Basement Dehumidifier Advice

[N80]

Need advice on a basement dehumidifier. It is a mostly unfinished basement, 85 year old house, probably 900-1000 sq ft, concrete floors. It leaks. Water oozes in from the foundation walls but only with heavy rains. No sump at this time because there is not a single low spot to accommodate one. Only the front and sides are below grade so no seepage on the back side. Solving the problem is going to require digging all around front and sides of house and coating foundation walls. Do not have the money for that right now. After heavy rains I probably remove 20 gallons of water off the floor with the shop vac. Usually less.

So, I will make some stop gap changes to help control seepage but it is still too damp down there. My tools get a skim of rust on them, etc. However, no mold or dampness on floor joists. Anyway, I think a heavy duty dehumidifier might be in order. It will need to have a condensate pump or accommodations to fit one. I know these things can be pricey and I hear the ones from the big box stores don't last very long. So I'm looking for recommendations and any experience you guys may have with these. Thanks.

 

[k0ua]

I can't help much with the de-humidifier but I can tell you that hydraulic cement works for cracks in the basement cement walls, and that UGL works for coating the walls to prevent seepage. It really stinks to apply, but it does work.

UGL 1 gal. White Drylok Extreme Waterproofer-209100 - The Home Depot

Mortar, Cement & Concrete Mix - Concrete, Cement & Masonry -  The Home Depot

 

[mecan]

It does stink and is thick, but works

 

[KennyG]

I don't think a dehumidifier is going to solve the problem as long as you have water in leakage. Once the walls are sealed and the problem is only condensation, a combination of ventilation and dehumidification will work.

 

[4570Man]

I don't think a dehumidifier will work. You need to get the leakage stopped or install a sump pump. After that problem is fixed a dehumidifier may be needed.

 

[N80]

I agree that the dehumidifier will not work alone. But, I am going to make some stop gap changes. First, hydraulic cement over main leaks. Doubtful that it is going to work. But, there are two main leaks that account for 90% of the water. At the base of each one I am going to make a catch basin out of hydraulic cement and then put a shallow sump pump in each of those. So I should be getting most of the leaked in water pumped out. Ventilation is already adequate. (And in truth, the HVAC ductwork, both return and exit, is so old and leaky that the HVAC probably does a fair amount of air drying already.

I've looked at the UGL stuff but I assume it needs to go on the outside? This water is being pushed through very thick concrete walls 3 feet below grade so I think any coating I put on the inside is either going to get pushed off or the pressure is just going to push it somewhere else.

 

[k0ua]

I agree that the dehumidifier will not work alone. But, I am going to make some stop gap changes. First, hydraulic cement over main leaks. Doubtful that it is going to work. But, there are two main leaks that account for 90% of the water. At the base of each one I am going to make a catch basin out of hydraulic cement and then put a shallow sump pump in each of those. So I should be getting most of the leaked in water pumped out. Ventilation is already adequate. (And in truth, the HVAC ductwork, both return and exit, is so old and leaky that the HVAC probably does a fair amount of air drying already.

I've looked at the UGL stuff but I assume it needs to go on the outside? This water is being pushed through very thick concrete walls 3 feet below grade so I think any coating I put on the inside is either going to get pushed off or the pressure is just going to push it somewhere else.

Nope, the UGL goes on the inside.. It does not push off. It works. nasty stuff to apply, wear a respirator and ventilate well for a day or so. It will stop your seeps. of course cracks need hydraulic cement, then you can UGL over it. Yes the water gets thru 3 foot of concrete and is stopped dead by the coating of UGL. hard to believe, but it is true. It is not exactly a paint, it soaks in and swells up somehow.

 

[N80]

Nope, the UGL goes on the inside.. It does not push off. It works. nasty stuff to apply, wear a respirator and ventilate well for a day or so. It will stop your seeps. of course cracks need hydraulic cement, then you can UGL over it. Yes the water gets thru 3 foot of concrete and is stopped dead by the coating of UGL. hard to believe, but it is true. It is not exactly a paint, it soaks in and swells up somehow.

Wow. I will definitely be doing some more research. Most of my leaks are in a fairly small area across the front so this might be worth it.

 

[k0ua]

Wow. I will definitely be doing some more research. Most of my leaks are in a fairly small area across the front so this might be worth it.

I sealed several concrete walls in a bermed house with it that were always damp before. . The stuff really stinks by my thinking. it is thick almost like a paste. When it is fully dry, you can paint over it.

We had a leak in the basement here after road construction and all the blasting and ground shaking caused the crack. i sealed it with hydraulic cement, and UGL's over that for an area to each side.. never have seen another drop. Check it out.

 

[jmc]

Anything outside you can do to keep water away from the walls- clogged/leaking gutters, too short of downspout extensions, steeper grade away from the house, varmint tunnels....?

 

[Mysfyt]

A dehumidifier is a must have in any basement, IMHO. Just for the summer months mostly. Your basement must be kept above a certain temperature for it to be effective. For the dehumidifier in my basement, it has to be above 72* or the coils freeze up.

 

[QRTRHRS]

I cannot recall the brand that the one I had was for sure but I think it was a Kenmore. It came with a one gallon plastic tank with a molded drain fitting. I sat the unit on a concrete block with a hose from the tank to a Little Giant condensate pump. I ran the pump drain line up seven plus feet to the sewer line from my washer. Using a trap and some bushings, the condensate pump eliminated the daily tank dumping. Through ten years of running, the dehumidifier never quit but I replaced the pump once. I only had some seepage when wind driven rain hit the west side of that house but that concrete basement would rust things fast even with a parimeter drain. It was a 1600 square foot house with a full basement. I could not tell you the summer temperature. It had an oil furnace with a hotwater coil backed up with an electric hot water heater. I bypassed the furnace for hot water in warmer months. Dehumidifiers can use some power but any costs were well worth it for the difference it made.

 

[Billrog]

Check this stuff out for water proofing.
Xypex | Concrete Waterproofing using Crystalline Technology

 

[N80]

I've done some research into the Dryloc. I do not think it is going to work. These walls are rough concrete where you can actually see and feel aggregate. Maybe if I cover over the rough stuff with hydraulic cement then apply Dryloc it might work. Billrog, I'll look into the Xypex but if it paints on my walls are probably too rough.

Gutters work as typical gutters do. But, this seepage comes whether the gutters are clogged or not. Grade is flat. Not ideal but improving grade is not an option for many reasons. No critter tunnels but possibly something worse. There are 4 terra-cotta pipes on the front of the house which used to go from the gutter downspouts, all the way under basement of the house and down the hill in the back yard. This was probably a brilliant idea in 1930 and probably worked well for a few weeks. But as long as I have been around it has not worked. My gutters no longer empty into these and they have probably been filled in with roots and soil for decades and I have no idea if they contribute to the problem. The seepage occurs in places that do not line up with these pipes. My downspouts extend out into the yard now, as mentioned the grade is just about flat-level.

 

[Billrog]

George because digging wasn't an option I've dealt with 2 situations similar to yours only I don't know your soil type. One was for a customer with the same type of old ugly concrete which I had sand blasted and painted with a similar product to Xypex mixed up like a runny pancake mix. Because of the expense and mess I would not recommend it as easy or practical under most situations.
The second one was a house I owned on the west coast where it rained a lot and water ran in every time it rained and I'd have to pump it out. What I did there was pour a 3' wide concrete side walk completely around the house sloped away. In both cases over 30 yrs. later the basements are still dry. These ideas may not be of any use to you but just examples of alternative measures.
Hydraulic cement works well in chiseled out cracks and as for anything that gets pained on the exposed concrete and to be very clean for it to adhere and work as advertised. Nothing will be a quick easy fix.

 

[JimRB]

A downspout dumping water in the NW corner of the house may leak into the house on the SE side. Water makes its way where it wants to go in a rather meandering way. As saturated as my yard was after month of rain, I know there were plenty of subteranium streams.

 

[om21braz]

I sealed several concrete walls in a bermed house with it that were always damp before. . The stuff really stinks by my thinking. it is thick almost like a paste. When it is fully dry, you can paint over it.

We had a leak in the basement here after road construction and all the blasting and ground shaking caused the crack. i sealed it with hydraulic cement, and UGL's over that for an area to each side.. never have seen another drop. Check it out.

I'm going to have to take a look at this stuff myself - I've always been wary of it's ability to keep seepage out.