Sunday, July 14, 2013

How to build a Homemade In-Ground Back Yard Pool / Spa - Germantown Philadelphia.

Our first year in the new house kept us busy, building the stone wall and clearing brush in the deep back yard. The second summer seemed hotter than ever before in Germantown, by August An old claw foot tub had been lying upside down in the tall weeds began to attract my attention. Cara and I employed it as a make shift water feature to survive the intense heat and humidity. Although we had to take turns in the tiny tub, we enjoyed it so much we decided that this was an idea that we needed to expand on and within a couple weeks we were pacing off and marking out an area in the yard. I believed at the time that this was going to be no more than a modest back yard splash pond.

Ok so its a plan, the next day we picked up a couple of shovels and started digging. We dug in the heat with great enthusiasm and while we worked we exchanged exciting ideas on how a little more work we could make it better...  so we dug some more. It seemed the more we dug the more great ideas we had! And just think... some people pay to exercise like this!

After throwing ideas (and dirt) around for several weeks we finally had carved out both a design and a 20 foot long 8 foot deep and 8 foot wide pit. We both agreed had no interest in the traditional backyard aqua blue monstrosity that most people picture when you say pool. We just want a place to cool off and float. and that it would be best if it did not look like anything more than an elegant garden reflecting pool. I said to Cara "Its going to be a sleeper" I explained to her that a "Sleeper is a street term for a car that you don't recognize as being super fast until the light changes.
She agreed, we want a sleeper.

Now we finally have a design, we decided we would build a six foot wide and six foot deep and 12 foot long "plunge chamber" with a shallow deck at one end and set it into a flagstone patio.

I sketched it up on the computer. to help with any estimates we might need to get.

Estimates for having it shot-creted were in the range of 12- 15 k!  So this really was going to have to be a "do it yourself" project for sure!

I studied many blogs and decided that for years similar projects could be and have been done with concrete block.
I decided to go with Ivany Block. Its a block that is specially designed to accept horizontal rebar as well as vertical. This block costs about 3 dollars a block but adds substantially more strength to the structure.
I calculated that about 300 blocks would cover the job and ordered a delivery from Fizzano Brothers.

So now I've got the blocks, no turning back. But before we could start building we needed a strong foundation so that would require a lot more digging and that was not going to be done this year we will have to wrap things up and wait until spring.

After a major collapse of the hole during the winter, Spring began with a lot more digging and a massive timber reinforcement project to keep the project safe as we installed the foundation and block walls. The collapse turned out to be a blessing, It required gigging out allot more space than I was initially going to and now I will have about a 26"of work space behind the wall as I construct the pool. It will also give me some additional foundation which is recommended to provide stability behind a retaining wall.

Once the retaining boards were up I began setting the drains. Three feet apart and I installed a Hydrostatic pressure valve under the drain to the right to keep the pool from floating like a ship when and if the surrounding water table rose to high.
 I set the rebar for the foundation with a grid of heavy 5 bar at  8" centers and set super heavy vertical bars before poring the foundation to insure that the walls will not separate from the floor under the pressure of back fill. To make a footing, I dug a 12" deep trench under the foundation and filled it with stone and a course of concrete block. The footing fill in as we pour the foundation and provide even more strength to the walls and foundation bed.
Here comes the concrete! I ordered a soupy mix of high strength fiber reinforced Concrete. Because of the larger footprint and the footing the total pour was 11 cubic yards! 

As the walls began to rise, we could now for the first time see what we thing were building looks like, in other words, time to make adjustments. It was decided to extend the Sun Shelf from 3 to 6 x6 feet. I believe the additional length will make for a more accommodating shallow end and create a longer more elegant esthetic.

in order to keep stacking block during the endless spring rains we built a MASH unit.
5 more yards of concrete for the sun deck, this time all mixed in the drum...
Can you believe that some people pay to get this kind of work out? 
Blocks and bars of the sun deck,  This thing is really starting to take shape.

300 blocks will hold about 4 cubic yards of concrete. If I had bad dreams last sumer of endless digging, this year it will be of mixing, luging and pouring 80 lb. buckets of mortar into 6 foot deep holes.

 I skimmed the surface with s-mix and finished up with three coats of Ramuc EP Hi-Build Epoxy. I chose Sand color to create an exotic turquoise color when filled.

 I chose a blue stone cap from Robinson Flagstone for the perimeter. Butter the back of each section and set over the bonding onto a bed of grout.
A couple of days fiddling with the plumbing and
its time to start filling the pool. 

We finished the patio by mid September and with the addition of a 266k gass heater we will be enjoying our back yard pool well into November.