Cutting holes in plaster walls

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Chris Simms

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Cohutta GA
I have a rewire to do in a couple of weeks and the house has plaster walls and ceilings. The AHJ tells me that I will have to add recepts where they currently are not and that means a lot of new holes. I need to know of a good way to cut these holes without cracking the plaster . I don't think that a sawsall would be very gental but a keyhole won't work either.
Any ideas?
Chris
 
Swiss cheese the perimiter of the hole with a tapcon bit. Don't put the drill on hammer. Then cut with your saw on the in strokes only.
 
Having done many rewires my question is where does he find in code to make you add any ? Your house should be grandfathered in.Are you talking rock lath plaster or the wood type ? I would drill small holes at corners and use roto zip.Your in for a fun time.I use to allow 2 man hours per opening.That was 1 hour for me and 1 hour for helper.
 
roto zip with a plaster bit set deep enough to cut plaster but not the lath, then change to wood cutting bit to cut the lath. that is the only way I would take on plaster walls...
 
chris kennedy said:
Swiss cheese the perimiter of the hole with a tapcon bit. Don't put the drill on hammer. Then cut with your saw on the in strokes only.

That is good advise. I have also scored the plater very gently with a skinny screwdriver and gently tapping. You can try scoring the surface with a knife but the drilling around the perimeter works very well.
 
ItsHot said:
I place the receptacle outlet boxes horizontal in the baseboards that way I don't have to cut plaster! :rolleyes:

Not if I were the customer, that would really set me off it you started cutting into my woodwork
 
no complaints yet

no complaints yet

ultramegabob said:
Not if I were the customer, that would really set me off it you started cutting into my woodwork
I have not gotten any complaints yet! I have actually been requested to do this in a lot of old historical homes!!
 
chris kennedy said:
Swiss cheese the perimiter of the hole with a tapcon bit. Don't put the drill on hammer. Then cut with your saw on the in strokes only.

What works great everytime for me: Swiss cheese the perimeter of the hole then go back to the first hole with same drill bit and "rock" the drill/bit in a radial fashion, up and down for the vertical cuts, then do again horizontally for the horizontal effectively connecting the holes. After this, cut through any remaining areas by holding the drill with sharp bit at a 45 degree angle to the wall and let the center section of the bit cut the last bits out by pushing it sideways thru the perimeter. I won a $20 bet that I could do 5 consecutive holes perfectly this way before the seasoned journeyman I was working with could complete 3. :cool:
 
ItsHot said:
I have not gotten any complaints yet! I have actually been requested to do this in a lot of old historical homes!!

And just what do they do with the old box ? Fill it up with plaster and then repaint room ?Few people want that extra job and cost.
 
A lot of older homes have fire blocking in the walls.
That's a lot of fun when trying to get a wire down from the top.....;)

You'll probably need some drywall mud and tape, plus a few small pieces of drywall....I've always repaired my own holes.

steve
 
Well, I do a lot of this kind of work, and I see the general term "plaster" meaning what's essentially 3 different types of wall finish. The first is super hard, more like portland cement, with a lighter skim coat over it. You can't really "crack" this stuff unless you're really screwing up. I cut it with a Sawzall plaster blade (perfect triangle teeth) in a hand saw.

The second general type of plaster is much like the first, only the scratch coat is not nearly as hard and the top coat is much the same as the first type. This kind is easier to pull out extra chunks of plaster if you hand saw it, so I use a RotoZip plaster bit on it.

The third type was favored in lower end homes, and is a scratch coat only. It is very soft, and you'll have huge chunks of plaster falling off the wall if you aren't gentle. I swear this stuff was more like sand and lime mixed with water. Really crumbly stuff. Use the RotoZip plaster bit and hope for the best with this type.

No matter the type, I highly recommend the SmartBox or Arlington's One-Box for doing this sort of renovation work. The softer and older the plaster, the less likely you are to achieve a good long term result with the typical old work box or metal boxes with Madison straps. Consider the SmartBox or Arlington's One-Box.
 
I am still wanting to know why he needs to add any.Here all thats required is for me to rewire existing.They will not let you change locations.Grandfathering should come into play here.Will say its a dirty job but days go fast.Extra fun if people with kids still live in it.
 
Jim W in Tampa said:
I am still wanting to know why he needs to add any.Here all thats required is for me to rewire existing.They will not let you change locations.Grandfathering should come into play here.Will say its a dirty job but days go fast.
The International Existing Building Code and the International Property Maintenance Code (both of which are in force in most states) have these sorts of requirements. Rennovation can trigger them.
 
Jim W in Tampa said:
I am still wanting to know why he needs to add any.Here all thats required is for me to rewire existing.They will not let you change locations.Grandfathering should come into play here.Will say its a dirty job but days go fast.Extra fun if people with kids still live in it.
Over 40% renovation has to bring entire house up to current code by me.
 
Sawsall will grab any lathe that may be present and rip out a nice section.

Diamond blade/grinder cuts clean lines but REALLY kicks up the dust.

I haven't used my rotozip on plaster...seems like it would work great with the proper bit. Lots of dust here also.

If it's only an outlet or two, I just work at it with whatever tools are handy. 1/4 drill bit, flat screwdriver,tinsnips, old drywall saw etc. Very little dust this way.
 
220/221 said:
Sawsall will grab any lathe that may be present and rip out a nice section.

All kidding aside, do you actually encounter many buildings in Phoenix with lath and plaster? My impression of Phoenix was that none of the houses there looked old enough to be of the lath and plaster vintage.
 
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