We're building a "healthy house" (as low VOC as possible) and thus were trying to avoid using treated sill plates as I can feel the fumes from those chemicals.

Our wood walls (hemfir) will be going directly over a recently poured concrete floor.  I'm wondering what would be the best (to prevent mold issues and breakdown of wood from concrete acid, etc) to use for a sill plate.  The options right now are:

- redwood straight over the concrete
- redwood wrapped in a vapor barrier
- hem fir wrapped in vapor barrier
- ACQ treated wood and hope it doesn't cause too many VOC problems once behind drywall
- possibly sealing any wood used as a seal plate with a water sealer from AFM

The other question is what kind of vapor barrier to use if we need to put something between wood and concrete?  We used Vaporlok by Raven Industries for below the concrete slab and have extra, but I don't know if it can be used for this application.  Most people building "healthy houses" use Tu Tuff as their barrier.

Any advice welcome.  

Thank you

Ideally you should use a flexible moisture proof material. These EDPM gaskets from Conservation Technologies should work just fine: http://www.conservationtechnology.com/building_gaskets.html
Bob

woksawi;

Code requires and impervious moisture barrier,  The vaporlok would work.   you could consider steel studs which are much healthier from an IAQ standpoint than wood

Thank you for answers. Unfortunately, with the gaskets, they use EPDM and that offgasses quite a bit so wouldn't work for same reason as why we're trying to avoid using treated wood. I'm unsure also, from reading descrip, if it's also a vapor barrier (it's an air barrier for energy efficiency but will it protect between moisture in concrete floor and wood stud?)

We looked at steel studs but are also trying to avoid creating steel cages and EMF issues...that might be way beyond the "green" thing but the house goal is to be healthy in that respect as well. Likewise, even if we could break loops, the cost difference apparently was too large.

woksawi;

if EMF is a concern to you, then you could simply nestle a 2x4 plate in a 3-5/8" 25ga. steel track.

woksawi I am curious, how do steel studs help create to EMF issues? Unless there are grounding or other electrical issues allowing objectionable current to flow through the building steel there should not be any magnetic fields from steel studs.

Bigrig -
When we started the project, we hired a baubiologist and he was the one who led us away from using any steel. He has a ton of info about it at his site:
www.createhealthyhomes.com

I'm unsure if it's because our house is all electric (I have to avoid gas, too), or if it's an issue of all the wifi that's out and about getting picked up, but that was what we were advised.

I was still up for the steel because of this issue and contractor said it's a lot more expensive, more labor. And we're already over budget (of course). Not sure if that is true about higher costs as I didn't check.

Steel track is an interesting concept - so that wouldn't require treated wood anymore by code? I wonder if steel gets a lot of condensation though (remember this is a newly poured concrete slab with lots of moisture that is all going up since vapor barrier under it).

Posted By woksawi on 11 Oct 2010 07:08 PM
Bigrig -
When we started the project, we hired a baubiologist and he was the one who led us away from using any steel. He has a ton of info about it at his site:
www.createhealthyhomes.com

I'm unsure if it's because our house is all electric (I have to avoid gas, too), or if it's an issue of all the wifi that's out and about getting picked up, but that was what we were advised.

I was still up for the steel because of this issue and contractor said it's a lot more expensive, more labor. And we're already over budget (of course). Not sure if that is true about higher costs as I didn't check.

Steel track is an interesting concept - so that wouldn't require treated wood anymore by code? I wonder if steel gets a lot of condensation though (remember this is a newly poured concrete slab with lots of moisture that is all going up since vapor barrier under it).

no steel .....next to impossible when you think about it,  re-bar, nails, screws, truss plates, light fixtures, plumbing fixtures, refrigerator, range, range hood, HVAC cabinet, duct work...... just to name a few.

In the grand scheme of things a steel track is insignificant to the steel that you cannot avoid in your home already.

The reality is steel framing provides a cleaner indoor air quality than wood. Wood can promote mold & mildew growth, attract insects.

At some point you need to pick your poison, there is not any building material that is 100% flawless. Ithink your Bau Biologist is a little paranoid.

To clarify - he wasn't saying no steel at all of course, he said no steel framing unless it's grounded well.

With the steel track - my understanding was that you'd still need treated wood since the track can have condensation from the curing concrete.  Maybe that is incorrect.

Posted By woksawi on 11 Oct 2010 07:08 PM
Bigrig -
When we started the project, we hired a baubiologist and he was the one who led us away from using any steel. He has a ton of info about it at his site:
www.createhealthyhomes.com

I'm unsure if it's because our house is all electric (I have to avoid gas, too), or if it's an issue of all the wifi that's out and about getting picked up, but that was what we were advised.

I was still up for the steel because of this issue and contractor said it's a lot more expensive, more labor. And we're already over budget (of course). Not sure if that is true about higher costs as I didn't check.

Steel track is an interesting concept - so that wouldn't require treated wood anymore by code? I wonder if steel gets a lot of condensation though (remember this is a newly poured concrete slab with lots of moisture that is all going up since vapor barrier under it).

All electric means the radiated very low frequency EMF due to heating equipment currents will be 10x higher than without.

Steel is used as a shielding element for EMFs across the spectrum.

Aluminized polyester type radiant barrier is an effective broad-spectrum EMF shield.

Worrying about EMF related to use of steel studs in the structure is totally out to lunch.  In a static field/low frequency environment the effect of the presence of the steel may distort the field, but does not focus it or change it's intensity.   Unless you're living at a power substation you'll get more  exposure to low frequency fields from your doorbell transformer, which is still orders of magnitude  lower that what you're getting from the power supplies for your computer & computer screen. (If you have an old-school CRT display its even worse!) Steel structural elements are more likely to be protective than increasing your exposure (but more likely to be neutral.)

And the steel is a heluva lot less relevant, than say, how your building  or appliances are wired, and separation between the line & neutral, whether the wires are twisted vs. parallel, etc. the extent of capacitive coupling to earth grounds creating secondary return paths, etc.

Methinks the baubiology take on EMF is BS designed to fleece the anxious.  The range of recommendations for mitigating EMF exposure run from plausible to ridiculous, but misses some big gaps in the physics in between.  If you really need to limit EMF exposure (and I doubt you do), you'd be better off living in an all steel building with the power routed in steel conduit.

Can someone send a link where I can view what a steel track system looks like?

How are the tracks attached to the concrete floor? (It's only 2 inches of concrete with radiant tubes in it - concerns about puncturing tubes).

And does the framing go right into the steel track then? Can wood framing be used in a steel track?

I probably misrepresented what the guy said -- I'll get more info so I can clarify, but in terms of creating a cage of steel with the framing, there was an issue that others with wifi and electrical sensitivities seem to follow so I'll get the info correct and post it. And yes, there are very specific electrical specifications as well.

steel studs/track

Posted By woksawi on 12 Oct 2010 06:07 PM
Can someone send a link where I can view what a steel track system looks like?

How are the tracks attached to the concrete floor? (It's only 2 inches of concrete with radiant tubes in it - concerns about puncturing tubes).

And does the framing go right into the steel track then? Can wood framing be used in a steel track?

I probably misrepresented what the guy said -- I'll get more info so I can clarify, but in terms of creating a cage of steel with the framing, there was an issue that others with wifi and electrical sensitivities seem to follow so I'll get the info correct and post it. And yes, there are very specific electrical specifications as well.

Steel framing does not present a relevant resonant length for blocking or interfering with wi-fi.  Wi-fi is all low power microwave, with quarter-wavelengths well under a foot, and would require a mesh of under a quarter-wave to have even the slightest shielding effect. ELF has quarter wave lengths measured in thousands of miles, which also renders the length of a steel stud mostly irrelevant since it would all be near-field effects,  but a full aluminum sheet like a foil radiant barrier would have a modest shielding effect on ELF ( but not as much as a thicker layer of aluminum), yet a very significant effect on wi-fi.  Metal siding roofing or lift-slab flooring etc. can have relevant effects across a broad spectrum as well.

"electrical sensitivities" at the field strengths normally found in homes is complete BS.  Even when strong enough to have laboratory-measurable biological effects there is no proximate correlation with human-sensible symptoms.  It takes a VERY strong field to produce measurable ill-effects even over extended time, and orders of magnitude higher than that to be immediately felt.   We are all of the same biology- unlike the situation with chemical sensitivity  (involving a lot of individual-specific immune & other system differences), there there is no credible basis for the notion that some humans are more/less sensitive to EMF than others.

Full disclosure: I have made a living in the past (and sometimes even now) controlling electrical & magnetic radiation across a broad spectrum in both electronic systems and sometimes buildings.  Trust me when I tell you that the routing of power line neutrals & grounding have a much much greater impact on local field strengths for very low frequency EMF than any building material.  The resonant length of a steel stud is in 10s of megahertz, a frequency component you might find radiating off computer power supplies, fluorescent ballasts, and LED or CFL bulbs, but not anything commonly used for communications within a home.  If you want to worry about it, consider that you'll have 100s (even 1000s) times greater exposure running a laptop or notebook computer sitting on your lap than anything you might pick up off radio frequency ringing of the metal studs (which would be less than the exposure you're getting from the commercial radio or TV transmitter 20 miles away.)

To the guy who insinuated that all my sensitivities are insane (I think his post is about to be deleted but still...)

You're sadly ignorant.

I suffered massive toxic injury 10 years ago - literally was poisoned and it partially wiped  out my detoxification system and caused injury on many physical levels.  Then while trying to recover I moved into a toxic mold house and that was the final straw.  I now have to take IVs twice a week and a nebulizer twice a day of a medication that my body no longer even makes --- this medication helps me process toxins because my body no longer processes toxins on it's own on any level.  I also have to use oxygen.  And I have to avoid exposures.  And I'm a mother.  And, yup, I'm completely sane.  I would say that you might want to raise your awareness that not everyone is healthy like you and you should be more compassionate.

We're building this house for my health.  And yes, because you're one of those people, there is very hard scientific evidence that what I live with now is real, and no it is not trauma induced.  In fact, there are kids born with impaired detox systems who also are acutely sensitive -- but they did not have emotional trauma for ignorant others to try to blame their condition on.  The hardest part is having to defend myself.

Whilte I might be confused about the steel framing issues, at the least I want to clarify this:

electrical hypersensitivity references

http://bcn.boulder.co.us/health/rmeha/rmehemfs.htm#eref

http://www.aehf.com/articles/em_sensitive.html

http://www.citlink.net/~bhima/emf.htm

Posted By woksawi on 13 Oct 2010 01:45 PM
You're sadly ignorant.

I suffered massive toxic injury when I was in NYC during 9/11 - literally was poisoned and it partially wiped  out my detoxification system and caused injury on many physical levels.  Then while trying to recover I moved into a toxic mold house and that was the final straw.  I now have to take IVs twice a week and a nebulizer twice a day of a medication that my body no longer even makes --- this medication helps me process toxins because my body no longer processes toxins on it's own on any level.  I also have to use oxygen.  And I have to avoid exposures.  And I'm a mother.  And, yup, I'm completely sane.  I would say that you might want to raise your awareness that not everyone is healthy like you and you should be more compassionate.

We're building this house for my health.  And yes, because you're one of those people, there is very hard scientific evidence that what I live with now is real, and no it is not trauma induced.  In fact, there are kids born with impaired detox systems who also are acutely sensitive -- but they did not have emotional trauma for ignorant others to try to blame their condition on.  The hardest part is having to defend myself.

Where's the toxic effects of the EMF in all of this?

(I freely acknowledge that chemical sensitivity issues are quite real & immediate.)

I'm just saying that at the levels seen in most houses there are no sensitivites to EMF that would cause immediate or even short term symptoms, even if there are sometimes levels where long-term biological effect might be measurable.  It takes a heluva EMF dose to cause immediate symptoms.  It takes orders of magnitude less to cause damage, but that damage typically takes years/decades to exhibit itself.

Back to the subject at hand, If you can find old growth redwood, it was a common sillplate material, long before PT lumber came out. Other possibilitys include white oak, old growth cypress.

Dont use Mansenea, although it is very rot resistant and hard, It has known chemical sensitiviy issues.

To me, it seems like the single biggest thing you need is a very high exchange rate with outside air, going through a Hepa filtration system.

Cheers,
Eric

Posted By woksawi on 13 Oct 2010 01:53 PM
Whilte I might be confused about the steel framing issues, at the least I want to clarify this:

electrical hypersensitivity references

http://bcn.boulder.co.us/health/rmeha/rmehemfs.htm#eref

http://www.aehf.com/articles/em_sensitive.html

http://www.citlink.net/~bhima/emf.htm

Half the links pointed to in the bcn.boulder point to either generic front pages or broken links.  Of the links that work, yes, the NIOSH levels are acknowledged health risks (but not of immediate symptomology), but are levels many many time what you would experience in a home environment.  The World health organization link on that page (that DID work) states:

"A number of studies have been conducted where EHS individuals were exposed to EMF similar to those that they attributed to the cause of their symptoms. The aim was to elicit symptoms under controlled laboratory conditions.

The majority of studies indicate that EHS individuals cannot detect EMF exposure any more accurately than non-EHS individuals. Well controlled and conducted double-blind studies have shown that symptoms were not correlated with EMF exposure."

I'm not saying that those people don't have symptoms, but am suggesting that ascribing those symptoms to proximate EMF exposure isn't likely to be correct. (And the body of evidence in the scientific literature surveyed by the WHO seems to support that thesis.)   Spending actual money to mitgate something that almost certainly isn't the issue would be a waste.

The aehf.com article has such ridiculously low numbers, primarily single-blind that it's not exactly great science, but OK, you'd want to do a bigger & better test to actuall measure whether it was statistical noise, not EMF noise driving the result.  The fact that the "sensitive" subjects in the very small double-blind portion were also reacting to "blanks" begs for a deeper explanation. The fact that they were using square waves means that the frequency component has odd-harmonics extending to an unspecified upper bound in frequency too, making it difficult to assess what part of the spectrum is most relevant, if the reaction is real.

The citlink.net link was devoid of anything remotely like science, but in the Q &  A bit, section "4 EMF Control for Homes" they correctly point out that higher level exposures to low frequency EMF are likely to be related to the power/neutral wiring errors in the building. (Which is exactly what I was talking about in prior posts.)  These issues are largely unaffected by choice of building materials, however.  If you care about this (and I believe you DO), use only twisted power cabling (no romex), run it in metal conduit, and make sure that your electricians don't create loops in the phases or neutrals, and there is but one hard connection between the neutral & earth-ground.

Posted By woksawi on 13 Oct 2010 01:45 PM
You're sadly ignorant.

I suffered massive toxic injury when I was in NYC during 9/11 - literally was poisoned and it partially wiped  out my detoxification system and caused injury on many physical levels.  Then while trying to recover I moved into a toxic mold house and that was the final straw.  I now have to take IVs twice a week and a nebulizer twice a day of a medication that my body no longer even makes --- this medication helps me process toxins because my body no longer processes toxins on it's own on any level.  I also have to use oxygen.  And I have to avoid exposures.  And I'm a mother.  And, yup, I'm completely sane.  I would say that you might want to raise your awareness that not everyone is healthy like you and you should be more compassionate.

We're building this house for my health.  And yes, because you're one of those people, there is very hard scientific evidence that what I live with now is real, and no it is not trauma induced.  In fact, there are kids born with impaired detox systems who also are acutely sensitive -- but they did not have emotional trauma for ignorant others to try to blame their condition on.  The hardest part is having to defend myself.

In my defense, the sum of your posts and your symptoms was quite "over the top" with absolutely no explanation of the reasons.  I used to work for a health insurance company & took calls from people upset because we didn't want to pay their claims when they went to the dr. to get tested for everything under the sun.  If what you're saying is true, you're definitely the exception.  You have to accept that people are going to be skeptical.

I've been posting on this board for some time.  I'm not a troll & I'm not looking to get a rise out of anyone.  I do think that you're fighting an uphill battle if you're going to try to build a house with no chemicals, no steel, etc.  Short of going into the woods, chopping down trees, & building yourself a log cabin, I don't see how you can do it.  I agree with, Eric, I think - that your best bet is going to be to focus on indoor air quality - HRV/ERV, HEPA filters, etc.

We built a house this year & the "new house smell" was pretty strong for a while.  My wife is pregnant, so it really got to her.  Having the HRV running on high all the time cleared it out fairly quickly & made an enormous difference.

http://international-emf-alliance.org/index.php/media-info/videos

low levels absolutely impact people...