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#159488 - 01/29/07 02:32 PM Crumbling Plaster Batman!
Happi_Man Offline

Registered: 06/12/02
Posts: 213
Loc: Columbus, Ohio - USA
So what do you say to a homeowner after old working an outlet into a 100 year old plaster wall leaving a less than desirable...well...hole.

This was one of the worst case scenarios but today buy the time we worked the wire down to the existing box and fumbled with getting it into the box enough plaster had crumbled away leaving a large gap next to the outlet...

My mind says...risks of the conscience says fix it for the sake of your customer...I just can't even think of how to explain the situaton to someone who I know kows very little about remodeling type jobs...

What would you say to this customer and how would you handle this situation??

Business, Office, Estimating, Legal:
#159489 - 01/29/07 02:40 PM Re: Crumbling Plaster Batman!
sparky806 Offline

Registered: 12/07/02
Posts: 59
Loc: Shawnee, KS, USA
I would fix it and charge for my time and material.

#159490 - 01/29/07 02:47 PM Re: Crumbling Plaster Batman!
Dnkldorf Offline

Registered: 12/12/04
Posts: 1091
Loc: nowhere usa
Upgrade to Quad box for free?

#159491 - 01/29/07 02:55 PM Re: Crumbling Plaster Batman!
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
Goof plate?
Bob Badger
Construction & Maintenance Electrician

#159492 - 01/31/07 08:12 PM Re: Crumbling Plaster Batman!
DougW Offline

Registered: 06/08/03
Posts: 1083
Loc: North Chicago, IL
Drywall compound

#159493 - 02/01/07 02:40 PM Re: Crumbling Plaster Batman!
Alan Belson Offline

Registered: 03/23/05
Posts: 1801
Loc: Mayenne N. France
I'd brush all loose material and dust out for a good key. Then fill the void/cracks with a stiff paste of "Polyfilla" not sloppy- I think you call it spackle? "Polyfilla" is very strong and expands very slighyly on setting. Leave it slightly below the surface, not proud. I use old expired credit cards for the fiddly bits round boxes, excellent tools! I'm not going to insult your intelligence as an electrician about safety. As soon as it sets, which may be an hour, [ Polyfilla is a mix of hemi-hydrated plasters and cellulose flour ], lay on a finish coat:- Flush to the original plaster surfaces with a sheetrock / [UK plasterboard] finishing plaster, [usually pink], larruped-up with a spackle blade as flush as possible. This stuff sets quite fast. As soon as it seems to be setting, but before it goes right off, run a damp sponge over it. This action raises a sort of thin plaster 'cream', which can be sponged flush into the surrounding old plasterwork. For a super finish, trowel it [ UK "polishing off" ] with the flat [ not edge] of a spackle blade or a plasterer's steel float. Needs paint of course, but the client needs to be told not to paint it till it's completely dry. Notice, no sandpaper - you can always see the marks under the paint. As an alternative to the board finish, I have tried 'Polyfilla fine finish', which is a paste already made up, again using an old credit card in tight places. Works fine, just a bit more pernickerty to get the perfect finish, [ and more expensive ].

Wood work but can't!

#159494 - 02/01/07 05:24 PM Re: Crumbling Plaster Batman!
EV607797 Offline

Registered: 10/25/06
Posts: 756
Loc: Fredericksburg, VA, USA
I rarely encounter plaster in the area where I am, but I feel your pain. I cut my teeth in this business doing service work in New Jersey. I dealt with a lot of plaster and lath in old houses. I don't have a simple solution for your problem, but I do have a few suggestions:

1. When cutting in a box, keep it as close as possible to the stud. They are harder to locate, but worth the extra effort. When cutting through the wooden lath, do it by hand with a coarse-toothed hacksaw blade, not a Sawzall or similar tool. Make the vertical cut to the lath on the side of the box FURTHEST from the stud first. The stud will provide more stability to the lath on the short piece left closest to it. Using a Roto-Zip tool is perhaps the best way to cut this hole.

2. Make sure that the box cutout includes one full lath width through the horizontal center and half a width above and below this full lath width.

3. Score the cutout with a SHARP knife and keep this scoring well within (1/8") of the actual necessary opening. If it's a tricky installation, then narrow it to 1/4" from the final opening.

4. Get the cable(s) fished in THEN prepare your final opening for the box. Again, a Roto-Zip tool will make the fine-tuning of the opening easier, but you'll need to leave the cable(s) inside the wall cavity while you do this. Don't let them slip away!

5. If you follow this procedure, all you should need to carry with you is a tube of basic toothpaste to cover basic cracks or chips that might occur during the final box placement that can't be covered by the plate.

True, it takes a LOT longer to cut the opening twice, but you will eventually get a feel for it and only need to cut once.

[This message has been edited by EV607797 (edited 02-01-2007).]

"But the guy at Home Depot said it would work."

#159495 - 02/01/07 08:52 PM Re: Crumbling Plaster Batman!
macmikeman Offline

Registered: 07/16/02
Posts: 718
Loc: Honolulu, Hawaii
What would be nice would be to find some sort of spray on stuff that you could use to hold all that stuff together and not fall apart. Luckly for me, I almost never run into it much. They used to make walls out of tounge and groove redwood around here.

#159496 - 02/02/07 04:52 PM Re: Crumbling Plaster Batman!
Joey D Offline

Registered: 10/10/03
Posts: 263
Loc: Arlington MA U.S.
This is where the roto zip is your friend. I use a tile bit to cut out the plaster then a wood bit to cut the lathe. It is the least damaging way to do it as the cut comes out perfect. Then I follow up with some #4 wood screws.
I also always tell the customer old plaster is just that, old and damage may happen but i do my best to minimize it and would patch it if I did damage. It's part of the job

#159497 - 02/03/07 04:22 AM Re: Crumbling Plaster Batman!
electure Offline


Registered: 12/24/00
Posts: 4226
Loc: Fullerton, CA USA
Using a Roto-Zip tool is perhaps the best way to cut this hole.

It is, undoubtedly.

I'd fix it, unless it was excluded on my bid. Live and learn.

Goof plate?

Bob, you must have an evil twin posing as Iwire!! 314.21

[This message has been edited by electure (edited 02-03-2007).]

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