Pouring Styrocrete Around the Subtropical Swimming Pool

Steps

1. 1

   Step 1: Introducing Styrocrete and its properties

   I am working with Styrocrete in this episode to pour around the swimming pool in an insulating layer of concrete. Styrocrete is a concrete where the gravel is taken out and replaced by a lighter material like styrofoam. The advantages are that you can recycle styrofoam, keep costs down, and it is insulating so it holds more warmth.

   The disadvantages are that compressive strength is good, but tensile strength is lower so it breaks sooner and cannot take point loads.

   What I used

   Item	Amount	Notes
   Styrocrete	various	Insulating concrete mixture

2. 2

   Step 2: Gathering materials and making EPS beads

   The materials needed for Styrocrete are Portland cement, sand, and EPS beads. I get the EPS beads from a previous video where I made a styrofoam shredder to grind large blocks of styrofoam into small beads, making them basically free. You can check my previous video if you want to see how I made the shredder.

   What I used

   Item	Amount	Notes
   Portland cement	various	Binding agent for Styrocrete
   Sand	various	Aggregate for the mix
   EPS beads	various	Shredded from large foam blocks
   EPS shredder	1	Homemade tool to make beads

3. 3

   Step 3: Testing different Styrocrete mix ratios

   I test Styrocrete in different proportions by measuring ingredients by volume using a cup and a tablespoon. I make four different compositions with varying amounts of styrofoam and sand to see how it affects the material properties. More styrofoam gives more insulation, less sand makes the styrofoam lighter, more sand makes it heavier, and the amount of styrofoam affects the strength.

   What I used

   Item	Amount	Notes
   Cup	1	For measuring volume
   Eetlepel	1	Table spoon used for measuring proportions

4. 4

   Step 4: Analyzing test block results

   My first test uses one part cement to one part sand to four parts EPS, creating a lightweight block that almost floats and breaks very easily. A second test with even more EPS is extremely soft, movable, and hard to remove from the mold. A third test with twice as much sand is much less easy to break, though not as strong as regular concrete.

   A fifth test with more EPS breaks significantly easier than the third test.

   What I used

   Item	Amount	Notes
   Test blocks	multiple	Different mix ratio samples

5. 5

   Step 5: Choosing the 1:2:4 mix ratio for the pool

   Looking inside the blocks, high EPS density leaves high space and air bubbles with very little strength, while twice as much sand provides more internal filling and firmness at the cost of slightly lower insulation. If you need a basin in the ground that does not need high strength but good insulation, a high-EPS ratio is ideal; if it needs structural durability, more sand is better.

   For my pool, the walls are already sturdy with sandwich panels in the ground, so I choose the 1 to 2 to 4 setup of one cement, two parts sand, and four parts EPS.

   What I used

   Item	Amount	Notes
   Cement	1 part	For the selected pool mix
   Sand	2 parts	For the selected pool mix
   EPS	4 parts	For the selected pool mix

6. 6

   Step 6: Tent collapse due to bad weather

   While working on the project, bad weather strikes and my tent collapses. Heavy plates set against the stones probably blew over in the storm, and heavy wet weather created water sacks that broke the pipe and brought the flying tent down. I quickly take down the collapsed tent, clear the wreckage, and lay some beams over the area so I can walk across it.

   What I used

   Item	Amount	Notes
   Tent	1	Collapsed due to bad weather
   Beams	multiple	Laid over the area to walk across

7. 7

   Step 7: Pouring Styrocrete around the pool

   After building a new tent, I deal with typical rainy Dutch autumn weather and emergencies to push through. Over a period of about a week and a half, working between rain showers, I pour the rim around the pool with Styrocrete up to the water level. It is a messy process because rain fills the basin, requiring me to pump out water before adding new Styrocrete layers.

   What I used

   Item	Amount	Notes
   Styrocrete	various	Poured around pool rim
   Pump	1	Used to empty water from the basin between rains

8. 8

   Step 8: Finishing the Styrocrete rim and next steps

   The Styrocrete thickness varies from about 10 cm at some points to 30 cm at other points, providing a cheaper and insulating alternative to regular concrete. Once it dries and the weather clears up, I will throw sand over the harder sections to make it even. Then I can put the flexstones on the pool, cover the pool, and move on to the next step of the garden renovation: the veranda.

   What I used

   Item	Amount	Notes
   Sand	various	To level over the Styrocrete
   Flexstones	multiple	To place on the pool

9. 9

   Step 9: Takeaways

   • Styrocrete replaces gravel with EPS to provide insulation and lower costs at the expense of tensile strength.

   • Making EPS beads with a homemade shredder from foam blocks provides free material.

   • A mix ratio of 1 part cement, 2 parts sand, and 4 parts EPS offers a good balance for the pool walls.

   • Styrocrete relies on surrounding ground and pool pressure rather than tensile strength or point load resistance.

   • Bad weather can collapse work tents, requiring quick rebuilding and pumping out rainwater during pours.