- Occupation
- Licensed Electrician
Don't laugh. Great Stuff is amazing! It holds things in place remarkably well. A few sections of my house for example.
cutting in a masonry box. epoxy or hydraulic cement
- Thread starter JJWalecka
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It's polyurethane based, as are a lot of adhesives. The 3M 550 and some of the other adhesives mentioned earlier are also. Gorilla glue is another example... and it foams when exposed to the instructions recommended amount of moisture?which is the curing agent in many polyurethane adhesive types.
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
foam in a can is a great adhesive. get the non-expanding stuff for this kind of work though.
K8MHZ
Senior Member
- Occupation
- Electrician
As someone mentioned, the foams and the like are impossible to get off your skin or clothes once dried.
I found that out the hard way with Great Stuff. I had to tear patches of my skin off to remove it from my hand and arm. The only known solvents for dried Great Stuff will destroy skin. Basically, only acids, and not even all of those, will dissolve Great Stuff.
That's why I prefer the concrete products if at all possible.
I found that out the hard way with Great Stuff. I had to tear patches of my skin off to remove it from my hand and arm. The only known solvents for dried Great Stuff will destroy skin. Basically, only acids, and not even all of those, will dissolve Great Stuff.
That's why I prefer the concrete products if at all possible.
kwired
Electron manager
- Location
- NE Nebraska
Non expanding stuff needs to be out of the way from physical abuse though as it is much easier to remove cured product of of surfaces
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
I would not refer to either variety of foam sealant as being easy to remove at all.
I find the non-expanding version is a lot less messy because it does not sneak out everywhere. I guess it is technically "minimally expanding" rather than non-expanding.
jxofaltrds
Inspector Mike®
- Location
- Mike P. Columbus Ohio
- Occupation
- ESI, PI, RBO
Question? If this Great Stuff is combustible what if it enters an opening in the box? Violation?
Since it is combustible would extension rings be required even in brick?
"Note: GREAT STUFF? Insulating Foam Sealants are combustible, so it's very important that all electrical switches are turned off before starting your project. Also, never apply foam to exposed wire or inside an electrical box. Be sure that wires have a protective covering before applying."
http://greatstuff.dow.com/where-to-use/living-space/electrical-outlets/
Since it is combustible would extension rings be required even in brick?
"Note: GREAT STUFF? Insulating Foam Sealants are combustible, so it's very important that all electrical switches are turned off before starting your project. Also, never apply foam to exposed wire or inside an electrical box. Be sure that wires have a protective covering before applying."
http://greatstuff.dow.com/where-to-use/living-space/electrical-outlets/
Everything is combustible if you get it hot enough
And how hot is an arc flash?
BTW, plastic boxes, conductor insulation, and plastic sheathing are also combustible, though some have flame retardant characteristics.
jxofaltrds
Inspector Mike®
- Location
- Mike P. Columbus Ohio
- Occupation
- ESI, PI, RBO
Everything is combustible if you get it hot enough
And how hot is an arc flash?
BTW, plastic boxes, conductor insulation, and plastic sheathing are also combustible, though some have flame retardant characteristics.
True.
The reason that I ask is because if an inspector tried:
(B) Installation and Use. Listed or labeled equipment
shall be installed and used in accordance with any instructions
included in the listing or labeling.
For it being 'in' the box he could not use that as a violation.
I don't think this could be used either.
314.20 In Wall or Ceiling. In walls or ceilings with a
surface of concrete, tile, gypsum, plaster, or other noncombustible
material, boxes employing a flush-type cover or
faceplate shall be installed so that the front edge of the box,
plaster ring, extension ring, or listed extender will not be
set back of the finished surface more than 6 mm (1?4 in.).
In walls and ceilings constructed of wood or other combustible
surface material, boxes, plaster rings, extension
rings, or listed extenders shall be flush with the finished
surface or project therefrom.
Seriously now how much if any would you let come into the box before failing it for lowering the cubic inches?
I likely wouldn't... not being an inspector. :blink:
If there was a substantial amount, I'd insist on the "substantial" being reduced to a minimum. After it has cured, its not hard to remove all but what's bonded to surfaces.
kwired
Electron manager
- Location
- NE Nebraska
When I have tried to add new cables through holes that were sealed with the minimal expanding foam the foam pops right out of the hole fairly easily. You usually are going to drill new holes if they use the regular foam or you will risk damaging existing cables trying to get through.I would not refer to either variety of foam sealant as being easy to remove at all.
I find the non-expanding version is a lot less messy because it does not sneak out everywhere. I guess it is technically "minimally expanding" rather than non-expanding.
It maybe gives off a combustible gas from either propellent, part of the expanding process or both, but that is temporary, didn't read the instructions but am willing to bet they say to use in a well ventilated area as well.
Should some get in through a hole in the box it is usually pretty easy to trim it off, if the box is literally filled with the stuff - the person doing the application needs flogging:happyyes:
growler
Senior Member
- Location
- Atlanta,GA
Since Jay is probably getting paid for this work that would make him a professional.
Many an amateur may end up doing a better job because they are not so interested in the time it takes or money.
The word "amateur" has nothing to do with one's abilities but motivation. We pros work for money.
kwired
Electron manager
- Location
- NE Nebraska
Understood, but I think by using the word "amateur" it was mostly intended to mean inexperience with hydraulic cement.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Maybe "dabbler" or someone "inexperienced" would have been a better choice of words. Amateur astronomers and amateur radio operators are good examples of potentially matching the skill level of professionals.
Tapatalk!
Tapatalk!
texie
Senior Member
- Location
- Fort Collins, Colorado
- Occupation
- Electrician, Contractor, Inspector
Gosh, maybe I'm just an old timer, but every job I was ever on, the boxes in block were set with mortar mix. The same material used for the rest of the wall joints. No different than sealing around a mud ring in drywall where you would use the same mud as the drywall seams. Why non earth would you use an entirely different material than the rest of the seams/joints?
Other types of materials such as silicone make zero sense to me. Even a spec of it that gets on the block will render it unpaintable.
Other types of materials such as silicone make zero sense to me. Even a spec of it that gets on the block will render it unpaintable.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Keep in mind though that mortar will not seal out water!
Are we talking about the interior or exterior of a wall?
Tapatalk!
Are we talking about the interior or exterior of a wall?
Tapatalk!
petersonra
Senior Member
- Location
- Northern illinois
- Occupation
- engineer
mortar mix is fairly easy even for amateurs to work with.
hydraulic cement is tough for even a good mason. that is why they mix it up in thumb size batches.
hydraulic cement is tough for even a good mason. that is why they mix it up in thumb size batches.
texie
Senior Member
- Location
- Fort Collins, Colorado
- Occupation
- Electrician, Contractor, Inspector
Well then, "Houston...we have a problem", as then there are a zillion walls out there made of masonry that must not be keeping out water.
I would bet there is not an AHJ out there that would not approve a masonry box set flush in the block, secured and sealed with mortar for, say, an outdoor recep. with a gasketed weatherproof cover. Even the king of crazy specs, that would be the feds, would accept this.
Oh, wait! Now I have been sucked into this no brainer discussion.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
It all depends on how well you want to seal out water. One reason for the surface of mortar in the grooves between bricks to have a concave curved or V surface is so that rainwater does not pool against it.
Horizontal surface masonry joints either need to be caulked or to provide for water to drain away from the far side.
Try sealing a swimming pool or tub with mortar. Even portland cement concrete absorbs moisture to some degree. Mortar is worse.
Tapatalk!
Horizontal surface masonry joints either need to be caulked or to provide for water to drain away from the far side.
Try sealing a swimming pool or tub with mortar. Even portland cement concrete absorbs moisture to some degree. Mortar is worse.
Tapatalk!
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Fulthrotl
~Autocorrect is My Worst Enema.~
- Occupation
- E
i've used hydraulic cement exactly once in 35 years. it didn't seem all that difficult
to work with, any more that 5 minute hot patch mud is... :roll:
you just need to get it in place before it goes off.
i can't think of any reason i'd use it anymore. i've been hooked on the 3M 550 urethane for
the last year or so. i don't use silicone or latex caulk at all, and i buy the 3M by the case.
zero leaks, paintable, flexible, strong. you've got white, gray, and black unless you want to buy
a couple pallets of the stuff, then they will do any pantone color you have a number of.
comes in a metal tube, with a pop top end, so it'll never go off and you have a dead tube.
you just have to put on the little blue nitrle mittens before cracking the tube open.
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