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Coming to Middle Tennessee
Common Block

Our story

From sketch to block.

Common Block grows out of a block and production line we have already designed and run. Here is how it came together, and where we are now.

Track record

We've built this before.

Our team has already designed an EPS-cement block and the line that makes it, from grinding foam to casting, curing and delivery. Those blocks are in homes today.

  • Hand sketch of a block production line: mixer, placement table, curing tables and trailer
    Sketching the line
  • Hand-drawn cross-section of a block mold with notes on materials
    Designing the mold
  • Wooden mold box clamped on a casting table
    The mold
  • Open mold boxes lined up on a workbench
    Molds ready to cast
  • Close-up of ground EPS foam beads
    Ground foam beads
  • Wet foam-cement mix packed into a long wooden mold
    Casting
  • Freshly cast blocks curing on wooden racks in a tent
    Curing
  • Freshly demolded block halves showing the core shapes
    Out of the mold
  • A finished block on sawhorses, hexagonal cores visible
    A finished block
  • Blocks stacked in rows on a pallet
    Stacked and inspected
  • Tape measure checking the height of a stack of blocks
    Checking dimensions
  • Looking down the hexagonal core of a stacked block
    The core, ready for rebar
  • View through the V-shaped top of a block toward the ocean
    Course over course
  • Rows of blocks stacked outdoors with forest behind
    Ready to build
  • Finished blocks stacked on a trailer for delivery
    Out for delivery

Where it started

The Surf Block chapter.

Where
Maui, Hawaii
Feedstock
Surfboard foam offcuts
Our role
Mix, manufacturing process and first pilot plant
Pilot plant
40–50 blocks per day

In the press: Dezeen · Honolulu Magazine · Material District

On Maui, Surf Block set out to turn the foam left over from shaping surfboards into insulated concrete building blocks. The company was founded by architect David Sellers, and its blocks are made from roughly 85% recycled EPS foam.

Our team helped get it off the ground. We helped design the mix and the manufacturing process, from grinding the foam to mixing, casting, curing and delivery, and helped build the first pilot plant, which can make 40–50 blocks a day. The sketches and photos above come from that work.

It proved the idea on an island, where waste and building materials are both hard to move. Common Block takes what we learned there to Middle Tennessee, with a much bigger waste stream and a city already collecting it.

Where we are

We're not making blocks yet. Here's how we get there.

Common Block is at the starting line. The hard parts we can do ourselves are done: we know how to make this block and how to run the line that makes it. What we can't do alone is put it all in place in Nashville. That's where local support comes in.

  1. Done

    The plan and the know-how

    • Block mix and production process designed and proven on a previous ICCF line
    • Block design and dimensions set: 5 ft, hexagonal cores
    • Business plan and equipment list for a Nashville plant
  2. Now

    Building local support

    • A production space in or near Nashville
    • Clean foam supply from retailers, distributors and city collection
    • Startup funding, grants and green-building incentives
    • Builders, architects and community partners for the first projects
  3. Next

    First blocks, first walls

    • Set up the line and cast the first Nashville blocks
    • Independent fire, thermal and code testing (ASTM E119, C1363, ICC-ES)
    • Pilot walls with local builders, documented start to finish