[RE-wrenches] Strawbale wall penetration

[Bill Hoffer]

Benn

I used PVC in the my bale walls with a Junction Box on both sides of the
penetration to protect the penetration  (Outside a must!).  I used EMT for
all my other wiring, but PVC seems better for an interior to exterior
penetration where the heat conduction of the EMT may cause some damaging
condensation towards the exterior of the bales.  I used a hammer drill and
concrete bits to get through my stucco, it is tough stuff.  I used 2 "
conduit so I had to make several smaller holes and knock it out by hand.   I
did not have rebar in my bales, but heavyduty 6x6 mesh to get through, as
would be expected I never was able to hit the middle of the grid, I just had
to cut and hack saw when I hit something, pays to have a sacrificial bit to
find the metal.  I then fashioned a home made bit out of the conduit and
used that to get through the bales by hand.  That went pretty easy and will
allow you to locate the rebar without damaging an expensive bit .  Hard part
is lining up to get a good mark on the opposite side.  I used foam to fill
any gaps, replastered around the pipe and fitting and caulked really well to
seal against water on the outside.  I also located the JB on the outside of
the building in a very protected area for additional security.  Water and
straw bales do not play well together!  If anything I would favor a slight
slope downward on the outside so if there is a leak it will not follow the
pipe inward into the bales.

Hope that helps!

Bill

On Fri, Nov 19, 2010 at 11:05 AM, benn kilburn <benn at daystarsolar.ca> wrote:

>  Wrenches,
> Short of contacting the builder, i'm looking for your experiences,
> practices and "look-out's" for penetrating a strawbale exterior wall with
> conduit.
>
> For the project in question there is currently a teck cable from a wind gen
> entering the home by sharing a HRV vent opening that i want to fix (not my
> original system by the way) and i will also be adding another penetration
> for a PV array that i am relocating on the property. The original
> penetration for the PV was done properly but its not in an ideal location
> for the re-located array wiring.
>
> I'm wondering if it is as simple as using a hole saw extension to go thru
> the ~16" wall and use an LB/box on either side.  I'm sure there is some
> framework and/or rebar supporting the bales, how do you locate/avoid these
> when there are no corners to measure from?  (it is a round home)
> Any knowledge if PVC or EMT will react in anyway with the bales?  I'm
> thinking that PVC would be best....?
>
> ... i am trying to contact the builder to address this, and also to ask a
> few choice questions regarding the wiring methods (he?) used in the original
> PV system set-up.
>
> Cheers,
> benn
>
> DayStar Renewable Energy Inc.
> benn at daystarsolar.ca
> 780-906-7807
> HAVE A SUNNY DAY
>
>
>
>
> _______________________________________________
> List sponsored by Home Power magazine
>
> List Address: RE-wrenches at lists.re-wrenches.org
>
> Options & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
> List-Archive:
> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>
> List rules & etiquette:
> www.re-wrenches.org/etiquette.htm
>
> Check out participant bios:
> www.members.re-wrenches.org
>
>
>


-- 
Bill Hoffer PE
Sunergy Engineering Services PLLC
2504 Columbia Ave NW
East Wenatchee WA 98802-3941
SunEngSer at gmail.com (509)470-7762
Cell(509)679-6165
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20101119/a2d7b61d/attachment-0003.html>