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Anyone use Glass Fiber Reinforced Polymer GFRP rebar in ICF or poured concrete walls?

user-460363 | Posted in Green Products and Materials on

I’m intrigued with the possibility of using Glass rebar instead of steel. Largely because I don’t want to be surrounded by a large metal cage that could be doing various unhealthy things to us from an EMF (electro-magnetic frequencies) perspective. Also because I don’t want corroding steel in my walls.

However, I can’t get my head around the EMF implications. Do I actually WANT a metal cage around me – like a Faraday cage? Does it protect us from EMF’s? Or does it make them a bigger problem?

Any EMF experts out there?

There’s a company called Shoeck that talks about their GRFP product called “ComBAR” and how it’s better for a healthy home.

It’s several times more expensive than steel. And I don’t want to make a bad decision.

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  1. user-659915 | | #1

    Not an EMF expert but the steel in your walls will only corrode if it gets wet. That's why we have roofs. Looks to me like the extra expense of the Schoek product may be justified in particular circumstances but I doubt your home is one of them.

  2. GBA Editor
    Martin Holladay | | #2

    This question has been discussed on these pages before. You might want to read two previous Q&A threads on the issue:

    Using Fiberglass Rebar

    Building with ICFs -- will it lower the EMFs?

  3. user-460363 | | #3

    Oops. Thanks Martin. I thought I looked for an answer first, but obviously I didn't search using the right terms. My apologies.

  4. GBA Editor
    Martin Holladay | | #4

    No apology necessary. Glad to help.

  5. mjlieser | | #5

    FRP (Composite) rebar is a great way to reduce interference and EMF implications. FRP rebar is used in industrial and commercial buildings/hospitals where it is important to reduce EMF issues and to lower the cost of corrosion. Hughes Brothers and Mateen are suppliers of FRP rebar. Using it for the home is a great idea! FRP rebar is also now being used in bridge decks, concrete in sea ports where salt water attacks the steel rebar. It is a great solution.

  6. user-460363 | | #6

    Thanks Matt!

    I just got off the phone with an EMF/EMR consultant, and he pointed out something that I wasn't aware of. He said the Earth emits DC magnetic fields which the human body actually needs to be able to function. Something they discovered when they started sending people into space and they were getting sick because they had been removed from these beneficial fields.

    He thought that avoiding steel in the concrete floor would be a good thing, because the steel could interrupt or interfere with these magnetic fields.

    We didn't quite conclude on the matter of walls and ceiling (whether a Faraday cage was a good thing or not). It depends on how much my house is getting bombarded with the various waves (RF in particular). The general idea was to have the structure be as "natural" as possible, and in that sense, it would be better to have non-conductive Glass rebar instead of the conventional steel. One shouldn't really live in a Faraday cage unless it's necessary and specifically designed to address a problem. I've ordered some measuring instruments, and I'm going to investigate the fields in and around my house, and proceed from there.

  7. Pascalli2 | | #7

    Hi Zenon,

    Are you still monitoring these boards? I've stumbled across some of your comments and questions on various websites, and would like to find out what you ended up deciding on for some of the items you were looking into.


  8. user-460363 | | #8

    Hi Stephen
    Yup, I'm still here. But unfortunately, I'm also still not decided on many of the various items. We haven't built yet, due to various delays.

    I did get EMF/RF measuring equipment, and it's a very interesting learning experience. What I learned is that our house/location is quite "clean" from all that noise. Until the government allows cell companies to install wifi on every telephone pole. They won't be happy until every living organism is fully bombarded with wifi.

    One thing I learned is that "green" building doesn't necessarily mean "natural" building. And GBA is a bizarre and quizzical site. You would think they are interested in "natural" building, but mostly they are interested in maximum R values, which almost always means as much chemical-soup foam as you could possibly stuff in an assembly. There is definitely valuable information - but you need to adjust your reading for the foam-bias.

    Anyways, I don't know if they have a private-message mechanism here, and I don't want to post my contact info. So not sure how we could connect.

    I have also learned that there are contractors out there who are familiar with alternate ideas - like glass rebar, and building with an awareness about EMF, etc. They are VERY few and far between. But they do exist.

  9. GBA Editor
    Martin Holladay | | #9

    GBA invites its readers to submit articles as guest blogs. We would love to publish more information on natural building; unfortunately, we don't get as many submissions in that category as we would like to see.

    In any case, you may be interested in the following GBA articles:

    Straw-Bale Walls

    Natural Building In Nicaragua

    Nostalgia for the Hippie Building Heyday

    Low-Road Buildings Are Homeowner-Friendly

    GBA Encyclopedia: Alternative Walls

    The Natural Building Movement

    A Straw-bale Project Aims for High Performance

    How to Insulate a Slab Foundation—With Straw-Bales?

    Straw-Bale Home in the Minnesota Woods

  10. Pascalli2 | | #10

    Thanks Zenon - glad to hear you are still out there, and would be interested to find out more about what you are planning and how things are working out. Maybe you could drop me a note, if you can figure out what I mean when I write my e-mail like this: (first initial)(dot)(last name)@(

  11. Pascalli2 | | #11

    Zenon - one further thing - if you do send me an e-mail, please drop a comment here so I know, just in case it doesn't go through.

  12. user-460363 | | #12

    Stephen - I sent you a note.

  13. vrod_durability | | #13

    Schoeck is expensive as it is coming from Germany. The global leader is V-ROD, supplying a line of GFRP and CFRP reinforcing and produced in North America with faciities in Quebec, Canada and North Carolina. Please also refer to for questions and supply of V-ROD for ICF construction. Other benefits aside from being having electric/magnetic neutrality in the cases where this is of importance, is corrosion being completely removed from the equation, is 1/4 the weight of steel for handling, less fatigue or injuries for placers and reducing the weight of the componenets. Production has a much lower carbon footprint than steel and ultimately provides high performance (2-3 times tensile strength of steel) with durability and sustainability.

  14. braylonorion | | #14

    Hi Zenon,

    GFRP rebar is replacing steel fast. You can see in major civil engineering projects(highways, bridges) GFRP rebar is being used in the concrete structure. Construction companies are using them as steel alternative due to the strength and sustainability offered by these materials.
    See a great comparison of GFRP vs Steel
    Key features such as corrosion resistance, lightweight, sustainability, non-conductive to electricity and heat make them as one of the best choices over other traditional construction materials. They also address the corrosion of wastewater treatment plants, etc. So, GFRP rebar will be a good choice for commercial and other construction projects!

  15. JustJosh | | #15

    Hello Zenon and everyone else from GBA. I just stumbled upon this entry and figured I would share the 9' basement wall I am reinforcing with GFRP. The wall is 9' tall, 8" thick, and a total of 255 linear feet of wall with 34' being the longest straight wall. I've attached a picture here. GFRP certainly shines in construction projects where corrosion is an issue but given the right engineering, GFRP rebar can be used in any application.

    I don't think VROD is manufactured in the US, I think it's North Carolina facility is just a distribution hub. And Tuf-Bar is only manufactured in Canada but there are three manufacturers (to my knowledge) who are making GFRP rebar in the US. I opted for MST-BAR which is stronger in tensile strength (over 1000 MPa tensile) and and higher e-modulus (70 GPa!) which is important to make the job cost effective.

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