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tommac
2010-Nov-15, 02:54 AM
I am going to finish my basement which is made of concrete blocks. I currently dont have water in my basement but sometimes the concrete blocks get moist when it rains. As I will be putting flooring and some furniture and probably spending some time down there I would like to waterproof it.

There seems to be a few products on the market such as:
http://www.radonseal.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=319590&Product_Code=110&Category_Code=1

or

http://www.ugl.com/drylokMasonry/masonryWaterproofer/extreme.php

or

http://www.sanitred.com/ConcreteRepair.htm


Has anyone used any of these products in their basement or otherwise reinforced concrete blocks for waterproofing?

Do these work? I will be putting up wood walls and I am worried about mold between the cement and the wood.

peter eldergill
2010-Nov-15, 03:16 AM
You need some sort of barrier between the wood stud walls and the block walls. In Ontario, it is code to put a foam gasket between the floor and the bottom plate.

Are you planning on digging to your weeping tiles?

I did a couple of years ago. I fixed any noticeable cracks with hydrolic cement, put on a membrane roll called "blueskin" and then covered that with a dimpled plastic called platon.

We installed new weepers (with the sock), about two feet of gravel, fabric over that to keep mud out and then backfill. If you have windows, make sure you bring a weeping tile to the window well. I didn't do that and I regret it (no problems so far, I just regret not doing it)

I've not used any of the products you mention there

Here's the government of Canada website for issues involving housing. They have tons of info you might find helpful.

http://www.cmhc-schl.gc.ca/en/

Your state government should have a similar website or info

Pete

tommac
2010-Nov-15, 03:31 AM
Are you planning on digging to your weeping tiles?
What do you mean by weeping tiles? you mean the holes in the concrete block? I sort of already had this done although the people that did that work didnt do a great job with it.

I could redo that work and probably should but that is a real big job and there has not been any water in the basement since i owned the house even though it has really rained quite a bit a few times. I am mostly worried about the walls and mold.

There is one wall in particular that gets wet when it rains. I may actually redo that section because it is open anyway ( long story ).

peter eldergill
2010-Nov-15, 02:05 PM
Old weeping tiles are drainage tubes made of clay and should rest against the footing of your house underground and hook up to your city's storm sewer system. The modern ones are very long plastic tubes with holes in them to allow water to seep in and drain away.

I was under the assumption that the water issue was below ground, but it seems that it is above ground? If that's the case, I'm not sure what to tell you except you should always look up first to see if water is getting in from above somewhere. If it is leeching in through the wall itself I suppose a sealer of some sort would be appropriate but I've no experience with that.

All I've learned has been through reading books and TV (and some youtube!!)

I'll refer you to a website which has many, many people more knowledgeable than me. Not sure if you've heard of Mike Holmes. He's Canadian but I think about half the people on the website are now American. Make sure people know you're from New Jersey so they can have an idea of climate and so forth

www.mikeholmesfanforum.com

Pete

tommac
2010-Nov-15, 02:54 PM
It is below ground. I am not going to dig up the outside. I am not sure if I have these tiles ...

The water is really not a problem from a flooding standpoint. As I said it has been 3+ years and I have not had a drop of water in my basement. HOWEVER some of the walls are wet. One wall in particular. As I am finishing everything I am looking to take some extra steps from the inside of the basement to prevent mold.



Old weeping tiles are drainage tubes made of clay and should rest against the footing of your house underground and hook up to your city's storm sewer system. The modern ones are very long plastic tubes with holes in them to allow water to seep in and drain away.

I was under the assumption that the water issue was below ground, but it seems that it is above ground? If that's the case, I'm not sure what to tell you except you should always look up first to see if water is getting in from above somewhere. If it is leeching in through the wall itself I suppose a sealer of some sort would be appropriate but I've no experience with that.

All I've learned has been through reading books and TV (and some youtube!!)

I'll refer you to a website which has many, many people more knowledgeable than me. Not sure if you've heard of Mike Holmes. He's Canadian but I think about half the people on the website are now American. Make sure people know you're from New Jersey so they can have an idea of climate and so forth

www.mikeholmesfanforum.com

Pete

slang
2010-Nov-16, 12:39 AM
Do consider condensation as a possible problem for moisture problems, rather than leakage. You might spend a fortune on making your walls waterproof only to discover that you need insulation too.

NickW
2010-Nov-16, 02:44 AM
The problem in sub level walls is there will always be a problem with moisture. If you are dealing with just brick to line your foundation, you will get weeping through the brick. You can seal this to lower moisture levels, but you have to make sure you have no cracks.

If you are worried about mold between the cement and wood, you can line the interior part of the walls with Tyvek as a moisture barrier (the same stuff they use between vinyl siding and plywood on a house or apartment building). You might want to consider pressure treated lumber as well.

There are many options for this, but you have to find what will work well in your circumstance. Without more information, it makes it hard to point you in the right direction.

peter eldergill
2010-Nov-16, 03:12 AM
To me it sounds like the issue is very damp earth resting against the foundation wall which is leeching through to the inside. In the basement I doubt it would be condensation. I'm also assuming New Jersey is fairly similar to Southern Ontario (Toronto) in terms of climate.

Also, sorry to say that chances are the only way to solve the problem is to waterproof from the outside, not the inside. If you're gunna do it, do it right :) Heh...Mike Holmes

Pete

NickW
2010-Nov-16, 04:00 AM
I disagree, Peter. He shouldn't have to seal the outside. Most homes with a basement are made with the expectation that there will be moisture. The problem is we tend to use basements beyond what they are designed for. I say seal the inner walls, and use an air conditioner or de-humidifier.

tlbs101
2010-Nov-16, 04:20 PM
This link has some very useful information:
http://www.masterhandyman.com/

Search for the topic: "Basement waterproofing," for several articles and helpful hints on the subject.

tashirosgt
2010-Nov-16, 04:42 PM
He shouldn't have to seal the outside. Most homes with a basement are made with the expectation that there will be moisture.

My opinion: You may have to seal the outside. If this home is in a site where water might be coming through the block from the outside then the normal procedure for building the foundation would have been to put a barrier on the outside of the block and provide a foundation drain. If this was not done, I doubt that any amount of applying sealants or moisture barriers to the inside surface of the block will prevent future problems. If there is a condition such as a yard that slopes downhill toward a wall of the foundation, you may get some relief by re-grading the yard to direct water away from the wall.

If the moisture is coming from inside the house, such as from leaky plumbing or warm air from upstairs coming down into the basement, and condensing then those problems must be fixed.

NickW
2010-Nov-16, 06:39 PM
If this home is in a site where water might be coming through the block from the outside then the normal procedure for building the foundation would have been to put a barrier on the outside of the block and provide a foundation drain.
Normal procedure for what year?


If this was not done, I doubt that any amount of applying sealants or moisture barriers to the inside surface of the block will prevent future problems.
Depends on the amount of water. There will always be some wicking effect through the brick. Now if it is a major water issue (like a cracked foundation, or loose bricks) then you are absolutely right.


If there is a condition such as a yard that slopes downhill toward a wall of the foundation, you may get some relief by re-grading the yard to direct water away from the wall.
He could also install a french drain in that circumstance. A whole lot easier then regrading a yard, depending on the circumstance.

rommel543
2010-Nov-16, 07:10 PM
I just had this done on my house. We had the same thing, a little bit of moisture no real leaking... that is until this year. This spring we developed a small stream of water coming into the house during the snow melt, then again every time it rained this past summer. We had a company come in this fall and did some repairs. The tech that did the inspection prior to the repair told me that if you're getting moisture leaking into the house, even a little bit, you have to seal it from the outside if the ground freezes to that point. If you don't seal it the water that is currently in the wall freezes and causes the concrete to crack further making it leak more and more.

What they did to our house was similar to what Peter mentioned (http://www.bautforum.com/showthread.php/109448-Basement-waterproofing?p=1817268#post1817268); dig out the entire wall that needed to be repaired, chip out any cracks and the snap ties and fill with hydrolic cement, replace the weeping tile, then seal and cover with membrane. The one thing that was done different was the area was then filled with river stone, not gravel, with a garden fabric over top and a small layer of top soil to hold it down. The window wells are open river stone to allow drainage.
Inside the house they didn't do anything as it's sealed from the outside. I've since gone and cleaned up the crack with hydrolic cement myself for esthetic reasons.

If you're planning on doing a lot of renovation work in the basement, I would suggest getting the walls at least looked at by a couple professional companies to ensure that it's not a leakage issue. I would hate for someone to spend the money renovating then get it ruined when you could have had it repaired in the first place.

peter eldergill
2010-Nov-17, 04:17 AM
Tommac it's your house, worth many hundreds of thousands of doallars. Get at least 5 contractors to come and give you a quote/ask their opinion and don't let any of them ask for anything on site. If they are they are feeding you crap.

I agree with Rommel...water infiltration only gets worse, not better.

I'm not arguing what basements *used to* be for. We use them now in many parts of this continent for living and thus they should be watertight. The *only* way to do this is from the outside, pure and simple.

It is expensive. It is dirty. It's the only way to do it right.

I've nothing more to say on this.

North America is a huge continent. What works in Ontario is not necessarily what's best in Jersey as climate, soil conditions and building codes are all different. Ditto for any advice from this forum. Keep that in mind and the best defense is education!



Pete

tommac
2010-Nov-18, 09:49 PM
Great advice! In fact I started painting the inside with the latex paint. In the one problem area I bought this other cement stuff that is supposed to be good enough to patch pools ... I planned on using that and then covering it with the latex paint.

The guy who is doing the painting told me that it is not going to hold and that i am going to need to dig it all up and then put the stuff on the outside of the house so basically what you are suggesting.

I agree that I will need to do this work ... although a pain it is much better than gettign the basement done and furnished and then finding it flooded one day or water getting through and destroying my flooring.

I was hoping that someone would tell me not to worry about it ... but I realize that I do need to worry about it.

The other option is that I can put a sump pump there in the problem corner and pump out the water that comes through. But not sure if that is the better option. Maybe a bit easier though as I would need to dig about 6 feet deep on the outside to access this area.


Tommac it's your house, worth many hundreds of thousands of doallars. Get at least 5 contractors to come and give you a quote/ask their opinion and don't let any of them ask for anything on site. If they are they are feeding you crap.

I agree with Rommel...water infiltration only gets worse, not better.

I'm not arguing what basements *used to* be for. We use them now in many parts of this continent for living and thus they should be watertight. The *only* way to do this is from the outside, pure and simple.

It is expensive. It is dirty. It's the only way to do it right.

I've nothing more to say on this.

North America is a huge continent. What works in Ontario is not necessarily what's best in Jersey as climate, soil conditions and building codes are all different. Ditto for any advice from this forum. Keep that in mind and the best defense is education!



Pete

PetersCreek
2010-Nov-18, 10:34 PM
Before we moved in to our house, the previous owners had to address a moisture problem as a condition of sale. We live on a mountainside and subsurface water was intruding into the crawlspace. The contractor installed a French drain at the rear and one side of the house and applied a Bituthene membrane to the outside of the foundation wall, followed by rigid sheet foam insulation. It's worked pretty well so far.