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quentin Posted: Aug 16, 2008 01:38 PM	Leaking basement My neighbor has a remodeling job for a basement he is going to be doing as his business as a handyman and one place he just looked at has a problem with seeping in the basement. I know if you spray the outside before grading closed cell will seal it but what about spraying the inside of the walls instead? Would a couple of inches of closed cell on the cement block walls seal it or would the water push the foam and cause it to break away and then leak again?
mason Posted: Aug 16, 2008 07:10 PM	Closed cell SPF will seal the leaks to a point. If the hyrostatic pressure is too high, the water could enter the foam. To be safe, seal the cracks with a good urethane sealant specifically designed for that use and then foam the wall. PS, my basement wall had some seepage but my water table is far below my basement, so I just foamed the wall and it has been no problem.
quentin Posted: Aug 16, 2008 08:21 PM	Thanks! I will have to check since the water table here depends a lot on where the house is. If it looks like it is minor, then I may talk to him about doing it. He gave me an interesting proposal since I am having a hell of a time getting a business loan with the present economic conditions and my divorce. Something along the lines of an interest free loan in return for free work.
Jim Coler Posted: Aug 16, 2008 09:40 PM	Don't overlook the obvious but commonly overlooked gutters and downspout issues. If the water only comes in during and after a heavy rain, then it may be an issue with water and pervious soil management. If the gutters are not properly sized, the downspouts are less than 10' out and not downhill, then fix these issues first and then you can insulate and seal the basement. It's easier to show the effect of the rainwater drainage before foam goes on and education is half the battle. Also, make sure the basement wall is clean and free of dust/debri. With a stone basement wall, you may want to repoint it before foaming.
mason Posted: Aug 18, 2008 07:57 AM	Riverrocks, Thanks for the added info, very helpful. Just remember, closed cell SPF is a dampproofing material not a waterproofing material. It has very good water resistance if there is not a strong hydrostatic pressure. To give an example, a 2 lb SPF in 2 foot of water will absorb about 1/2 to 1 inch of water in a couple of months. (I used to spray foam floating docks for folks in South Padre Island, and one guy did not want to put a water proof coating over the foam. He brought the dock up after the summer season and let it dry out and put it back in. I don't recommend it, but it did show me how much water would go into the foam in a specific period of time)
Circle-D Posted: Aug 19, 2008 09:55 PM	Mason, Wouldn't there be a concern about sealing the inside of the basement? The water is still going to get into the foundation and stop at the foam on the inside. Wouldn't the foam will hold the heat in the basement, thereby allowing the water in the foundation to freeze and cause structural damage?
andy buff Posted: Aug 20, 2008 07:42 PM	mason,what did you use for closed cell foam on the docks,2 or 3 lb? and what did you paint it with.i've got a duck blind to do.also if there was mold on the bottem of a roof deck in a small area would the foam be hot enough to kill and encapsulate it...thanks
mason Posted: Aug 24, 2008 09:59 AM	The specific dock that I referred was not coated, that is why the foam got water saturated 1 inch within the surface. I used a 2.5 lb density foam. Normally I would use a low perm rated coating such as a polyurethane or a chlorinated rubber coating.
mason Posted: Aug 24, 2008 10:02 AM	The water should not freeze below grade. The ground is a pretty good insulation by itself. Unless you are in a permafrost condition such as the artic the ground should not freeze below a few inches. The water is going to be in the foundation no matter what you do unless you dig out the whole foundation, install a waterproofing coating to the concrete and then insulate it with foam. But, I thought this option was discarded due to expense. Regrading the property would help as well.

Author

Comments

quentin

Posted: Aug 16, 2008 01:38 PM

Leaking basement

My neighbor has a remodeling job for a basement he is going to be doing as his business as a handyman and one place he just looked at has a problem with seeping in the basement. I know if you spray the outside before grading closed cell will seal it but what about spraying the inside of the walls instead? Would a couple of inches of closed cell on the cement block walls seal it or would the water push the foam and cause it to break away and then leak again?

mason

Posted: Aug 16, 2008 07:10 PM

Closed cell SPF will seal the leaks to a point. If the hyrostatic pressure is too high, the water could enter the foam.

To be safe, seal the cracks with a good urethane sealant specifically designed for that use and then foam the wall.

PS, my basement wall had some seepage but my water table is far below my basement, so I just foamed the wall and it has been no problem.

quentin

Posted: Aug 16, 2008 08:21 PM

Thanks! I will have to check since the water table here depends a lot on where the house is. If it looks like it is minor, then I may talk to him about doing it. He gave me an interesting proposal since I am having a hell of a time getting a business loan with the present economic conditions and my divorce. Something along the lines of an interest free loan in return for free work.

Jim Coler

Posted: Aug 16, 2008 09:40 PM

Don't overlook the obvious but commonly overlooked gutters and downspout issues. If the water only comes in during and after a heavy rain, then it may be an issue with water and pervious soil management. If the gutters are not properly sized, the downspouts are less than 10' out and not downhill, then fix these issues first and then you can insulate and seal the basement. It's easier to show the effect of the rainwater drainage before foam goes on and education is half the battle.

Also, make sure the basement wall is clean and free of dust/debri. With a stone basement wall, you may want to repoint it before foaming.

mason

Posted: Aug 18, 2008 07:57 AM

Riverrocks,

Thanks for the added info, very helpful. Just remember, closed cell SPF is a dampproofing material not a waterproofing material. It has very good water resistance if there is not a strong hydrostatic pressure. To give an example, a 2 lb SPF in 2 foot of water will absorb about 1/2 to 1 inch of water in a couple of months. (I used to spray foam floating docks for folks in South Padre Island, and one guy did not want to put a water proof coating over the foam. He brought the dock up after the summer season and let it dry out and put it back in. I don't recommend it, but it did show me how much water would go into the foam in a specific period of time)

Circle-D

Posted: Aug 19, 2008 09:55 PM

Mason,
Wouldn't there be a concern about sealing the inside of the basement? The water is still going to get into the foundation and stop at the foam on the inside. Wouldn't the foam will hold the heat in the basement, thereby allowing the water in the foundation to freeze and cause structural damage?

andy buff

Posted: Aug 20, 2008 07:42 PM

mason,what did you use for closed cell foam on the docks,2 or 3 lb? and what did you paint it with.i've got a duck blind to do.also if there was mold on the bottem of a roof deck in a small area would the foam be hot enough to kill and encapsulate it...thanks

mason

Posted: Aug 24, 2008 09:59 AM

The specific dock that I referred was not coated, that is why the foam got water saturated 1 inch within the surface. I used a 2.5 lb density foam. Normally I would use a low perm rated coating such as a polyurethane or a chlorinated rubber coating.

mason

Posted: Aug 24, 2008 10:02 AM

The water should not freeze below grade. The ground is a pretty good insulation by itself. Unless you are in a permafrost condition such as the artic the ground should not freeze below a few inches.

The water is going to be in the foundation no matter what you do unless you dig out the whole foundation, install a waterproofing coating to the concrete and then insulate it with foam. But, I thought this option was discarded due to expense.

Regrading the property would help as well.

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