Seal a concrete block stem wall?

[Hoops.]

I'm currently building a 32x40 into the side of a hill and am looking for some advice on sealing the block stem wall. See pic. I have already dug out to the bottom of the slab, and am planning on filling with 2-3" of washed stone,slotted socked corrugated pipe exiting on both sides, then fill to grade with washed stone. Then top with larger decorative stone. My question is the block itself. Do I apply tar and 6 mil plastic sheet to the outside? Doing research, a lot of basement waterproofing companies rip on using those products. Is the washed stone and pipe overkill already? I do plan on applying insulation to the outside before backfilling.

 

[NUTTSGT]

Scroll down to post #407.

http://www.garagejournal.com/forum/showthread.php?t=145073&page=21

If you haven't already read it, Doug has a great thread going and very informative. I'm sure if you have any questions, he would be more than happy to answer them. Keep in mind, he's a busy guy and may not get right back to you though.

 

[brownbagg]

black asphalt tar

 

[JoeFin]

black asphalt tar

and 45 lb Felt

several layers

 

[joes169]

A semi-smooth plaster coat over the back side of the block would be best, followed by one or more heavy coats of roofing/foundation sealer/tar. The stone and draintile is your best protection, along with the foam, but obviously the draintile has to exit above grade somewhere away from the garage. Also, the sock over the hose is not necessary, and more likely to plug up..........

 

[captaindiode]

They make a dimpled plastic sheet that goes against the wall and creates an air channel against the wall, Superseal is one brand. Also a product called thoroseal is easy to apply to the block with a masons brush. You can still use tar over it and then the plastic. Overkill probably, but repair in the future will be expensive. Might also consider xps foam if you plan to heat it, good idea under the slab too as a thermal break.

 

[theoldwizard1]

Scroll down to post #407.

http://www.garagejournal.com/forum/showthread.php?t=145073&page=21

They make a dimpled plastic sheet that goes against the wall and creates an air channel against the wall, Superseal is one brand. Also a product called thoroseal is easy to apply to the block with a masons brush. You can still use tar over it and then the plastic. Overkill probably, but repair in the future will be expensive. Might also consider xps foam if you plan to heat it, good idea under the slab too as a thermal break.

The dimpled plastic is called "drainboard".

There are lots of videos about basement/foundation waterproofing.

Remember, the best way to prevent water intrusion is keep it away from the wall by

1. making certain that ground level is pitched AWAY from the wall
2. providing drainage (weeping tile system) at the base of the wall

Make sure the pipe at the bottom is covered by a "sock".

 

[Hoops.]

Thanks for all the info. If I were to insulate the foundation wall with 1" or 2" foam, the membrane aka Superseal should cover the insulation as well? Or should the insulation go on the outside of the membrane?

 

[captaindiode]

I believe the insulation would go to the outside.

 

[kbs2244]

You don't need to waterproof it.
It isn't a basement wall if you are going to backfill for slab support.
Insulate if you like.
It will keep the edges of the slab warmer.

 

[joes169]

The insulation installed over plaster will do darn near the same thing as any dimpleboard, cost far less, and offer some thermal break. IMPO, the dimpleboard is a waste of money, especially for a wall of that size, and the fact that you;re putting stone and draintile at the base.

And one more time, skip the sock on the draintile, it's not worth it.......