The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Page 1 of 2 1 2 >
Topic Options
Rate This Topic
#121636 - 08/04/05 08:53 PM Foam in Boxes
Webmaster Offline

Administrator
Member

Registered: 10/07/00
Posts: 3142
Loc: NY, USA
(submitted by Joe Tedesco)
 Quote:
Hey Joe,


I thought you might like this picture of somebody's "clever" weatherstripping of a receptical. It was found in an apartment renovated a few years ago under a permit! Not too sure how this got slipped past inspection, but all of the recepticals on the outer walls are just like this.

I took this picture myself and you may use it for anything you want.

-Joey

Top
Tools for Electricians:
#121637 - 08/05/05 11:21 AM Re: Foam in Boxes
Radar Offline
Member

Registered: 04/30/04
Posts: 349
Loc: Los Angeles, CA
Kinda wrecks the old box fill calculations, don't it.
_________________________
There are 10 types of people. Those who know binary, and those who don't.

Top
#121638 - 08/05/05 01:03 PM Re: Foam in Boxes
alan bergold Offline
Member

Registered: 11/20/01
Posts: 51
Loc: east meadow ny
how do we calculate foam into box fill calculations?
_________________________
JBIELECTRIC EAST MEADOW NY

Top
#121639 - 08/05/05 03:21 PM Re: Foam in Boxes
electure Offline

Member

Registered: 12/24/00
Posts: 4226
Loc: Fullerton, CA USA
Easy

4 x 4 x 1-1/2 Box = 21 cu in per 314.16 (A)

3 #12 conductor @ 2.25 cu in each = 6.75 cu in.

1 device @ 2 x 2.25 cu in = 4.5 cu in

1 Foam job @ 9.75 cu in

Perfect fit

Top
#121640 - 08/05/05 04:32 PM Re: Foam in Boxes
sierra electrician Offline
Member

Registered: 02/12/05
Posts: 220
Loc: North Fork, CA USA
4 x 4 x 1-1/2 Box = 21 cu in per 314.16 (A)

3 #12 conductor @ 2.25 cu in each = 6.75 cu in.

1 device @ 2 x 2.25 cu in = 4.5 cu in

1 Foam job @ 9.75 cu in
_________________________________________________

= 0.00 cu in + Fire Hazzard x (10)2 = Complete Violation & Installer must be shot.

Top
#121641 - 08/05/05 07:28 PM Re: Foam in Boxes
mxslick Offline
Member

Registered: 10/24/04
Posts: 785
Loc: Atomic City, ID USA
But it keeps the recept. and terminals at a constant toasty temperature....what's the problem?

And it eliminates that annoying loose device wiggle, too.

Constantly amazes me how dumb some people can be...
_________________________
Stupid should be painful.

Top
#121642 - 08/07/05 04:02 AM Re: Foam in Boxes
Trumpy Offline

Member

Registered: 07/05/02
Posts: 8540
Loc: SI,New Zealand
Boy!,
I bet that was hard to get out!.
What's more concerning, is the stuff that Expanding foam is made out of.
_________________________
Let's face it, these days if you're not young, you're old - Red Green grin

Top
#121643 - 08/07/05 06:19 AM Re: Foam in Boxes
techie Offline
Member

Registered: 05/17/05
Posts: 240
Loc: palo alto, ca usa
I see what looking like pink fiberglass insulation the the lower corner of the box.. is there actually a box there? or just a mud ring?

Top
#121644 - 08/07/05 02:45 PM Re: Foam in Boxes
Theelectrikid Offline
Member

Registered: 04/30/04
Posts: 854
Loc: Levittown, PA
"I see what looking like pink fiberglass insulation the the lower corner of the box.. is there actually a box there? or just a mud ring?"

Is there even a box here?

[This message has been edited by Theelectrikid (edited 08-07-2005).]
_________________________
Is there anyone on board who knows how to fly a plane?

Top
#121645 - 08/07/05 05:58 PM Re: Foam in Boxes
jdadamo Offline
Member

Registered: 11/10/04
Posts: 37
Loc: Calgary, AB, Canada
Yes there is a box there. You will notice that the insulation is actually on the outside of the mudring. What I'm wondering now is where the vapor barrier is. I wonder if somebody stuffed that in there at a later point to plug a leak. It looks like weatherstripping was a huge concern back when this place was renovated.

The reason there is a mudring is because the property is piped and most common pipe installs here use 4x4 boxes with mudrings. There are a few single-gang-with-knockout style boxes, but those are usually at the end of switch loops and only contain two #14s.

Don't let the lack of paint on the receptacle throw you off much either as the maintenance guy of the apartment was not in the habit of removing plates to paint. Almost every plate has a small ring of paint around it. That install has been there, foam and all, I would guess, about five years.

It is unknown to me if the other 166 suites in the building are identical with respect to foaming receptacles on outside walls. I assume so. Some of the suite designs that were missing receptacles in certain places (12 foot rule) had them added using wiremold, so whatever work was done, it obviously had to be made to conform to code at the time of renovation.

I should show you guys a very interesting install that I also snapped a picture of from the same complex. One type of suite had a bedroom receptacle directly behind the fridge, and that recept and the fridge recept were in a single box with a mudring on each side. With both plates off you can look through into the other room! Never, ever seen anything like that before but it was clearly original.

Honestly, aside from the foam, i'd say the wiring as a whole is actually pretty good. All of the devices are P&S, not back-stabbed, etc. Not your standard corner cutting, 35 cent, back stabbed, home depot special--which is much more common.

[This message has been edited by jdadamo (edited 08-07-2005).]

Top
Page 1 of 2 1 2 >



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals