What is EFC surfboard foam?

Posted on January 23, 2014 by Pete Hardie

EFC Surfboard Foam

The short answer:

Extruded Flex Core is a new type of extruded polystyrene foam. EFC is an alternative to the "standard" PU (Polyurethane) and to EPS (expanded polystyrene foam).

A Chunk of EFC Surfboard Foam

Examing a chunk of EFC foam in the REAL boardloft

Need to know:

EFC is the result of a partnership between Hydroflex Surfboards and Marko Foam. To find out more, we caught up with Hydroflex's main man Rich Ciesco.

How is EFC different to EPS?

Rich: EFC (Extruded Flex Core) is an Extruded Polystyrene, which means it's extruded in square chunks out of a machine in long blocks. The cell structure is a closed cell foam, which means it won't take on air or water. EPS (Expanded Polystyrene) is made by putting polystyrene beads into a mold and adding steam to them to make them expand. These beads and the bonding between the beads is not air tight or water tight.

Is there any price difference for EFC foam boards vs EPS or PU?

Rich: The EFC foam is slightly more expensive and the result is a more durable board against denting and also one that is watertight if you ding it. This makes it an ideal foam to use for a travel board.

How long has EFC been around for / what has the feedback been from surfers riding these boards?

Rich: We have been developing the foam for about a year now and all of the testing has received really positive feedback. The foam is very consistent and durable, making it a great choice for your go to shape.


EFC foam with Hydroflex's 3D vacuum-bagged glassing addresses 2 main concerns of every surfer out there: deck-denting durability and water-tightness in the event of a ding.

I want one for my next trip:

Hydroflex EFC foam is now available in your shape for all custom orders through REAL and is available with or without a stringer. For more info contact us at realpro@realwatersports.com.

EFC Surfboard Foam - Roberts Black Punt

Roberts Black Punt in EFC Construction By Hydroflex

3 Response(s) to What is EFC surfboard foam?

  • vince castaneda says:

    is sean Madison from VON SOL associated with HYDROFLEX ? If so i would like to get an EFC board with sean madison's VON SOL " SHADOW "

    Posted on February 28, 2014 at 12:24 pm

  • Pete Hardie says:

    Thanks for your comment Clark - glad you're so stoked on your board!

    Posted on January 24, 2014 at 5:18 pm

  • Clark says:

    I have been riding HydroFlex for years. This is the foam Bufo and the boys were using in Europe. When they opened up in Oceanside CA, they had no access. Two of the best boards I have ever ridden were EFC. I was delivered a new Bufo a few months ago with EFC, love it. Have the guys at Real cut a custom for you. It will change your life.

    Posted on January 23, 2014 at 4:49 pm

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