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Green Building News

Hefting the CalStar Brick for Greenness, Performance

CalStar says it takes significantly less energy to make its fly ash bricks than clay bricks, but a full-fledged testing regimen specifically for fly ash bricks still has to be developed

Image Credit: CalStar Products Inc.

New construction products, especially those manufactured with new or previously ignored waste materials, no doubt make product testers’ lives interesting. Case in point is the fly ash brick developed by California-based CalStar Products.

The ecological marketing hooks for CalStar’s brick are that it is made with a material otherwise destined for a landfill – fly ash is a byproduct of coal burned in power plants – and it is produced using far less energy than that required for brick made from clay or shale. In contrast to the sustained high heat used to produce clay or shale bricks – which bake in kilns at about 2,000 degrees F for about 24 hours – far lower temperatures, near the boiling point of water, are required to make fly ash bricks, whose manufacture takes about eight hours and relies more on chemical processes than high heat.

CalStar brick will soon go into production at the company’s newly launched factory in Caledonia, Wisconsin, which will recycle fly ash from a nearby power plant operated by Wisconsin Energy Corp. Annual production is expected to be about 40 million bricks. To further reduce the factory-to-user carbon footprint, bricks from that plant will be shipped only to locations in the southeast Wisconsin region.

The standards question

The company says it has designed the bricks to meet performance standards set by ASTM International for brick strength, water absorption, and durability. An official ASTM evaluation of fly ash brick could take awhile, though. As Richard Klingner, a civil engineering professor at the University of Texas at Austin who sits on the ASTM’s panel for brick standards, told The Wall Street Journal recently, there is no specific ASTM standard yet for fly ash brick.

CalStar – whose founder, Marc Porat, also is known in the green building industry as a principal in Serious Energy and prefab specialist ZETA Communities – has gotten pushback from the Brick Industry Association, whose president, Dick Jennison, noted in the Journal story that “no one knows how the fly-ash unit will really perform.”

Other stories and accompanying reader feedback about the fly ash bricks have prompted similar comments from BIA, and CalStar responds that while standards do indeed need to be established specifically for fly ash brick, the company had little choice but to target existing standards – those for traditional brick – as it developed its product.

Other criticisms of fly ash brick have focused on potentially hazardous materials in fly ash, although the Environmental Protection Agency told the Journal that fly ash is not hazardous, and has touted the environmental and materials-performance benefits of its use in concrete and asphalt.

As its factory in Wisconsin begins production, CalStar has demonstration projects lined up to put the brick through further field tests. If it meets or surpasses performance expectations (fly ash and clay brick are comparably priced at 53 and 55 cents apiece, respectively), the big, remaining challenge of course will be to manufacture and market it more widely to spread the green-brick benefit around.


  1. bkwaas | | #1

    Calstar's Bricks are a Greenwash
    Calstar is a Greenwash.

    The company's bricks are anything but "Green", "Ecofriendly" or "Sustainable" as they claim - their product is toxic and non-sustainable.

    For example, take a look at the fly ash used for the bricks - the company plans to use ash from the Oak Creek power plant in WI. Here are the facts on the toxicity of the fly ash - EPA’s data on the toxic metals emitted by the Oak Creek power plant in its fly ash. The data was extracted from EPA’s Toxics Release Inventory.

    Oak Creek produces about 114,000 short tons of fly ash annually. The fly ash contains the following toxics (annual emissions):
    Arsenic: 6,657 pounds
    Barium: 214,501 pounds
    Chromium: 18,000 pounds
    Copper: 20,000 pounds
    Lead: 4,600 pounds
    Manganese: 13,000 pounds
    Nickel: 9,000 pounds
    Thallium: 10,000 pounds
    Vanadium: 4,750 pounds
    Zinc: 6,900 pounds

    The total amount of toxics contained in Oak Creek’s annual production of fly ash is over 300,000 pounds.

    Just ONE fly ash brick (standard size, residential, 5 lbs) contains over 3 grams of highly toxic metals.

    The toxics from just ONE fly ash brick can potentially poison 13,000 gallons of water.

    Now, imagine the toxic hazard associated by a wall of fly ash bricks.
    Imagine the toxics on your hands from handling these bricks.
    Imagine the toxics you breathe in with the dust from these bricks.
    Imagine these bricks in contact with water and the toxics leaching from the bricks.

    The leaching of these toxics from Calstar's fly ash bricks has been confirmed - the company's own results show that the bricks are unsafe and leach a whole range of highly hazardous metals.

    Calstar - the Greenwash company.

  2. bkwaas | | #2

    Analysis of Toxins Leaching from Calstar Fly Ash Bricks
    A quick analysis of the data on toxic metals leaching from Calstar’s fly ash bricks (you can find this at

    In the case of Arsenic (a listed Carcinogen) – the results show that a staggering 800 ug of Arsenic will leach from one brick in one month – or almost 10 mg of arsenic per brick per year. The arsenic from just one brick is enough to poison over 250 gallons of water. This is from Calstar’s own data.

    How about the toxic cocktail of other metals that leach from Calstar’s bricks – beryllium, cadmium, copper, lead, manganese, mercury, nickel and thallium? Over 2 grams of highly toxic metals will leach from ONE brick - poisoning over 1,000 gallons of water. Just ONE brick. All from Calstar's own data.

    How about a house faced with fly ash bricks? A standard residence in WI has about 1,500-2,000 square feet of wall face, requiring about 8,000 – 10,000 of standard facing bricks.

    So, a residence faced with fly ash bricks will have a total toxic metals content of over 20 POUNDS. These toxics leach - as confirmed by Calstar's own data, and are enough to severely poison residents and the environment - enough in fact to poison over 1 million gallons of water.

    So, a house with Calstar's fly ash bricks will in effect be a miniature fly ash landfill - leaching toxic metals and poisoning everything inside it and around it.

    There is nothing “Clean” nor “Green” about Calstar’s fly ash bricks.

  3. bkwaas | | #3

    Disinformation and Hype from Calstar Products
    Here is more disinformation from Calstar ( – concerning “Product safety”.

    Calstar claims: “Our commitment to green extends to product safety; we test our products extensively to ensure they are safe throughout their lifecycle, from manufacture to placement to use (and reuse) to end-of-life disposal”

    This is very far from the truth – Calstar has not produced enough bricks to do placement, reuse, disposal or any of the elements of lifecycle testing. Oh, and of course, they have not done an environmental footprint assessment of LCA – because, they know very well that will show what a Greenwash their product is.

    Calstar claims: “Our process for making fly ash into bricks binds the materials within a strong crystalline matrix that holds even if exposed to the intense acids found in landfills.”

    This is nonsense. Calstar’s curing process does not form any significant crystalline matrix – the borate-alkanolamine system they use has been known for decades and is known to form an amorphous matrix that degrades over time and is not effective at binding toxic metals. In fact, alkanolamines increase metal leaching, and that is why they are not used in fly ash products. And what strong acids are they talking about? The short-duration leaching tests they cite use very dilute solutions similar to rainwater which effect a very mild leach. And their own results show that toxic metals rapidly leach even under these very mild conditions.

    Calstar claims: “While hundreds of millions of tons of fly ash have been safely included in concrete buildings and infrastructures around the world for decades”.

    Nice spin. Fly ash has indeed been used extensively in concrete around the world – however, in all cases, the fly ash is safely encapsulated with portland cement and/or blast furnace slag – these are known from decades of research to react with the fly ash and effectively bind toxic metals, and the products are known to be stable and safe. This has no bearing on Calstar’s bricks. In fact, Calstar’s own data shows that metals leach from their bricks.

    Calstar claims: “CalStar Products, Inc. has undertaken extensive testing of our products to ensure the same levels of safety apply. Test results on our products from respected third-party laboratories have been reviewed and analyzed by Gradient, a respected environmental consultancy in Cambridge, Massachusetts. They find that “the presence of coal fly ash metals in newly manufactured CalStar bricks is not expected to result in any exposures of health concern”.

    More spin. Calstar has done no significant safety testing of their product, and has used a contract firm that is associated with the fly ash industry and which promotes fly ash, to certify its products. Important point here – Gradient did not do any of the tests – they were paid by Calstar to “interpret” the tests – hence the very careful wording of the safety statement. If Calstar does any meaningful testing, the toxicity of the bricks will become even more apparent – Calstar knows this all too well. The irony is that even their very mild preliminary tests show that the bricks are not safe and that metals leach out.

    Calstar – the Greenwash company.

  4. bkwaas | | #4

    Analysis of Arsenic Leaching from Calstar Fly Ash Bricks
    The SPLP data shows that the leachate contains 0.25 to 0.6 ppb of arsenic. And, the tests are conducted with 20-vols of leaching solution (relative to brick) over a period of 18 h.

    So, a standard (5 lb) brick under the same leaching conditions will equate to 11.4 to 27.4 ug of arsenic per brick per leaching period (18 h).

    So, over one month, the arsenic leaching is 456-1,094 ug of arsenic. This is enough to poison 140 to 340 gallons of water. One brick. And when you consider the cocktail of other metals that leach out, each brick is enough to poison over 1,000 gallons of water. One brick.

    The actual situation may be worse because the leaching of arsenic and other toxics from fly ash can have a significant lag phase (minutes to hours to days) characterized by a low leaching rate, after which leaching increases in a non-linear manner, and then decreases thereafter. This is because of the finite time required for infiltration, the kinetic barriers for reaction, equilibration and leaching from fly ash phases and diffusion controlled transport to the particle surface. So these results may represent the low-level kinetically-inhibited, non-equilibrium phase, and longer-term leaching may uncover the transition to a higher-level quasi-equilibrium state characterized by increased leaching of arsenic.

    The main value of the SPLP and TCLP tests is to uncover the toxic hazard.

    The fact that the tests show that toxics like arsenic leach, is an immediate and major red flag and indicates a significant health and environmental hazard.

    The actual leaching may be much worse and long-term leaching tests (years, in-place, in-the-field) must be done, and the safety of the product proven, before any decision to introduce this product

    The toxicity of fly ash bricks is a very serious issue ? not one to be so lightly Greenwashed by Calstar.

    If the bricks are truly "inert and do not leach" and are "eco-friendly" as Calstar?s CEO Michael Kane and their marketing state, then surely Calstar must be ready to back this up with a lifetime warranty that their fly ash bricks are non-toxic, not a health or environmental hazard and completely safe.

    But they will never provide such a guarantee - Calstar knows, contrary to their claims that their bricks are toxic, and they know they cannot guarantee product safety - their own tests show that the bricks leach toxics within just one day.

  5. bkwaas | | #7

    How bad coal is fly ash is?
    How bad coal is fly ash is? Here is an eye-opening quote from a news story about the DHS trying to keep the location of fly ash dumps secret - for national security purposes.

    To quote: "the Department of Homeland Security has told Sen. Barbara Boxer (D-Calif.) that her committee can't publicly disclose the location of coal ash dumps across the country."

    The full story is at:

    "The pollution is so toxic, so dangerous, that an enemy of the United States -- or a storm or some other disrupting event -- could easily cause them to spill out and lay waste to any area nearby."

    And Calstar wants to make money by selling bricks made from coal fly ash? The same stuff that is so dangerous that the DHS classifies it as a threat to national security?

  6. user-626011 | | #8

    Flyash in building products
    Dear bkwaas,

    BuildingGreen has been following the use of flyash in building products for over 15 years, and we share some of your concerns about toxins and potential leaching. We're planning an article on flyash and flyash products and would like to speak with you directly about your concerns.
    Could you drop me an e-mail so that we can set up a call?

    Thanks much,
    Brent Ehrlich, product editor
    [email protected]

  7. bkwaas | | #9

    EPA has announced a delay in
    EPA has announced a delay in pending decisions on fly ash regulation

    With recent attention on the toxic hazards of fly ash there is a good chance that the EPA will at last properly regulate fly ash as a hazardous waste under Subtitle C of the Resource Conservation and Recovery Act.

    The delay might reflect that the EPA is moving in this direction. Calstar, the American Coal Ash Association and other vested business interests have been actively lobbying the EPA to keep fly ash under Subtitle D (non-hazardous) or grant special exemption from Subtitle C - so they can keep selling their poisonous products.

  8. bkwaas | | #10

    Delusions and untruths from
    Delusions and untruths from Calstar’s CEO Michael Kane (at

    Quote from Kane: “We’re going to address the global warming issue,”

    What fanciful Nonsense! Brick production accounts for about 0.3% of total carbon dioxide emissions in the US, and under 1% of anthropogenic carbon dioxide emissions globally.

    Also, about 50-80 tons of carbon dioxide are produced for each ton of fly ash. So, the truth is that the carbon dioxie emissions associated with Calstar’s fly ash bricks are about 125 to 200 times greater than with clay bricks.

    Quote from Kane: “We’re the future.” and “The old methods of brick-making will fade away over time”

    Lets compare Calstar’s fly ash bricks with clay bricks:

    Calstar’s bricks.
    1) Made from a hazardous waste.
    2) Toxic to people and the environment.
    3) Contain and leach highly toxic metal.
    4) Very high CO2 footprint.
    5) Completely unproven – no performance data.
    6) Known to leach toxic metals.
    7) Known to have freeze-thaw problems.
    8) Known to have salt efflorescence problems.
    9) Known to have mortar bonding problems.
    10) Known batch-to-batch and within-batch variability

    Traditional bricks.
    1) Made from a renewable resource.
    2) Completely non-toxic and totally recyclable.
    3) Less than 1% of the CO2 footprint of fly ash bricks.
    4) Proven for millenia across the world.
    5) One of the most Green building materials available.
    6) Performance proven for hundreds of years.
    7) very high product consistancy.

    So, according to Calstar and Kane, a high-performance, safe, established and Green product will be replaced by a toxic, non-Green product known to have a range of performance and toxicity issues?

    A very grim future according to Calstar and Kane.

    The scam continues.

  9. bkwaas | | #11

    Calstar's CEO - Michael Kane

    Calstar's CEO - Michael Kane has jumped ship.

    In a striking and ironic refutal of Calstar's fly ash brick product, Kane has moved to Boral, the largest clay brick producer in the US.

    So much for Calstar's "Green" and "Eco-friendly" fly ash bricks. Even Calstar's own CEO did not believe Calstar's hype and greenwashing.

    Obviously Kane sees much better better prospects at Boral. Boral is a solid company with excellent products, including clay bricks, cement block and a range of building products made with fly ash. Quite the change from Calstar's greenwash operations.

    Damage control time for Calstar.

  10. bkwaas | | #12

    Finance VP leaves Calstar
    The defection of top management from Calstar continues.

    Jim Greer, the VP of Finance has left Calstar.

    This follows the departure of the Director of Research, the CEO, and the Director of Marketing.

    More evidence that Calstar is a Greenwash.

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