Concrete Wicking

Some additional information about your site would be helpful.

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Where are you? What are the typical weather extremes for rainfall and temperature?

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What type of soil/ground exists outside the fill?

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Do you notice water accumulating in the area between the house and the rock wall when it rains?

water table level would be helpful.

I am not sure. But soils report did not reveal water in the three 20' deep bore holes.

Are the test bore holes by any chance done close to where the moisture are now present? Since a lot of underground streams are present in the Manoa Valley, it may also be a case where the natural flow path of these streams were blocked during constructions? Once blocked it is only natural for the stream flow to seek other way? I experienced flash floodings coming from these streams when I was along in the Manoa Rd., not far from the University when this was observed.. and seen a lot of cars swept and damaged properties caused by these streams..

We are in Hawaii. I am at the 500 foot elevation. Weather is mild, 60 to 90 year round. We get a fair amount of rain on this hillside of Manoa Valley.

The soil report commissioned for the construction indicated that the soil was volcanic silt and rocks, not clay. We bored down something like 20' and did not encounter water. The site was bored in three locations. Outside the fill is the same stuff.

I have noticed during heavy rains that water does accumulate between the house and rock wall. But it eventually drains away after an hour or so.

Would anyone have information on good electronic meters for taking moisture readings?

Here is a cheap one that Lowes sells...

http://www.lowes.com/pd_78059-56005-MMD4E_0__?productId=3136919&Ntt=moisture+meter&pl=1&currentURL=%3FNtt%3Dmoisture%2Bmeter&facetInfo=

"I have noticed during heavy rains that water does accumulate between the house and rock wall. But it eventually drains away after an hour or so."

I would suggest not to do any inside fix yet until the outside problems has been addressed...

The basement of my house in New York has had water problems too before although it sits almost on the top of the hill! I implemented the following steps which proven to be very cost effective in correcting my wet basement problems;
1. All water runoffs coming from the roofs were re-directed away from the house. Ensure no standing water accumulates even when continuously raining.

2. Made a small trench in-between my property and my neighbor's since his is a bit higher than my own! Any collected water are drained away from the house, always flowing! ensuring No standing water whatsoever!

3. Then made the area of about 3 feet wide from my house walls, around the immediate perimeter of the house to be slightly higher and graded down away from the house..

4. Poured a concrete walkway with a bit of slope around the perimeter of the house. 5. Lastly was to water sealed all basement windows.

I'll be brief(because the text editor doesn't agree with my phone browser).Even though the soil drains well enough (and property is sufficiently above water table) to preclude standing water from the boreholes, surface tension can allow significant amounts of water to remain i the soil and to be laterally transported..The hill and wall may be more important to this problem than it might seem at first glance. The amount of rain that streams down the incline and ends up pooling on the surface between the house and wall is probably minimal, most of it likely seems into the hillside quickly.... which presents a different problem.As that water that falls and seeps into ground uphill from you, it likely creates a subsurface flow downhill through your property. Even while air can be incorporated in the soil, the height of the water in the soil uphill cab still drive water laterally against and under your property..This could mean that even after you take care transporting the rain that falls between your house and wall to prevent any pooling there, a significant flow could exist beneath the surface to your foundation when it rains heavily. .The levels at which water flows horizontally and accumulates are not typically at a specific elevation relative to sea level. Instead water table and the flows occuring with significant rain, tend to follow a path more related to the surface and any significant geological features. When the side of a hill is cut sometimes streams will pour out places in the cut when it rains. The very same thing could be happening at your property, though the well draining sand would make it difficult to notice..So in addition to the good advice you have already received in the other comments, here are a few additional suggestions:.The rain falling on the your house's roof can be significant. Make sure your gutter or other system effectively collects that water and extend if necessary drain lines to release to an area distant and downhill.It is probably fair to assume that in heavy rains water is flowing towards your house in the ground between your house and the wall. This suggest a modified approach to french drains may be appropriate, with the pipe still layed at the bottom of a ditch (of increasing depth for drainage), but instead of merely surrounding thee perforated pipe with coarse aggregate and the burying it all, instead one side of the ditch is lined with an impermeable barrier and a geotextile lines the other with something between hydrophobic or at least that provides good drainage and support, so perlite or airy lava rocks perhaps.Generally try to have surfaces slope away from your house. It may be beneficial to make those that slope away less permeable to water for soil consider hardpack a layer of clay and iron oxide...maybe a little below the surface. For concrete with appropriate grade, Sodium silicate solutions are far less expensive than concrete hardener/sealers though is is often the exact same thing.For surface that for some reason slope toward your house, you probably don't want to decrease permeability unless you are moving the water to a drainline closer to the house.get a stand alone dehumidifier...these can be very helpful for dewatering/drying when used in combination with a decent fan.I really hope this doesn't format to one big block again...sorry if it does..

I had a friend that mentioned: the hill absorbs water above out house site during rains. As it travels down through the hillside the water exerts pressure and looks for a way out of the hill. Like a water hose filled with water, if you elevate one side (like upside of the hill) and release the end, the water gets pushed out the lower side. I am thinking that is the surface tension thing you are mentioning.

The hill is about 1500' tall. I am about 600' up the hillside.

The home has rain gutters, so much of the rooftop rain is diverted into underground pipes off the property. The home also has a concrete walkway 30" around the house.

I will google the internet for this type of modified drain system you mentioned for more information.

Thank you.

It sounds like your builder or the guys that poured the slab left off the moisture barrier.

Before you do any digging, you are going to have to have a moisture barrier anyway, which at this point, will involve pulling up all of your flooring and laying down 6 mil plastic, so I would do that first.

After that, look online for methods of laying flooring on concrete basement flooring. It doesn't sound like you have a flooding problem...just wicking or condensation, which trenching won't fix.

I have heard from the flooring guy that two coats of epoxy will provide 20 or so lbs of protection. I would do that, but also try to get the water away in the first place.

When you say wood floors- do you mean hardwood, or wood subfloors with another (including hardwood) floor finish on top? It sounds like part of your problem may be the way the floor was installed.

If it is hardwood, it should be installed according to standard procedures on a system of sleepers with proper 6 mil vapour barrier underneath- was that done?

An alternative is to use engineered hardwood, which has the cosmetic wear layer laminated onto a dimensionally stable substrate.

I do mean engineered hard wood flooring. It is a top layer of real wood with several layers of ply substrate bonded together. Below the engineered wood floor are two materials, 7 lbs moisture barrier and a cement leveler placed on top of the concrete. Another flooring company has said that they use two coats of epoxy in cases like this. I just don't want to take their word for it anymore.

did you start out with proper foundation drainage including building site drainage?

If done per plan then yes. I am not sophisticated enough to have know during construction.

The contractor should have dug a trend trench before the foundation was poured.

This is standard procedure on houses dug into hill sides for rain drainage, but maybe you live in the desert?

It sounds to me like you've found one of the reasons your builder went out of business.

Hire a certified civil engineer and a lawyer. You may not have any financial recourse directly against the defunct business that was your builder but let your lawyer advise you about this. Your lawyer should know the relevant laws of your location and what legal actions can be taken. Your lawyer should also know what municipal inspections the builder should have performed to build this house.

You should have a moisture barrier under the concrete slab. If this wasn't installed, you have a problem. The calcium chloride test is not reliable when testing a covered floor; in other words this is a test performed before the flooring to determine moisture content. If we assume that the slab was installed properly and has a moisture barrier, then there may be a leak in the plumbing that is causing moisture accumulation in the slab, so this would be the first thing to check. Cut off all faucets, make sure no leaks, shut off ice maker and see if meter moves over the course of an hour or so, look around toilets and plumbing locations for any drips or moisture. If you find a leak, then that is most likely the problem.

Thank you for the comment. I agree, we should have a moisture barrier as it is on design.

The calcium test was performed by pulling up two 3 sq ft sections of floor, removing the leveler and 7 lb moisture barrier which exposed the bear concrete. So the test was not done on the wood flooring material, but on the bare concrete.

I shall try to the water leak test. Thank for the that tip.

<I have heard from friends to dig a trend all the way around the home 3' deep and drain it out to the front of property>

THAT is Surely the way

The footings are to be dug three feet deep so that was the reason for the depth.

I do have a concern that the drain will fill with silt and roots eventually becoming ineffective. If there is a way to make a drain with "sewer traps" so I can periodically snake it clear of dirt and roots that would be good. I just don't see anything like that on the internet.

I will need to start looking for a hydro engineer but don't know any at this point.

Special large bore plastic pipes are used with holes in the top to capture moisture. A filter "fleece" covers this holes to prevent other stuff entering. It works fine in such situations here. I did two sides of my house 8 years ago, fantastic....

this is what Andy is referring to.

http://www.lowes.com/pd_308700-676-EZ-0802F_0__?Ntt=french+drain&UserSearch=french+drain&productId=3136611&rpp=32

The moisture test is telling you 13 lbs of moisture emitted over 1000 sq ft per 24 hrs your limits are 3-5lbs. Sounds like your sealer failed. Check with a professional floor installer before ripping up the concrete or your yard.

Another issue may have happen the builder before applying the sealer for the floor may not have tested the moisture of the concrete plus if the room humidity was high and the build sealed the floor it could have saturated the concrete holding in the moisture causing the floor to buckle over time. At 13 lbs there is no way you can at this point seal it you most dry out the concrete. Again I'd contact a professional floor installer.

They did not test the floor but assumed the 7 lbs moisture barrier was sufficient. One installer recommeneded two coats of epoxy. I think that I need to pull up the entire floor and not just the areas where the floor buckled up from the concrete. This would also "dry" out the concrete as you mention here.

Thank you for the comments.

I think I will try to get the moisture away from the home with a drain and also use epoxy on the floor. The question now is how to make a drain that is maintainable. Also, since my 3' deep holes do not have any water in them, is it going to be deep enough or totally ineffective.

I have a slab on grade home with no basement. So I do not think I can do an internal drain system.

There is perforated flex pipe sold at your local hard where store. This is called a french drain. You'll need to dig down about three feet and three feet away from the house fill will 1/2-3/4" crushed stone all around the pipe. Then cover the last 6" with the surrounding soil. You can "Google" for a better explanation.

I am told by my Howlie wife that many houses in Hawaii do not have AC systems (I've never been there but is on the bucket list), but in your case an AC system would go a long way towards dealing with humidity issues.

Do they have "swamp" coolers? They're pretty common here in AZ, mostly older homes. I'm not overly farmilar with them but the basics is they add cool moisture to the air with a fan. This helps bring down the temps. In Mexico along the shore line they use the breeze to keep things cool but again you still have realitively high humidity.

nope, swamp coolers need dry air to work which is why they work in AZ. They don't work where the humidity is high enough to make you feel like you need SCUBA gear to breathe. =b

Hawaii being an island in the south pacific is VERY humid....

I guess thats why I never say them in the North East. ; ) Here we have standard AC units on my place and I was told by one of the guys at work with not to install swamp coolers because they cause more trouble then they are worth. Some I guess have a tendicy to leak and cause water damage and mold in your roof. Also they tend to attached bees hives because of the water source.

We do have AC. But as the temp rarely a problem we only use it 3 or 4 days out of the year. We have a steady wind and the home has many windows.

it isn't about temperature, it is about dehumidification.

You may not have a water problem. You may have a humidity problem. They are not the same thing because humidity in the ground or concrete or air moves in very different ways than water does. Also, engineered flooring, All engineered flooring is extremely sensitive to humidity. If the humidity in the air in the ground is higher than the air in the house, which is normal, then there must be an "intact" vapor barrier between the concrete and the floor. In respect to Boyles laws of vapor pressures even a pinhole can defeat the barrier.

When the flooring company came to repair the buckled portion of the floor, the took up the floor and there was water droplets on the barrier. They scraped off the glued down/moisture barrier from the concrete and again it was damp and had water droplets. That is when they decided to glue the plastic shell thing to the concrete with the calcium inside to take a measurement.

They did provide a gap (looked like 1/2" or so) at the edges for expansion.

I agree with all of the sound advice about moisture barriers and vapor coontrol but do not overlook the simple expansion and contration of the floor itself. When a wood floor is installed it needs some extra area around the perimeter to allow for changes in size due to expansion and contraction caused by temperature changes. You say that the temperatures changes from 60 to 90 degrees and that is enough for the wood to expand. If the installer did not leave enough room against the walls the floor will buckle when it expands. This gap is usually covered by the baseboard at the walls.

Don't know if anybody's mentioned this, but if the air in your house is kept very dry and the air under your floor is very moist, the wood will swell on the moist side and shrink on the dry side. This would cause the edges of your floor boards to warp upward.

There were previous threads of this kind. One involved a pipe buried in the concrete floor that was leaking. Look for plumbing leaks including around the furnace if it has a humidifier. Check in several parts of the home to see if it is wet averywhere or just in one general area.

We had the same problem when I built my underground house and found the problem was the floor installer had not let the flooring season inside the structure long enough so it acclimatized and did not swell when it reached the humidity levels inside- we solved the problem by lifting the borders of the flooring and letting it subside then cut the edges to fit the new profile- - hope this helps

In addition to installing a "french" drain system arround the perimeter of the home I would suggest you install rain gutters on all of your roof edges if you do not already have them.

If the water/moisture barrier is properly installed with no leaks present then the back side of the moisture barrier will be wet but the front side contacting the wood will be dry.

I would also check the installation clearance between the flooring materials and the walls.

All wood and composite floors require room to expand around the entire perimeter.

If this clearance is not adequate, the floor will buckle with the degree of buckling depnedent on the amount of relative humidity present.

Also; The moisture barrier must wrap up/around the edge of the flooring so that none of the floooring contacts the concrete cement.

If all of the above does not solve the problem, I would suggest you remove all of the flooring then clean and paint the cement slab surface with a flexible, high quality floor paint and re-install the flooring following the manufacturer's directions.