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Community and Q&A

Electric Radiant Floors and Electromagnetic Radiation

dzndrm | Posted in General Questions on

Aside from the debate re: to use radiant floor heating or not …

I have a client who wants to install electric radiant floor heat in a small addition but is concerned about the electromagnetic radiation emitted. There will be wood in the main addition and tile in the bath.

Does anyone have experience in this? Is there a way to block any EMR?


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  1. Expert Member


    For a petty thorough airing of the issue, you may find this discussion useful:

    Here is my take from that thread:

    "As this is a site about green building, I'm wondering what you think being reasonably cautious would look like? As builders or designers we have no scientific basis or metrics of what might be considered risky, or what being reasonably cautious might entail. I'm not sure where that leaves us beyond making whatever changes worried clients may suggest. Something that in the absence of some evidence or useful guidelines I would reticent to do."

  2. Expert Member
    BILL WICHERS | | #2

    You could potentially reduce radiated fields of electric heating cables slightly by pairing them, which would mean putting the two power connections next to each other in one spot, then routing the two “sides” of the heating wire loop close to each other. You’d basically make the loop into a very long and narrow “U” shape, then route the “U” around your heating area as if both sides were actually one flat wire. This borrows from transmission line theory, which works by having current in opposite directions on each wire help to cancel the magnetic field. I’ve never tried this or made any measurements, but it’s about the simplest thing you could do. If you use the Schluter Ditra system, this would be relatively easy to do.

    As an electrical engineer though, I don’t worry about this sort of thing too much. Field strength is pretty low in general, RF causes heating of things, but that’s about it and it’s minimal at the energy densities you’re going to see here. If you want to do some basic things like I described above to try to minimize radiated fields that won’t hurt anything, but I wouldn’t make significant design changes solely for magnetic field concerns. The next step would probably be to run all your power cabling in steel conduit, and that’s going to significantly increase your wiring costs.


    1. Trevor_Lambert | | #6

      Floor heating wire already has this built in. There's only one cable, which contains the supply and return wires (twisted, usually) and ground shield. There's probably less EMF coming off one of these running at full power than there is coming from the rest of the house.

      1. charlie_sullivan | | #8

        If they are twisted, that will really reduce the external magnetic field to near zero even an inch from the cable. If DzmDrn wants to meet the clients request and go above and beyond, they can ensure the one they choose is twisted.

  3. dzndrm | | #3

    Thank you both for the very helpful info!

  4. walta100 | | #4

    Seems to me you need to tread lightly.

    While I am unaware of any valid and repeatable study showing any harm from EMR and am skeptical of the many fake studies.

    The fact is once someone has decided to believe EMR is harmful reason and logic seem infective and in fact counterproductive. The more you try to convince them it is not a problem the more you become seen as the enemy. The more you talk about this subject the more you destroy your credibility on other subjects.

    The smart move maybe to find another option rather than trying to change someone mind.


  5. Trevor_Lambert | | #5

    The fact they're even concerned about this is a huge, tinfoil flag. I would explain it's not a concern. Don't try to convince. If they don't drop it immediately, just run. Run far away and get a new client. Even if you are able to convince them, or agree to some other solution, you can bet dollars to doughnuts that they will "feel" something later on and you will get endless callbacks, trying to cure their phantom ailments.

  6. user-7513218 | | #7

    I found the folks at Warmly Yours extremely helpful in all manner of technical questions regarding their products. Ask for Laurie and she will direct you to someone that can address your concerns with specific information: (847) 550-2430

  7. user-7513218 | | #9

    Dear DznDrm , I wrote to WamrlyYours to ask about EMF and the output of their products and received a very kind reply. I paste it here for your information:
    From: Laurie Hoffman [email protected]
    Hi Fernado,

    Hope you are doing well, and thank you for your email. This is the information my boss had sent me: it’s important to realize that EMFs exist at safe levels in everyday electrical appliances. For example, a vacuum emits EMFs of 300 Milligauss (mG); a microwave emits 200 mG; and a dishwasher emits 20 mG. By comparison, WarmlyYours’s TempZone™ system emits only 1.8 mG, so it’s an ultra-low EMF level. When you think about EMFs produced by high-voltage power lines, that level can be harmful, but the EMF levels in floor-heating systems offer no cause for concern.

    Separately, I know my boss has electric floor heating throughout at his home and he is very cautious of EMF's because his son has a heart monitor implanted and high EMF levels could be dangerous for him.

    If you have any other questions just let me know.

    Thank you

  8. RashidaMuhammad | | #10

    I'm sorry for reviving a months-old thread, but maybe, someone is hunting for similar info. Though I'm not an expert on this specific issue, I'd like to share some ideas. While the electromagnetic radiation from a warm electric radiant floor is unlikely to be harmful, it’s understandable that your client may still have concerns. One potential solution to offer them is to use emf blocking fabric This fabric is designed to absorb and block electromagnetic radiation, which can provide additional peace of mind and protection. It's always important to address any concerns about safety and health when it comes to home installations.

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