Humidity Problems in CIP Basement Wall

[mitchelon]

Here is the situation. My client has a “habitable basement” (let’s call it that for simplicity) up in the mountains of Puerto Rico. It rains significantly in this area of the country and the soil is predominantly clay. The retaining wall in question is a 6” cast in place reinforced concrete wall. The contractor did not install any type of vapor barrier material nor did he install any gravel for proper drainage. Basically, the clay is in direct contact with the wall. Needless to say, there is high humidity on the other side of the wall (paint is bulging). My recommendation is to dig, pressure wash the wall, let it dry, install a vapor barrier, install drainage pipes, and backfill with stone. The owner doesn’t want to dig because we would need to remove a big portion of his concrete driveway. What do you think? Thanks.

 

[jdonville]

mitchelon,

Sounds like you're gonna have to excavate somewhere to install a drain.

I think that you'll have to wait quite some time before the wall will dry - especially with paint on the inside surface inhibiting drainage in that direction.

Jeff

 

[brinkley]

This doesn't sound like a winning situation. It will be very difficulty to relieve the pour water pressure from behind the retaining wall without some kind of excavation.

You may have the option of repainting the interior wall with an epoxy paint that will resist the water intrusion, but the wall may need to be completely dry for that type of application.

This is a tough call to make.

 

[eric1037]

There are systems that can be installed from the inside. I believe they consist of a drainage board that is attached to the inside wall. There may also be epoxies such as Jeff suggested.

Also, you can use tieback anchors on the inside if you have wall movement.

 

[oldestguy]

If you do work outside, use no gravel or rock. Only clean coarse sand for drainage. Other stuff plugs up.