Cutting holes in interior walls

Page 1 of 2  
my house has walls that are very thick and heavy. Cutting electrical outlet holes and ceiling holes is very difficult. Using a saws all with a big tooth demolition blade, I get maybe 20 inches before the blade is flat. Ceramic blades are much worse. Am I doing it. Right? I find finer tooth blades are worse.
Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Let me guess; you live in Rockview State?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Where is Rockview State, I've only heard of Stateville, in Joliet, IL
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
hr(bob) snipped-for-privacy@att.net wrote the following:

--

Bill
In Hamptonburgh, NY
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
willshak wrote the following:

--

Bill
In Hamptonburgh, NY
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I got the escape part - I thought he might be refrring to a particular prison, for example, Stateville in Joliet IL is widely known.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 28 May 2011 12:27:39 -0700 (PDT), "hr(bob) snipped-for-privacy@att.net"

He's in PA. If he were trying to escape from Stateville, he wouldn't be asking now. ;-)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
zek wrote:

I assume that you probably won't write back but .....,
What are the walls made of? Is it an old house? Are the walls made of plaster over wooden lath? Are they made of some other type of masonry product?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Some kind of double layer material maybe plaster. The inner layer is very gritty like sand.
I was cutting cement and cinder block with a dry diamond blade. I know all about dust.
Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
zek wrote:

Thanks. Sounds like they are plaster walls -- a thinner layer of white finish plaster over top of a thicker layer of gray or light brown sandy/gritty "rough coat" plaster.
Under that, attached to the rough coat plaster, should be either wood laths or maybe a metal lath/mesh.
If it is wood lath underneath, the saw blades will last longer but it's a real pain using a sawzall because the wood laths vibrate back and forth and break up the plaster pretty far around the outlet hole you are trying to create. If it is wood lath, my guess is that the plaster is destroying the demo blades because they are mostly made to cut wood.
If you happen to have metal lath under the plaster, the metal will kill the sawzall blades faster.
I have found that cutting outlet holes in lath and plaster walls is a real challenge. If there is wood lath underneath, sometimes you can use the angle grinder that someone suggested, or even one of those vibrating Dremel tools, to cut just the plaster and break it out down to the wood lath. Then use a small saw (even a hand saw for cutting drywall) to carefully cut off the wood laths while holding each lath so it doesn't vibrate back and forth while you cut it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

Even carbide blades will do it, but as you say, dusty as all get out. You could do that and square the corners with the sawzall. Personally, having cut pavers with circular blades, I'd rather just buy more sawzall blades and live with that. Maybe zek should try different blades. Maybe these. (Amazon.com product link shortened)
--Vic
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

What is the material that you're cutting? Other than outlet boxes, what are you cutting on the ceiling?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I have cut ceiling recessed lights and an attic entrance. The round holes need a smaller blade which goes bad fast, there is no lath or metal or wood. I'll see if I have a piece to take a photo.
Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I have cut ceiling recessed lights and an attic entrance. The round holes need a smaller blade which goes bad fast, there is no lath or metal or wood. I'll see if I have a piece to take a photo.
Greg
I think what you have, is rock lath plaster, it's like a layer of 1/2" sheetrock with holes in it, that's plastered over. The plaster keys into the holes. It winds up about an inch thick, and is often very hard. I usually cut outlet holes in that with a hand keyhole saw. It's work, but you're getting a clean rectangle with no big chips. For the recessed lights, Lenox makes carbide hole saws that work great. The only down side is the dust. I cut a basketball in half, and drill a hole in the center of one half, slide it over the hole saw, which helps to trap the dust and plaster particles.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

.
Picture".........
http://zekfrivolous.com/wall/wall.JPG
Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

...
I'll say one thing, makes good soundproofing!! Just a hair over 1 inch thick.
Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'll say one thing, makes good soundproofing!! Just a hair over 1 inch thick.
Greg
I just did a recess lighting job in a place that was an estate garage, converted into a house about 50 years ago. all the ceilings were wire lath with about 1 -1/2" thick very hard plaster. I cut 14 - 7" holes with the Lenox. It worked really well. I don't think it dulled it at all.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Picture".........
http://zekfrivolous.com/wall/wall.JPG
Greg
Looks like rock lath, but I've never seen the plaster coat that thick. It looks more like cement than plaster. OK, so you live in a bunker. If you're near tornado alley, that's a good thing. Look at the bright side, when you're done with this project, you'll have the biggest biceps in town.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

...
I'm near Pittsburgh. House built around 1953. We have had tornados lately. I also have basement. I can see where the walls have bent the 10 inch joists down over the years. Another trouble house was built with a main bean of 4 8X2 s. I reinforced that. I'm still leveling.
Greg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'm near Pittsburgh. House built around 1953. We have had tornados lately. I also have basement. I can see where the walls have bent the 10 inch joists down over the years. Another trouble house was built with a main bean of 4 8X2 s. I reinforced that. I'm still leveling.
Greg
*That is a heavy duty wall. I suggest a RotoZip tool with maybe a cement board bit or possibly a diamond bit. For a quick square cut, not-too-accurate of a hole, an angle grinder with a diamond blade will be fast, but dusty. I have a little Makita cordless saw. I can put a 3" diamond blade on it for cuts such as yours. The 9.6 volt battery doesn't last too long though.
The hole saws that RBM suggested are perfect for recessed lights. They are available in several sizes to accommodate different manufacturers. You can also get tungsten carbide hole saws the same size as round electrical boxes. Check McMaster.com
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

Related Threads

    HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.