Damp coming from sub floor

Hire an engineer. The engineer is retained to protect the builders interest, so his report will range from minimal proposed mitigation to blatant under reporting or misreporting (speculative) of primary cause (and therefore financial responsibility). You should line and be prepared to bring in your own Geotechnical engineer. If there is a timeline issue, bring your engineer in sooner so he can conduct his own studies and prepare an argument in support of your case. Since any substantial repairs will be expensive, the contractor is going to try and avoid fully repairing the problem, and seek some cheaper minimal solution that creates the perception of an adequate attempt to repair the problem. you are at the point where you need a technical professional with no liabilities in the project to represent your interest.

Fairly easy to totally rectify via the use of capillary crystalline reactive technology.

www.xypex.com

www.kryton.com

THis will permanently resolve the moisture issue and thus also the mold.

he could dump a few tons of Dehydrated lime under the house .

FYI, it is hydrated quick lime from adjacent soils and the concrete that leads to efflourescence at the concrete surface. Also, Lime is about 1,000,000,000,000 times more soluble than the silicates in portland cement.

Please tell us more about this technology and how it might be employed in the present case.

Sorry for the delay--Ike knocked the power out for a while.

Application onto the concrete imparts a crystalline growth wich migrates up to 18". Thus, you seal the concrete from the negative side but the crystals grow to the point of ingress and seals it there. It is not a "coating" that relies only on adhesion.

The concrete can still breath as the dendritic fiberous crystals allow air movement but not water.

The process is permanent and will work against hystrostatic pressures . It strengthens the concrete and restores the proper PH

It must be installed as per instructions to the raw concrete--not to other attempts or to painted surfaces.

I have had great success on big box stores by drilling holes on a 12" grid and installing it as a plug in the holes. The crystalline growth radiats out and resolves the moisture or vapour transmision.

Hello Guest,

If you have found this technique to be successful, it is certainly worth a try, but first, there must be an assessment of the problem. For example, if the problem is rainwater or spring runoff draining into the heating duct, your solution would not be very helpful.

It seems to me that the first thing to do is to carry out a thorough examination of the site and try to determine the source of the condensation. This must be done by someone who knows what to look for.

And further to the comment by RCE, the occupants may be well advised to seek alternative accommodation pending a reliable diagnosis of the problem.

I have found this to work 100% of the time when it is used according to the instructions.

Of course the cause must be determined first. Also,since it will withstand up to 405 feet of head pressure, drainage must be addressed if the cause is a spring or a leak.

I once waterproofed a CMU wall and resoved the water coming into the basement. I was told the water supply had been replaced to the street.

After a month water started bubbling up outside the wall. THe application had stopped the water from coming through the punky concrete (concrete blocks) but, of course did not fix the leaking pipe that was the source of the water.

Anyone versed in Negative side waterproofing materials and techniques will know what to do.

After a month water started bubbling up outside the wall. THe application had stopped the water from coming through the punky concrete (concrete blocks) but, of course did not fix the leaking pipe that was the source of the water.

Sounds like risky business. Shouldn't there be a relief mechanism somewhere along the line? A "punky" concrete wall that won't leak sounds like a disaster waiting to happen. We had flooding here this summer and several people with concrete block walls pumped out their basements too quickly and the hydrostatic pressure found the weak spot and blew the wall in.

Sorry to "muddy the water" with the use of certain terminology.

In my opinion all concrete blocks are "punky" concrete.

#1 The average of any three has to be 1900 psi---very low by poured concrete standards.

#2. Even if the block itself is 8" or even 12", the wall thickness--the part holding up your house or resisting the lateral forces of the dirt, is only a little over 1" thick.

Your input about the walls bowing in after the water was pumped out proves my point. Blocks are barely sufficient to hold the vertical loads of a wood frame house. They cannot resist a full plastic head when the exterior dirt becomes completely saturated. ( When the water was on the inside the pressures were equalized)

That leads to your other point about the need for relief. That is exactly what I am saying when I say there must be allowance for drainage. Drainage provides pressure relief. Standing water is much more of an issue than running water. Concrete block walls--and some poured concrete walls for residential are not designed to be a dam. They are mostly OK for the vertical loads. The plastic soils loading does not presume full plastic head.

Hmm, interesting. As an engineer, i would normally presume these were structural components and the block cells would be filled with grout (typically a low strength pea gravel concrete) and steel reinforcement. Thus a 12" block wall would provide greater resistance to infiltration. All constructed walls should have some drainage built in at the foundation level to stop water from damming, however water moves through block walls even in conditions of unsaturated flow in the materials behind the wall. The movement of water is what leads to the infiltration of hydrous lime through the wall to the surface of the block, "efflourescence". In no way should a house (or anything structural facility) be structurally supported on empty celled concrete block (maybe a mobile home could as a temporary solution). FYI the soils test for angle of friction and plasticity are conducted as saturated conditions, so it does assume the weakest soil strength (at saturation) and an overburden. What is not assumed as a pressure behind a wall is the water pressures for full saturation, if the wall is drained.

Actually what i think you mean to say, instead of unregulated as every state has regulations for engineering of CMU walls in-place, is that in many jurisdiction the regulations are not adequately enforced. It is different to say there is no law than to say ther eis law and no one obeys it. As I had indicated, they soils are tested at the weakest saturated condition, this is not the same as the walls supporting a fully saturated soil load. The walls support the saturated soil itself, but as indicated previously not the pore water pressures. Thus soil "plastic" loads are not the concern, but rather the water pressures in saturated soils. And having spent years conducting special inspections of concrete tilt-up and CMU walls, I do realize void occur in the grout in CMU, as well as rock pockets and weak pockets in concrete tilt-ups. The strenght of a CMU wall can exceed the strength of a concrete wall, it just depends on the thickness and design of each of the walls.

sell it move!

One problem is that the husband cut the concrete floor. Renters are not normally expected to do that.

Or do you own the property?

Is there a lease or security deposit?

Location?

Depending on these answers, moving may be the best option.

No dpm? Mossy, wet ground? Get an attorney involved soon. Keep a daily log of all conversations and get everything in writing. You may also want to get a medical baseline established for your family if you intend to continue to live there while you resolve this.

GA.

I have a similar problem with an old concrete poor before vapor barriers were available. I think a 12 mil sheet laid on the thoroughly clean slab then 4" polystyrene foam then float a fresh poor should correct the dampness, I intend to try it.

GETTING MOISTURE OUT OF BUILDING THAT SET ON CINCRETE CLABS IS A BIG PROBLEM EVERYWHERE I OWN 3 LIKE THAT.

THEY MUST BE SEALED GOOD ANY WHERE WOODS IS USED ON THE SLAB YOUR GOING TO HAVE PROBLEM WITH MOISTURE.

AIR CONDITIONING IS BEST WAY BUT USUALLY TAKES 2 OUT SIDE UNITS TO HANDEL THE MOISTURE ESPICALLY WITH HIGH HUMIDIDTY.

An engineer sent by the builder will have only relative (to his integrity) independence. Keep a written record of all discussions, and keep an attorney's phone number handy.

The amount of condensation you describe suggests another possibility which I have seen only once before. Ducts around the exterior of a building below the floor slab were encased in concrete. Water was somehow getting into low lying areas of the duct and hot air was constantly flowing over a pool of water resulting in extreme condensation in the building.

I agree with those who say the problem is potentially very expensive to fix. You certainly need someone knowledgeable in residential construction to represent you at any discussions which may take place. You may need a lawyer as well, but that can wait until you get a better handle on the problem.

You can get quite a lot of information from the internet on the subject of mold. There are several good articles at this site. This document is put out by the Environmental Protection Agency and is well worth reading. If the mold is as bad as you have described, you should seriously consider making alternative living arrangements until the problems have been rectified.

It is such cases of ventilation air flow over standing stagnant water that lead to outbreaks of legionnaires disease.