little help with elevation and build

[rmclain73]

Planning a new pool build and still making the decision between a vinyl and fiberglass. I have done the research between the two so I am pretty educated on the pros and cons of each. I am leaning towards the fiberglass, but there is a element to my build that may make the already higher costs even greater.

My house is located at the top of a hill, and there is quite a bit of elevation change from one end of the property to the other. The former owner leveled the grade, but for whatever reason stopped short by 11.5 feet of my property line. I currently have a fence and 4 foot wall where the grade stops. Based on the town setbacks and layout of the yard, the deep end of the pool will be right where the wall currently sits. I would like to have the entire yard be at the same grade, and have the fence pushed back to the property line.

My question is this. In order to install a fiberglass pool they need to dig out a hole to set the pool in correct? In my case there would only be enough earth to dig for half the pool. Would I first need to fill in the area where the property was stopped short, only to then dig it back out for the fiberglass pool? Can a fiberglass be installed by digging out half, then filling around the other half? Would it be easier and cheaper to put in the walls for a vinyl pool and fill around them, or would I still have to fill, then dig out the fill? Seems like a waste of fill and money if I have to go the route of filling in the yard only to then dig a good portion of it out.

The survey company suggested I maybe lower the grade some, but he was thinking more from perspective of the town and permitting. Where I live if you build a wall 4 feet and about you need it engineered and a permit. Maybe lowering the grade would help with the pool install as well, but that seems pricey as they would have to remove from a lot of square footage. Not sure what is in my best interest for terms of cost.

 

[bmoreswim]

This is where the rubber
meets the road. Any PB you would want to deal with would be able to walk you through the intricacies of all of these issues. The slope, and how the various PB's respond to it, will probably end up playing a large role in your PB selection. We selected our PB because of precisely this issue. He is a landscape guy that builds pools so he is well versed in grading issues.

My concern would be the need for the base of the pool to be on virgin soil. Then how far in the ground (below virgin soil) a FG pool would need to be. I'm assuming a vinyl pool would be fine on virgin soil but otherwise
with just backfill against it
since that's the basic way they
are built. But I am no expert for sure, except on the topic of retaining walls being expensive. To that I can attest!

 

[VinceL]

We had a fiberglass pool installed in an area of our yard with a pretty steep grade. They dug down on the downside of the slope to create a hole deep enough for the pool. There was a LOT of dirt! We have almost 2 acres of property. We had them distribute some of the dirt to other areas of the yard that needed some. But, we still have a large pile of dirt at the back of our property. We do have some plans that will use up most of it.

We also have the same regulation about taller retaining walls needing to be engineered. We have a raised spa that spills over into the pool and then a 3 foot retaining wall behind the raised spa. So, from the top of the retaining wall to the pool level is about 5 1/2 feet.

This picture gives some perspective on the slope. And, you can see our dirt pile in the background.

 

[rmclain73]

Made two phone calls today. One to was to the builder I was looking at to install the vinyl, and the second was to the manufacturer of the fiberglass.

The vinyl builder said gave two options, the first was to fill in now and wait a year or two to install the pool. The second is to put the pool in now, and wait a year or two for the decking.

The fiberglass manufacturer suggested to never put any type of pool on fill no matter how long it has been there. His suggestion was to take the yard to native soil and dig from there. Then make the pool and deck lower than the rest of the yard with steps and retaining wall down to the pool. Use the dirt from the fill removal to level out the top part of the yard.

 

[bmoreswim]

I'd have to agree. 80 tons +\- is a lot to put on fill and ask it not to settle.