I have just had some work done to correct a drainage problem at my house. The engineers specs said to "lower the soil against the house (which I found out means raise the soil up because water is draining under the foundation slab) to expose a minimum of 2-3 inches of foundation." When they finished, they had raised and graded soil so water will drain away from the foundation, and then put grass sod in, which now brings it up to right near the top of the foundation where the brick mortar meets the foundation. Some of it is within 1/2 inch of where the house is sided instead of bricked for about 3-4 feet, and also on the east side of my house where the wall is brick. Is this ok? It is slanted down away from the foundation.

  • I don't understand why 'lower the soil' has been interpreted as 'raise the soil'; both 'raise' and 'lower' have obvious and very specific meanings. Did the engineer who wrote the specs tell you that, or did he inspect the works?
    – Bamboo
    Aug 2 '19 at 12:44
  • pictures please!
    – kevinskio
    Aug 2 '19 at 14:41

There might be two or perhaps three different principles at work here. First and most important is that surface water needs a clear escape path away from the house otherwise it ends up in the basement. So principle one is to slope the land away from the foundation. Second principle is to have the soil at the correct level with respect to the foundation independent of the grade slope. "Lower" the soil could mean that originally the soil was too high, although from your description this does not seem to have been a problem. So holding the grade angle away from the house, does it need raising or lowering with respect to the foundation. The third principle is that particularly on clay soils, when sod is laid freshly on a disturbed substrate there can be a lot of settling to take into account. What seems like a high level right now might quickly settle during a rain to what appears to be a more reasonable final level. If the final level is wrong then it needs to be redone. The trick is to get all three of these principles working together to produce the right final result.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.