in teh first place.

Good Day Yousef1,

I am a retired Residential and Commercial Building Contractor living in Florida. I have learned that it is wise to put a vapor barrier beneath all concrete placed on grade. The primary reason for this to prevent the water in the concrete from being sucked into the ground below causing early curing of the mix. The concrete will hydrate with or without the vapor barrier, but without it will likely not achieve it's intended strength and is more likely to crack in the weak areas sooner. Plastic is cheap, concrete and labor are not.

TMF

Up here, we flood our slabs like skating rinks, always making sure there is a film of water on it for at least the first four or five days, and wet down regularly for a couple of weeks after that. If there is too much water,(ha!) the slab just spits it out the bottom. We don't want vapor barriers here because that might trap moisture in the concrete and result in spalling when it freezes. I have heard that they are bringing in a "vapor barrier" requirement Not a problem in Florida I bet!

As a contractor in Florida, you know then if it is code to put plastic down before the pour. Sounds like it is sound practice, whether or not it is code, because after all, you have that hot Florida sun which would parch the concrete pretty quickly and letting your concrete set in a plastic bathtub makes for good concrete! Anyway, whether it is "code" or not, the fact is the lady doesn't have a vapor barrier, and has to live with that.

(I know that I have never used a vapor barrier, and my slabs are hard, solid and dry. Might be different in the sun! OTOH, I pour them inches thicker, use double re-bar and fiberglass entrained concrete, so maybe I am not typical. For outdoor slabs (like sidewalks) I use air entrained concrete and never vapor barrier them. I mention this only to point out that thousands of slabs have been poured around the world without vapor barriers with little or no consequences. Normally not even wicking of moisture up through the slab, though I remember one time....... (insert vacant gaze here...grin!) I am sure that you have plenty of horror stories though, and I really want to hear them!

Actually, over the years, I have placed and supervised the pouring,"placing" of many thousands of cubic yards of concrete of strengths varying from no discernible strength such as flow able fill to strengths exceeding 6000 psi. As you know, concrete placed on a tight clay compacted fill is not going to suffer from having the moisture flow through the substrate as if it were a sand. However if moisture can some how find it's way through the compacted material, traffic on the concrete will cause it to function like a diaphragm wicking water upwards until it puddles beneath the concrete. This is when it begins to crack and disintegrate. There is not many kinds of places that I haven't placed concrete. I guarantee you three things about concrete. It will not get hard when you want it to, It will get hard before you want it to. And it will crack! If you want to avoid the cracking of concrete, "don't add the water"!

TMF

This is all getting a little too esoteric for me. If it was my single story wood frame house, I would jack the whole thing up, seal the slab, and add pressure treated joists and a wood floor. Ventilated of course.

Hey, here's a suggestion (not sure if it will help). You may be looking for a waterproofing company. If there are cracks or holes in the foundation of your house on the outside then that could be where the moisture is coming from. In this case you would have to contact a home waterproofing company. My husband did this professionally for 5 years. Basically, they dig out around the foundation of your home and lay water barriers and weeping tile to direct water and moisture away from your home. The company he worked for would sometimes have to reinsulate the interior of basements as well but I think that was because the insullation that was there was deteriorating from water damage. From what I understand this whole process is pretty pricey but effective since I'm pretty sure it's law in Canada now that any houses being built must be waterproofed.

Ordinarily, I would wholeheartedly endorse this suggestion. However, this house is built on a slab, so there are simply no basement walls to waterproof. That being said, if there is any part of the joint between the wall and the slab which might leak, a waterproofer could make sure that that joint is secure and properly flashed. And a basement guy might not think to check the bottom of the walls for flashing, a waterproofing guy surely would. So, because you suggested an alternative professional to look at the situation "on the ground", I award you a "good answer".

Go back to the structural survey of the house that was carried out before it was purchased. There may be a claim to be made on the surveyor's professional indemnity insurance that may cover the cost of carrying out the remedial work.

Do turn off Caps Lock before making a claim, though.

I have a similar problem, there is dampness under my floating slab, however I do have a 1mm plastic waterproof barrier under the concrete. The water is penetrating the slab in two areas and the sand under the concrete is saturated. The ground round the house is wet most of the time, but the bottom of the concrete is about 150mm above ground level on one side of the house. If I cut out two bricks and drove a 100mm slotted pipe through the sand under the concrete would this offer a way out for the water??? this has been driving me nuts for years. oneth

Hi,

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