Deck Depth and Vinyl Liner Float Concern

phishphan

New member
Jan 26, 2021
3
NC
Pool will be an 18x30 and as you can see from my totally not-to-scale and very poorly illustrated diagram, the yard slopes out on the back end furthest from the house. The "backside" of the pool will not be the primary lounge area so I was hoping to do minimal decking around that far end. The installer said they typically don't do less than 3 feet of deck because of drainage and concerns over vinyl liner float. They did say that in my case, given the topography, it would "probably be fine" to go with 18" of deck around the backside however it would void any warranty as relates to liner float.

So my question is - how risky is this idea? My rudimentary understanding of water properties makes me think it should seek the path of least resistance to the lower land behind That said, I'm already at the bottom of a hill, there's a creek behind the house, and our lot grade was raised up with fill dirt because of flood zone designation. BY.PNG
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
21,962
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
How much is the 18” of concrete saving you for the risk? Hardly seems worth it. It cannot cost that much more to prep 36” instead of 18” and pour concrete.

@jimmythegreek thoughts?
 

phishphan

New member
Jan 26, 2021
3
NC
Water table roughly follows the surface topography. And you have a high water table anyway. It's not a risk I would take.
The lower terrain on the right is the natural lay of the land. The house was artificially elevated during the overall subdivision grading.

How much is the 18” of concrete saving you for the risk? Hardly seems worth it. It cannot cost that much more to prep 36” instead of 18” and pour concrete.
Savings somewhere around $600 and cost is not the driving factor. Given the drop-off behind I was thinking I'd like the look of less decking as kind of a poor man's infinity pool.
 

jimmythegreek

TFP Expert
Bronze Supporter
In The Industry
Aug 10, 2017
3,158
Morris Cnty NJ
Shouldnt matter either way really. If the grade was the other way sloping to the pool amd house you could raise issue with liner float. On elevated ground liner float is greatly reduced and 18" wont make any difference