Will sand around the foundation of my house help with drainage?

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It will wash away if it isn't between a sidewalk and foundation.

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I did this to my first starter home and regretted it when I had to have the basement drainage pipes snaked out when the basement flooded because sand had gotten into the drainage. I imagine you are wanting to put sand around the house for drainage purposes? I would put down a layer of plastic around the house first and maybe rocks over it, not sand. Make sure everything is slanted away from the house. If you have gutters, extend the gutter downspouts at the base several feet away from the house. Eventually, you will have to use a killer on weeds that come up in the rocks as leaves etc. decompose there. But, rocks can be a very attractive landscaping feature and you can probably go out in the country and collect them yourself, making a project out of it. It's a lot of good fresh air and exercise but don't overdo as it can wear on your joints and cause problems when you are older.