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Three-inch fall over length of patio---what does it mean?

Three-inch fall over length of patio---what does it mean?

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Old 10-02-19, 05:53 AM
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Three-inch fall over length of patio---what does it mean?

Hi folks. Extremely amateur question here. I'm getting ready to dig out a patio against the back of our house. A water level shows me that the yard slopes around 3 inches over the 15-foot width of the patio, running away from the house. My question: What does this mean for my digging? I know you're supposed to dig around six inches of dirt to build your patio base. Does this mean I only have to dig three inches at the far end of the patio? Or do I have to dig more at that end? Or do I just have to dig six inches around the whole thing? I can't find any explanation on the basic YouTube videos, etc. Thanks.
 
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Old 10-02-19, 06:57 AM
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Regardless of the slope if the yard you want min 1/8"per foot slope for the patio.

So, if your patio is 10' deep then you will drop approx 1 1/4" over the width.

Now, find the height where the patio will start next to the house and slope from there!

Since the yard slopes a bit more more than the patio your forms will be less in he ground at the end than next to the house.

But you are so close it's not going to be hardly noticeable!
 
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Old 10-02-19, 08:15 AM
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Thank you. Does this mean I dig down six inches and then build a slope into the excavated pit?
 
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Old 10-02-19, 08:40 AM
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If my calculation is correct then your natural slope of 3" over 15 feet is 3/16 inch per foot so I would stay with that.

The 1" per foot is a minimum and a little more is better.
So I would dig it to the 6 "
 
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Old 10-02-19, 08:42 AM
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So I just dig out six inches and build my crusher base and sand atop that? Or do I have to build a slope after I dig?
 
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Old 10-02-19, 09:04 AM
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You can go either of two ways. You can excavate your area mimicking the slope of your eventual patio. The key is you need to have enough depth for your compacted base, sand and pavers. With this method the bottom of your excavation will be sloped and so will each layer on top.

Another, less common method is to excavate the area level. Then create the slope with your base material. In this case you might have base material 6" thick at the outer edge of your patio but 8 or 10" thick near the house.

I've done both methods and each has it's benefits. If hand digging the area I'd go for option #1 because there is less digging. Be mindful that your lawn probably is uneven so it's not the best gauge for how much to dig but it's a good starting point.
 
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Old 10-02-19, 09:05 AM
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That is what I would do.

If you do that then you should have a 3 inch slope over your 15 foot patio.
 
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Old 10-02-19, 09:14 AM
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The 1" per foot is a minimum and a little more is better.
1" per foot is way too much, 1/8-1/4 is recommended.

At 1" per foot (assuming 9' deep patio) you will be 6" below grade!
 
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Old 10-02-19, 10:17 AM
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The 1" per foot is a minimum and a little more is better.

OOPS!!!
Typo on my part should be 1/8" per foot.
 
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Old 10-02-19, 11:04 AM
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Thank you everyone for your help!
 
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Old 10-02-19, 01:16 PM
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More slope is better for drainage. Many do 1/8" per foot but I find 1/4" per foot to be my minimum especially for highly textured pavers. I did the patio at my house with 1/2" per foot slope which "normal" people never notice but some engineering minded people notice the slope.
 
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Old 10-03-19, 06:36 AM
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Minimum 1/8 inch slope per foot of horizontal run/span.
Improve the drainage a little with 1/4 inch per foot.
Engineering minded people notice a slope of 1/2 inch per foot.
Better go a bit more gentle at 5/16 inch to 3/8 inch per foot
 
 

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