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Gravel under the deck?

Our home got a tall deck at back of the house, the backyard has some slope. During rain, it became muddy on the ground (under the deck), also due to the drainage pipe was not smooth (might be blocked/narrowed somewhere under ground), big rain will cause water to build up underneath the deck around the foundation..
I ordered 8 yards of 1 inch gravel and put them under the deck, the deck size is about 370 sq feet. I think I ordered a lot more than what actually needed, the thickness is roughly above 4 inches and even about 7 inches at one side.
To stop the water to sink into the ground, I put a layer of plastic underneath the gravels.

Now someone told me this is a wrong way, and this will cause damage to the foundation, since water will build up there under the gravels and will not be dried by sun.

I want to know whether what I did was really wrong or not; if wrong, what should I do now?

Thank you very much for your answer.

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Super Green Thumb
Posts: 25303
Joined: Sun Feb 15, 2009 11:04 pm
Location: TN/GA 7b

Re: Gravel under the deck?

Yes. I'm no expert, but I think wrong. You wanted the water to drain away, either into the ground or down the slope away from the house. If your ground does not slope away from the house, but slopes towards it, I think you just HAVE to re-do everything and have the ground re-graded. Otherwise your house will be at serious risk.

Assuming the slope is away from the house, I think you could get away with pushing a sharp pointed stick or rod down through the gravel and the plastic, into the soil making drainage holes. You would have to make a whole bunch of them, but it is still probably easier that trying to remove all the gravel to be able to remove the plastic.
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