Replies

1. 
   JimB | Feb 20, 2012 10:42am | #1

   If you don't mind the possibility of a little extra repair when

   the time comes, just cut it out with a jigsaw or reciprocating saw.  If the wall has wood lath, there's a potential for the saw to bind and/or vibrate loose lathe and cause the plaster to break beyond where you want to remove it.  That can be minimized by deeply scoring the cut-out perimeter with a utility knife.

   It's also much easier to get a clean cut if you can manage to align your horizontal cuts with the gap between the lath.

2. 
   Tim | Feb 20, 2012 02:15pm | #2

   I have an older property that has lath and plaster walls. I rewired it and added forced air, and was afforded the opportunity to cut a few holes in the plaster walls and ceilings.

   Three ways I found to do so, each with drawbacks. Any blade you use will be destroyed.

   One - using a masonry bit, drill a series of closely spaced holes, break the plaster in between and clean up the edges with a drywall saw. Depending on the condition of the lath, you can clean up with a sawzall, but I prefer to cleanup by hand saw. Less collateral damage. The hand drywall saws cost less than $10 and works well if you use the tip to cut through the plaster and the teeth to cut the lathing.

   Two - this is very messy and you must protect your eyes with goggles - plunge cut with a circular saw. This is quick and makes the best cuts but buy a cheap blade because it will be junk quickly.

   Three - for small, more precise openings, when limited mess is very important, score the cream surface with a utility knife or the sharp tip if the drywall saw, turned sideways, and do all of the cutting a with a hand dryall saw.

   I preferred method one for most of the holes I cut in the ceiling and method three for the walls, mostly for 2x4 electrical boxes to install switches and receptacles.

   Good luck.

3. 
   Norman | Feb 20, 2012 03:57pm | #3

   Try an ocillating saw

   I recently had to put a hole into a p & l wall, a perfect excuse for the Dremel MM knock off the DW got me for Xmas year before last.

   I used a wood cutting blade, which worked very well. A very clean cut with little dust. Much better than a jigsaw, sawzall or roto-zip, all of which I have used before.

   Unless it was a huge hole, this would be my first choice in the future. The Harbor Fright version will cost less than $30.00.

   Good luck.

1. 
   calvin | Feb 20, 2012 06:34pm | #4

   Another vote for a Multimaster tool

   I used the diamond blade to cut the plaster, then changed to a wood blade, cutting just inside the plaster line to preserve the blade.

   If using a recipro cutting or jigsaw-I mounted a pc of ply with vertical slots cut in (short of the top and bottom.)............the width of the cut I wanted to make-right over the location.  I screwed through the ply into a couple of the lath.   I had first drilled a hole big enough for a blade to fit in.

   With the ply firmly mounted to both sides of the cut, there was no ripping and tearing of the lath-which is what ruins a cut with all the vibration.  Like mentioned-it ruins a blade fast cutting through the plaster.  If you can get rid of the plaster and base morter, you might get some mileage out of the blade.

   Staying close to a stud certainly helps, in at least half the cut.

   Nothing beats the multimaster in the years since I got it.  Now that there's cheap models, no reason not to buy.  I still believe those wanting to use them forever should go the excellent route, but there's the price concious that might get close with the low dollar brands.

1. 
   JimB | Feb 20, 2012 06:48pm | #5

   Calvin, good tip

   I never thought about this, but it seems obvious now that you've mentioned it.  I'll give it a shot.

   "If using a recipro cutting or jigsaw-I mounted a pc of ply with vertical slots cut in (short of the top and bottom.)............the width of the cut I wanted to make-right over the location.  I screwed through the ply into a couple of the lath.   I had first drilled a hole big enough for a blade to fit in."

1. 
   calvin | Feb 20, 2012 07:02pm | #6

   Jim

   This was on a wallpapered (be careful, I don't have any more............) wall.

   The jarring of a sawzall or jig saw happens when you least suspect it, and is one violent heart stopping action for a remodeler.

   and then the downside of doing it by hand-(which still can do damage, but at least you get a chance............to stop) it is time consuming ...............

   Remember of course, the last cut through the last pc of lath is still there and ready to jar the crap out of your work.  As I remember it better now-I believe I may have screwed into each lath, within the cut out area and made the horizontal cuts through the plaster only(I urge you to not cut horizontal through the lath if you can help it...........I think.)   I know I've done it because of size of cut and it even makes sense because it can hold that horizontal cut on a wood backing (the lath).

   And don't forget-It might or could fall under the RRP regulations!

1. 
   JimB | Feb 21, 2012 06:23pm | #11

   Amen! It seems like there's seldom a problem unless

   you're working on wall or ceiling that that can't be easily repaired and nearly always on the last piece of lath--just when you when you think you've got it made.

   I avoid trying to cut lath horizontally as much as possible.

   Screwing into each lath would definitely be worthwhile if you really had to be right. 

2. 
   calvin | Feb 21, 2012 07:11pm | #12

   I cannot remember much

   but I do remember success with that and other methods.

   and I suppose I should admit that some attempts, no matter what they are-do fail.

   Here's an interesting lath I found a couple yrs ago.  I have since read that this is a "common" occurrence or method once used.  I'm sure it was probably due to "what was around" or what tools were available to provide the surface for the plaster covering.

   View Image

   The different colors and textures show the different boards that were I'm thinking-nailed off along the top or bottom, then split and spaced-nailed off again and the process was repeated.   Fasten, split, nail................till the board was applied with spaces made from the splits.   These were pretty much thicker than the usual milled lath otherwise used (which were much like the bndls of lath you can get today or the snow "fence" of the 60's).

   View Image

   You can see that the ooze was not very uniform.  All the wood was rough cut, so there's some adhesion made up by the fuzz on the wood itself.

   In the case of the door opening I made on the right, I fastened the lath to my new framing b/4 cutting the interior open and demoing the the unwanted plaster.   But this stuff at 1870 vintage or so was some dry plaster-loosly holding on to the lath and thinly applied. 

   So, some patching was necessary to the interior.

3. 
   JimB | Feb 23, 2012 07:19pm | #13

   Very interesting. I've not worked on any plaster lath that was

   quite that rough.  Thanks for posting the pictures!

4. 
   calvin | Feb 20, 2012 07:06pm | #7

   J

   We've been assuming a wood lath backer.  However, in the 30's I've often found gyp lath, the precursor to drywall as a backer.  There usually was a diamond metal up near the ceiling corners as well as inside corners.  the "corner bead" was also much wider, often with a diamond metal flanking each side.

   What is your backing?

1. 
   ranchodiablo | Feb 21, 2012 01:54pm | #9

   The backing is wood lathe for sure.

   i think I will go and buy an oscillating saw.  I have been waiting for an excuse to buy one and this seems like a good reason.

   Also, the wall and the ceiling were never bridged together in any way, so there is a small gap all the way along.   I am planning to use drywall corner bead (the kind with the metal or the plain type) to fix this.... Does that sounds alright?  I know it's a lot of work, but then it will be done in a decent fashion for the first time ever.

   Cheers

1. 
   calvin | Feb 21, 2012 02:02pm | #10

   rancho

   Cheers back at you.

   Choose wisely on the oscillating saw-go high or low, but might do some homework-some of these have burnt up with use.  Blades are all  over the place and some do good, some not.

   I think FHB had a review on some different brands a while back.

   Corner work-I would stay away from the metal imbedded paper tape-I used to use that quite a bit and almost every time-you'd get a bubble or if too vigorous in sanding-go right through the paper.

   I'd use fibreglas tape-stick it on and mud it up....................

   or

   as on plaster, not usually a good stick-so try it first.

   Regular paper joint tape.

   Or experiment with No-Coat tape.

   With all, I use the real Durabond for the first coat.

5. 
   hammer1 | Feb 21, 2012 10:52am | #8

   There is also metal lathe that was used, tough stuff, like expanded mesh. I'd use a Multi-master type tool and just remove the plaster to see what's underneath. Cut the outline then make a series of grid cuts and chip out the plaster.