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KEJR
09-30-2011, 04:56 PM
Hello,

I have a garage that is halfway built into my basement and that is where the machine tools are. Every year white and pink deposits come out of the concrete right at about or just below ground level. I am fairly sure it is salts and other things from the concrete coming out slowly with moisture coming in the basement. Please note that there are no signs of actual water coming in through cracks or anything of that sort. Besides making a mess of powder all the time I am concerned with long term degradation of my foundation.

Has anyone here had luck with the Drylock type products made for painting concrete walls? I am thinking to paint the walls to keep things bright and tidy. I just don't want it to peel where the moisture is slowly coming in. Any ideas are welcome.

Thanks,
KEJR

Oldbrock
09-30-2011, 05:05 PM
If you are going to do it right you have to dig up all around the basement wall and properly seal it on the outside and redo the drainage from around the footings. See your building specialist about wall preperation and coatings to do the job. Big job. I'm glad it you not me. :eek: Peter

The Artful Bodger
09-30-2011, 05:21 PM
I have no idea if this would work but years ago I saw someone suggest drilling holes in a wet concrete wall and injecting an oily substance that would spread between the ground water and the concrete eventually to be soaked into the concrete and making it water repellent. His suggestion was used motor oil.

Are there any comments on this?

Mike Burch
09-30-2011, 05:53 PM
Not sure about concrete, but one of the brick houses I lived in while in England had a dodgy damp-proof course, bringing the possibility of rising damp. This was fixed by drilling into the bricks and injecting a silicone of some sort.
Try your local concrete driveway sealing guys for ideas. I would be very leery of a DIY fix like injecting old sump oil.

gwilson
09-30-2011, 06:28 PM
Such oil gets into the ground water,too. It will show rainbows on nearby ponds. If you have a well,I'd NEVER do this. I have a well,and never pour anything on the ground that I don't want to end up in my drinking water.

Duffy
09-30-2011, 06:50 PM
AB, that treatment falls right between bat snot and dragon blood and is as effective. The external treatment is probably the best, (AND the most expensive!) Another treatment that will work, if it is not massive leakage, is to paint the concrete with either Potassium or sodium silicate solution. Check with National Silicates for more information, but it is comparatively inexpensive and within the range of DIY. There IS a chemical reaction-this is not witchcraft.

Gravy
09-30-2011, 07:03 PM
I have no idea if this would work but years ago I saw someone suggest drilling holes in a wet concrete wall and injecting an oily substance that would spread between the ground water and the concrete eventually to be soaked into the concrete and making it water repellent. His suggestion was used motor oil.

Are there any comments on this?

I've got a comment.

Really REALLY BAD IDEA!!!

Don't do it. The oil will go everywhere except where you want it. You will still have a wet basement, and you will likely get a visit from the humorless folks in charge of ensuring that your drinking water isn't contaminated with used motor oil. Getting that oil back out of the water supply may well cost more than you will earn in your entire life.

MichaelP
09-30-2011, 07:05 PM
If you are going to do it right you have to dig up all around the basement wall and properly seal it on the outside and redo the drainage from around the footings. See your building specialist about wall preperation and coatings to do the job. Big job. I'm glad it you not me. :eek: Peter
Absolutely. Don't waste your money on anything else. All those internal treatments are just temporary Band-Aids, at the best. I have recently went through this adventure and am very happy I've done it right.

JoeLee
09-30-2011, 07:11 PM
Sounds like who ever poured the floor never put poly down first.

JL..............

The Artful Bodger
09-30-2011, 07:49 PM
Ha ha, I did not specifiy old engine oil as the only potential injectable substance.:D

Cheeseking
09-30-2011, 08:23 PM
That sounds like efflorescence (sp?) Water vapor passes through concrete almost as if if we not even there. IIR it's capillary action that will drive it from high RH to low RH so a Membrane or sealer on the outside of the foundation is probably the only way. Anything on the inside will probably bubble and peel from the vapor pressure. Builders at least around here will spay a black tar residue to the outside foundation walls prior to back fill although I suspect they use bare minimum thickness to save cost. If I was to build again I would double up the coating or use the best available coating system and insulate with polyiscoanurate foam.
There may be some concrete sealer that claim soaks into the pores and stops the chemical reaction converting the minerals in the concrete, salts etc, and seals the pathways for water vapor but I'm not sure if they work or how effective they are.

lynnl
09-30-2011, 08:42 PM
I don't think water (moisture) can EVER be kept out permanently, from a treatment on the "dry side." Sure, it may work for awhile, but eventually the water gods will triumph.

MasterMaker
09-30-2011, 09:30 PM
I would go with Duffy here since I have used this and it works.

Potassium or sodium silicate is used to waterproof brick, concrete and ceramics.

If my memory isn't of it crystallizes into non water permeable crystals when it gets in contact with an alkaline.

If the floor is bare concrete so that the silicate will get absorbed deeply into it, its should stop the moisture intrusion(or at least drastically improve the situation with a couple of treatments).

It is sold commercially here as a waterproofer for stone and concrete and I know its is a very old remedy for moisture problems.

I haven't got a clue if it is sold as something other than the chemical where you are but it is cheap here so the same should be true where you are.

Iraiam
09-30-2011, 09:59 PM
How about mineral oil, I have used it to water proof other stuff like gloves, boots, I used it on a horse saddle once with good success, never tried it on concrete though.

CCWKen
09-30-2011, 10:15 PM
How about mineral oil, I have used it to water proof other stuff like gloves, boots, I used it on a horse saddle once with good success, never tried it on concrete though.
Mineral oil is made from petroleum (oil). :rolleyes:

Pumping a petroleum product into the ground in Texas will get you a 10 year "vacation" and cost you about $10,000 per day that it remains there. If it enters an aquifer, you'll probably never see the light of day.

boslab
09-30-2011, 10:44 PM
the injection method of waterproofing [evidence is conflicting if it does completely stop RISING damp] relies on the injection of silicone oils into the porus brick/mortar/concrete block/mortar, the building reasearch establishment in the UK wanted to varify the effectiveness of this method as builders were running amock with moisture meters and scaring the hell out of householders who unfortunately new no better than to listen and purchase useless treatments of dubious effectiveness.
they built walls in a tank of differing matirials eg, cinderblock. autocleaved areated thermal block. engineering brick, common clay brick with differing martars, old fashioned black mortar, inc hydraulic lime, lime portland cement, plain portland, sulphate resising portland and so on.
the tank filled to below dpc to measure how the wall performed. no rising damp
above dpc, little or no rising damp.
it would seem according to them that rising damp in all but a few unusual cases does not exist.
it was however found that penetrating damp does exist and 9 times out of 10 was misdiagnosed with a moisture meter,
it was also found that walls that are cold condense water and that the wall will get damp as the water condenses, this can be below the surface and the wall can feel dry however this wet layer called interstitial dampness can move laterally through the wall depending on hydraulic gradient, it can present at the surface and result in effervescence of sulphates [white/pink fluff]
you must take precautions on the outside to prevent the penetration of water, if not possible then tank the inside with membrane or the newer tanking cements eg
http://www.constructionchemicals.co.uk/acatalog/tanking_products.html
also prevent moisure laden air access to the wall with membrane and importantly insulation to prevent condensation.[use solid insulation not rockwool or glass as it wets nicely. polyurathane is preffered over here]
it can be difficult with below ground walls, i've even seen a hole cut through the wall and a layer of dirt mined away! by hand! [best left to professionals i reckon]
in short, tank and insulate if you cant clear the back, injection dosent really work, injection of mineral oil does not work at all as the water is able to move it in front of itself as it progresses,
hope you solve it, get someone in from the building department of your council to have a look, the service is usually free as they want to stamp out unscrupulous 'tradesmen' who offer ineffective treatments and no cure,
all the best
mark

PeteM
10-01-2011, 12:12 AM
For new construction, carefully applied Bituthene is probably the best treatment.

Your case doesn't sound so severe that it's worth digging up the foundation to stop a bit of efflorescence. If there's a humidity problem, a dehumidifier with an automatic pump (seal up the garage) would likely be all you'd need.

On edit: I've seen thick epoxy coatings stay put if there's only slight hydraulic pressure. This might be an answer to the cosmetic issue.

kendall
10-01-2011, 04:28 AM
What kind of rain gutters and downspouts do you have?

At or close to ground level sounds like surface water which can normally be eliminated with gutters and down spouts.

garage that's halfway built into basement sounds like a hill, and I'd guess it's the high side that's gets the deposits. Preferably, dig a trench on the high side with at least one end leading to the low side, a U with both ends to the low side would be best. Dig it 1ft w x 2ft deep, fill 3/4th with pea stone, and cover back up. If you'd rather, you can go with perforated drain pipe which will be a bit cheaper material wise, but the trench/gravel will handle more water and have a wider/deeper 'catch' area.

Alternate, possibly the best, would be to trench at the foundation two or so feet, spray bitumen, then fill mostly with gravel or use the drain tile.

With either make sure the trench or tile lead to a low spot.

tlfamm
10-01-2011, 08:56 AM
For new construction, carefully applied Bituthene is probably the best treatment.

Your case doesn't sound so severe that it's worth digging up the foundation to stop a bit of efflorescence. If there's a humidity problem, a dehumidifier with an automatic pump (seal up the garage) would likely be all you'd need.

On edit: I've seen thick epoxy coatings stay put if there's only slight hydraulic pressure. This might be an answer to the cosmetic issue.


The best interior solution is probably as you suggest: a dehumidifier.

But what about the outside? Is the landscape grade around the structure a contributor - and what about roof runoff? A variety of solutions are possible in those cases, some more painful than others.

For a very good-quality dehumidifier, check out the Santa Fe line. I have the "Compact" model in my 700 sq-foot basement, purchased from Thermastor. American made, the price is 4 or 5 times the cost of a big-box cheapie. So far (1 year) I'm satisfied with the unit, but the price does sting:


http://www.thermastor.com/Santa-Fe-Compact/



---------------------------

Currently I'm working on a master's degree in moisture infiltration into my home. I may be eligible for a Phd in the subject :(



Edit: fix link above ...

SteveF
10-01-2011, 08:59 AM
I had a house with a humidity problem in the basement and white efflorescence stains on the walls. Scrubbed the stains off with a wire brush and muriatic acid and painted with the oil based Drylok. Definitely lowered the humidity but over time (maybe 5 years) the hydraulic pressure started forcing the Drylok off the walls along the bottom. Made it just pop off in large flakes, like cars used to do when rust got under the paint.

To really correct the problem you need to address the water on the outside. Redirecting water away from the house with gutter extensions (if you don't have gutters, there's your problem) and regrading may fix the problem. Proper grading is 1" of slope per foot for 10 feet away from the house. If not, the footer drains are probably plugged up with dirt. Might be able to pressure wash them out. More likely you will need to dig down and replace them. Waterproofing the outside of the foundation at the same time will definitely fix your problem.

Good luck.

Steve

KEJR
10-02-2011, 09:17 AM
I've heard alot of good ideas here but wanted to clarify a few things. The white fluff is on the walls, and fairly exclusively along where the outside soil level (It actually slopes up). My house is a split level type with high soil behind my house which slopes down alongside the sides of my house to level off with the driveway. So there is a rather drastic slope away from the house except for the back wall which could use some drainage or gutters as others have suggested. It is not just the back wall, as the side wall exhibits alot of this too and its soil slopes away from the foundation quite a bit.

I see some evidence of black tar looking stuff painted on just below the surface level. In some areas I see black brush strokes above ground, that is why I think it was done at one time.

There is also no "water" coming in, but I suspect it is water vapor as others have discussed. The garage does have some evidence of humidity problems but its usually at the height of summer heat/himidity (I need to seal my garage door better).

I think from your responses that I should try digging back about 6inch or 1 foot until I see the black coating and then apply another sealer on the outside for the exposed portions of concrete. Preferably something clear or gray in color to match the concrete. Any tips on products would be welcomed, but I will also talk to some concrete folks locally.

Certainly better drainage will help and I will look into that. We have alot of clay in my yard, so that isn't helping matters. The people who owned my house before didn't do crap to it in 30 years (besides plant ugly plants) so I'm playing catch-up now!

Thanks alot guys!

KEJR