Backfill and Drainage

Chuck1756

Member
Aug 4, 2020
6
Malta, NY
Wish I got onto the "French Drain for New Build" thread a few months ago. In that post Jimmythegreek talked about placing an SDR-35 drain pipe to daylight if possible with landscape fabric in a backwards Z shape. Is the 4" SDR-35 pipe supposed to be at the bottom of the collar or on top of it. Sounds like on top but will that keep water from getting under the collar?

Like this:
1598126439343.png
or does the drain pipe sit on top of the collar?

Also, I have very sandy soil and several people have told me that I am nuts spending the money for crush stone and pipe and to just backfill with what came out. I would rather hear that from someone that has experience with pools. $700 for stone, $300 for pipe while not cheap seams like good insurance. However, if complete overkill for sandy soil condition I can put that money towards a salt system.

Thanks for the help.
 

Chuck1756

Member
Aug 4, 2020
6
Malta, NY
The kit I purchased did not come with deck supports. The supplier said to stagger concrete Sono tubes as deck support. Says he can get the deck support but for the same money the sono tubes filled with concrete would be better. Is this a standard approach? If so what is the recommended spacing? I'm planning to pour a 4 ft deck around the pool and I have sandy soil. Unless the 3/4" stone and drainage pipe is over kill that is also my plan.

Thanks for the help.
 

jimmythegreek

TFP Expert
Bronze Supporter
In The Industry
Aug 10, 2017
2,931
Morris Cnty NJ
There will always be water around a pool no matter what you do unless your high and dry. The pipe is fine on top of collar. Its just to keep water low to avoid liner float and aid in liner changes. To place behind collar a form would be needed I have my overdig very tight right at 24". We get inspected here in NJ and most want the plans followed they usually spec 8" concrete collar. If you backfill with all clean stone it will never settle so you wont need the supports. I've never used them I do pavers and stone for 99% of the decks. I do use supports for anything on the deck like waterfalls etc. 4" drain pvc is fine for supports they need to be bedded in the collar during that pour amd left high. Then establish final deck height and cut them with sawzall to proper height. Deck supports on the frame is faster and easier than tubes. Larger water features or support decks should use 6" pvc or sonotubes whatever is cheaper to get