Sub drains after the fact?

[625]

I have a neighbor who has notice increased amount of moisture coming up through the concrete slab up to his hardwood floors. With the way his house was build and where it is located, that portion of his house should have sub drains under the slab, but does not. Any suggestions on what to do now? Can we trench, say 1' under the slab and 5' into the house from the edge to help move the water which I think would be less intrusive or is it even possible to have him remove the wood floors and cut the slab do a sub drain now? I don't even know if either suggestion would help. Not a groundwater problem. It is from all the crazy rain that we've been getting here in LA.

Any suggestions?

 

[Maury]

Regrade or install a perimeter drain around the outside of the foundation to direct runoff away from the house. Try this before taking the extreme measure of tearing up the slab. The outside work should be done even if he elects to install interior drains.

 

[cvg]

check the grading around the house. make sure everything slopes away from the foundation. check the gutters and downspouts and make sure those also discharge away from the house.

 

[625]

Thank you for your responses. We are in the process of improving the drainage on the outside. We are going to install pumps in two areas because there is nowhere else for the water to go. I doubt we will need sub drain once the surface drain is taken care of. thanks again.