Semi In-ground build with raised deck

housoft said:

Been lurking here while planning the move from an intex to a more long-term solution. I've finally gathered most of my gear, started permitting, getting ready to break ground. I had some questions that are somewhat covered in various threads but I'm hoping to get some more direct advice. Thanks in advance! Build pics will be forthcoming.

General specs:
18x33ft, 54" height steel/resin hybrid, warrantied for 27" below grade.
Installing 24" below grade.

Deck to be built at 30" above grade, 1/3rd wrap around pool

Plot is level. It rains but no pooling of water.

Question 1: Sinking the pool 24", and backfill being required but not well specified like some brands, what material would be recommended to backfill? I'm currently thinking cleaned fill dirt from the excavation, tamped, sloped away from the pool, landscape fabric and river stone for the top couple inch cove sloped away from pool.

Question 2: Sinking the pool 24", what type of drainage solution should I look at? French drain intake surround to sump tank or don't worry about it if water doesnt now?

Question 3: Should I go for a foundation if a few inches of crushed rock with an inch of sand compacted for the base? This was recommended by an excavation company but I was planning to just go with undisturbed hard pack soil. Pool plans only call for standard masonry sand interior base so wondering if its just overkill or smart given temperate climate/water concerns?

Question 4: Anyone installed tube forms for deck piers in this configuration? The soil is hard but current plans have deck piers closest to the pool sitting about 12" from the dig, and those will be 24" deep as well. Any recommendations, tips, suggestions otherwise?

Thanks!

Click to expand...

Hey Housoft....

So I think I can pretty much address all 4 of your questions because I have this exact setup...

Q1. Sinking the pool 24", and backfill being required but not well specified like some brands, what material would be recommended to backfill? I'm currently thinking cleaned fill dirt from the excavation, tamped, sloped away from the pool, landscape fabric and river stone for the top couple inch cove sloped away from the pool.

A. I used the same dirt that came out of the hole I dug. But..with that said...in my area, I am lucky enough to have solid red clay dirt (Man! I Never thought in a million years...I would ever say something like that ) anyway...that red clay is hard as concrete...so when I backfilled..I built up a small slope against the pool to drain water away. This leads me to question 2...

Q2. Sinking the pool 24", what type of drainage solution should I look at? French drain intake surround to sump tank or don't worry about it if water doesn't now?

A. I installed a french drain (sort of) I laid 4" corrugated pipe all the way around the pool that dumped into a sump crock strategically located towards the end where my pool equipment pad sits. I have 6 - 4" Tee's positioned evenly around the pool with 4" corrugated pipe rising up to grade level and then installed grates at grade level. See attached pics. This drains the water from under the deck to a sump crock which will be eventually drained to a daylight drain. Daylight drain...is just a pipe buried underground that runs to a slope of the yard or to a ditch and dumps out...

Q3. Should I go for a foundation if a few inches of crushed rock with an inch of sand compacted for the base? This was recommended by an excavation company but I was planning to just go with undisturbed hard pack soil. Pool plans only call for standard masonry sand interior base so wondering if its just overkill or smart given temperate climate/water concerns?

A. Again, because I am fortunate to have solid red clay dirt, I simply laid the masonry sand on top of the clay (no more than 2" inches is recommended - I think it was 6 tons total) as my base. However, with that said...I then laid armor shield pool pad on top of that and then laid 1/2" PINK r12 insulation board (from Home Depot) on top of that. You can see the armor shield and the insulation board in the attached pics.

Q4. Anyone installed tube forms for deck piers in this configuration? The soil is hard but current plans have deck piers closest to the pool sitting about 12" from the dig, and those will be 24" deep as well. Any recommendations, tips, suggestions otherwise?

A. I struggled with this same question for weeks and very simply...Covid19 answered the question for me...Let me explain...
First, just so you know...I decided to go with Concrete Form Tubes and pour Concrete piers for my posts to sit directly on 2" above grade. Now let me tell you why covid answered it for me.... "LUMBER COSTS!" Consider this...burying 6x6 posts in the ground to below frost level (and in my case that is 36" - I live in Louisville KY) and having a deck height of 23" ...the amount of 6x6 posts would have cost me almost 3K in posts alone! but...if I pour concrete piers to two inches above grade...now all my posts are only 6" inches long...and I have 33 posts! Now of course the cost of the concrete to fill 33 36"deep holes 12" in diameter is large also. But...no where near 3K. After factoring the concrete form tubes (33 x8.00 = 264.00) + 175 bags of concrete (175x4.86 =850.50 ) + 33 Galvanized 6X6 post brackets ( 33x 17.65= 582.45) + 1 Portable Concrete Mixer you can buy at Harbor Freight for 150.00 ...the total is 1846.95. I saved 1150.00 doing concrete piers. Finally, the concrete piers that were up against the pool, I started digging with a gas powered auger (rented from Home Depot - get the kind you pull behind your truck - they are a lot more powerful and better to use) BUT -----when I got down to about 18"...I finsihed the rest of the way by hand (post hole digger). You have to be careful when digging these posts because of obvious reasons.

One final thing that I will add....

Go here The Home Depot Outdoor Projects DIY Deck, Fence, Garage and Post Frame Designer Download and install the deck designer tool on your computer. Use it to design your deck. It does a GREAT job with building a plan to build the deck. From plotting your posts to framing the deck complete with cut lengths piece by piece to a full materials list. Obviously the goal os for you to buy your lumber at Home Depot (becuase it is a Home Depot tool) BUT...you can use the material take off list and go get bids from other lumber yards Thats what I did....but in the end...in my area Home Depot was cheaper . I did buy some of my lumber at Lowes and Menards...but most of it came from Home Depot. The point is...you can use this tool to design your deck, create a blueprint to follow, and a thorough materials list.

I hope all this helps...and good luck!

-mgm