Replies

1. 
   Guest_ | Jul 15, 1999 10:24pm | #13

   *
   It seems like there have been a lot of threads on wet basements, but I look through them and I do not see the answer to two questions:

   Is there a product, applied to the interior of a basement wall, that keeps the water out?

   And if there is, are there any negatives to applying it (it prevents the wall from drying, etc.).

   My customer wants her basement done, it only gets visibly wet when it rains a lot. Her neighbor had this done and it has worked well for them (so far).

   Rich Beckman

1. 
   Guest_ | Jul 02, 1999 05:13am | #1

   *Rich,Products like Thoroseal and UGL Drylok are good products ,that I would best described as dampproofing. If your customer is getting water in her basement during heavy rains do NOT finish the basement until the situation is resolved. In my opinion there is no better way then to dig out and apply a waterproofing system to the exterior of the problem area. We use Karnak plastic cement and a betonite clay board with good results. Dampproofing the interior is like putting a bandaid on an aneurysm, if it works at all it won't last long. How is the gutter system? How about the grade against the house?Is there a perimeter drain system installed now? Is the water coming in from the window wells?Check all these things first before you go slapping the Thoroseal on.Richard Max

1. 
   Guest_ | Jul 02, 1999 05:38am | #2

   *Although I am not familiar with the products Richard mentions, I agree whole heartedly with what he says about sealing the inside of wall. Here in Western WA, with much groundwater, we see a lot of leaking between the footing and foundation wall. Any real "waterproofing" needs to be done outside the foundation, not inside. - jb

1. 
   Guest_ | Jul 02, 1999 06:53am | #3

   *Yes, I tried to explain all of the above to her. I think the grade of the ground could be better, but she isn't interested in doing any of that. "The neighbor's sealed their basement from the inside, and that worked."I had thought that I had seen threads giving reasons why it was a bad idea (beyond simply not working), but now I can't find them.Rich Beckman

1. 
   DCoonrod | Jul 02, 1999 07:09am | #4

   *I am in the process of digging around a basement that I had a foundation contractor pour for me that is leaking like a spring fed cave. I had him put asphalt cement and 6 mil poly on the surface before he backfilled. We had a 8" rain in one 24 hr. period. I have contracted with an area roofing company to install a fibrous membrane that is sandwiched between two applications of a tar like substance. I'm not sure of the brand name but they have had good success with the product. I agree that any "fix" must be done on the outside. I have heard of a product called Dam-Tite for interior applications but I don't think it would stand up to the hydrostatic pressure by water deep in the soil. I have learned a valuable lesson in basement construction. Don't try to cut costs. Do it right the first time! dc

2. 
   Guest_ | Jul 02, 1999 07:14am | #5

   *Hi Jim,The betonite clay board is a product we just discovered a few years ago. It is essentially a piece of cardboard with betonite clay filling the corrugations. You apply it over the plastic cement ,( Any good brand should do, but I swear by Karnak ) tack it in place with a couple of masonry nails if needed and backfill. Sometimes in hard soils a dimple sheet is placed over it. When water hits the betonite board the cardboard eventually dissolves and the betonite clay swells up and seals the whole shebang. One waterproofing contractor I know gives a ten year guarantee against leaks on his installations. Good stuff. By the way if there are any major cracks or holes they should be plugged up with hydraulic cement first.Richard Max

3. 
   Guest_ | Jul 02, 1999 06:53pm | #6

   *I have seen the inside product used on about 10 houses. It worked on 2 of them and failded on the other 8. Not good enough odds.

4. 
   Guest_ | Jul 07, 1999 04:15am | #7

   *I dont have any technical data to back this up but it seems to me anything you put inside no matter how water proof it is has to depend on the surface bond to the wall to resist the hydrostatic pressure , if that bond failed you'd end up with a big bubble filled with water . On the outside the pressure would be pushing against the wall making whatever you used as a waterproofer seal that much tighter . Just makes sense to me . Chuck

5. 
   Guest_ | Jul 07, 1999 07:04am | #8

   *Rich , I can't tell you how many times I've been down this road! There is never an easy answer but, there is a solution. Unfortunatly it does lay at the outside, but you will need to do some home work. Is the house in a "damp" area i.e. swamp or low land etc? Is there an existing perimiter drain? Does it suffer form dampness or is there running water? Nine times out of ten the foundation does not have a perimeter drain. This should be place at the base of the footing with drainage pipe leading away from the house to a lower area or some sort of dry well. I seem to remember a recent issue of FHB with an artical on this. There are some services out there that will install a perimeter drain from the inside of the house but they can be pricey. In the Northeast I know of a company called B-dry. Perhaps there is another in your area?

6. 
   Guest_ | Jul 10, 1999 08:31pm | #9

   *.....would agree with previous posts, the exterior of the foundation is the place to start. Perimeter drain @ the footings, proper grading, downspout extentions, to direct water away from the foundation. Reduce or eliminate water around the foundation.Applying waterproofing/dampproofing to the interior may work, but you are working against hydrostatic pressure ....like trying to patch a hole in a boat from the inside ....the water coming in pushes an interior patch away where as with an exterior patch, the pressure tends to keep the patch against the boat.

7. 
   Guest_ | Jul 15, 1999 01:18pm | #10

   *Richard, may I be the first to compliment your perfect spelling of "aneurysm"! That's a tough one.

8. 
   Guest_ | Jul 15, 1999 01:23pm | #11

   *Could the water be dealt with via sump pumps(s)? I can imagine no homeowner is eager to to spend thousands and kill every bush around their house. Is the water trickling in or "sweating" in below a certain level ("it only gets visibly wet when it rains a lot")?What did the neighbor use? Is the neighbor's basement really similar?

9. 
   Guest_ | Jul 15, 1999 06:27pm | #12

   *Thank-you, one and all.Andrew,There isn't enough water for a sump pump to deal with. Homeowner says that the floor in the corner gets, maybe, 1/8" or less water. Her main concern is the general dampness afterwards. I don't know what the neighbors used, homeowner is supposed to find out. Yes, the neighbors house was built from identical plans, but that doesn't mean the grading is identical (I didn't examine the neighbors grading). Interesting though that the neighbor is downhill from my customer.Maybe a dehumidifier in the basement would be enough. I will suggest that along with a bit of work on the drainage. I am not to anxious to do the waterproofing if it isn't going to work.Rich Beckman

10. 
    Guest_ | Jul 15, 1999 10:24pm | #14

    *Thank you Andrew...I picked it up on sale at the big word store. I got it for five bucks and the guy threw in the little tail on the "y" for free.Richard Max