Doubled up drywall with metal mesh?

[d3ad1ysp0rk]

Got a leak and some mold, started tearing out the ceiling and discovered two strange things.

1. The drywall was doubled up. Only guess so far was past leaks and they decided it was easier to just put another piece up when they repainted than to repair what was there. No idea why else they'd do it on a ceiling (1st floor of a 2 floor home).

2. Between the two sheets, the edge 1.5" has a metal mesh between the two sheets. I have attached a photo I got of it.

Any ideas on why this was done? Also, what would be your tool of choice to cut through the drywall since it's so close to the wall, and the mesh prevents a handheld drywall saw from doing anything?

 

[The Cobbler]

what you have is gypsum lath and plaster(drywall type backing with rough coat & finish coat ) . the expanded metal is in the corner only.
Now we use drywall & paper ( or fiber) tape in the corners

take a flat chisel & hammer & cut through the metal in the corner . plaster is harder to work with than drywall for sure

 

[Amitygravel]

Yes that mesh can be evil stuff to work around.
IF its feasible , angle grinder with metal cut off wheel , but be prepared for a big cloud of dust that will cover everything unless you dustwall the area you're working in.
You have to be careful of sparks as well obviously.

I like the chisel idea , slower but it would mean a lot less cleanup of the area.

 

[tcianci]

What you have there is a rock lath and plaster job. Rock lath and plaster finishes were sort of an evolutionary step to where we are today with blueboard and skim coat plaster jobs. The rock lath you have there is a product that took the place of old wood lath. The material is 16 x 48 x 3/8" thick and was nailed to the studs in a running bond or "brick" pattern. Over this material, a coat of gypsum plaster was applied. On top of the gypsum plaster coat, a coat of white hydrated finish lime was applied. That's the coat that everyone sees and refers to as plaster. The typical finished thickness of this system in 3/4 inch. The lath is 3/8 and the plaster and lime is 3/8. To ensure that the thickness of the plaster was uniform around windows, doors and along the baseboards, a 3/4 x 3/4 strip of wood (usually redwood) called a Plaster Ground was nailed. This allowed the plasterer to strike off his job flush with the strip of wood at these critical areas giving the finish guy a nice even plane to apply his casings and trim to.

The metal you see in your example is called "Corner Rite" it is a black coated expanded metal 90 degree corner. The purpose of the Corner Rite is to prevent cracks along inside corners, much like we do with joint tape today. While a rock lath and plaster job did not use any tape or metal to cover the joints in the rock lath, they did use the Corner Rite on the inside corners. It's interesting to note that the Corner Rite was only nailed to one side of the inside corner and only enough to hold the material in place until it was bedded in the plaster.
Corner Rite is pretty easy to tear through with a wide chisel or a flatbar.

 

[-Brent-]

If it's about an inch thick and the mesh is in corners and joints, what you have is plaster board. It was the material between lath and plaster and sheetrock. The first sheet has holes in it, the second is like a heavy sheetrock sheet made of a denser rock-like material.

 

[joncro55]

That mesh doesn't look like its plastic coated, I think it is just plain old woven wire cloth metal material judging by the photo - in the past, I have spoken with manufacturers on this stuff - www.bwire.com - and they always say to use aviation snips on this material. As far as the drywall and everything else - how about SAWZALL?

 

[383 240z]

I've torn literally tons of that hell on earth from my home. I usually cut the expanded metal "tape" with my trusty (after that job) dusty 4.5" cut off wheel. In some places, I just hammered the heck out of the wall side, leaving the ceiling side alone, then hammered away with a 2-3" wide brick cutting chisel. Keith

 

[waggie]

regarding the metal mesh...

It's NOT only in the corners. At my house (built in 1957), it covers the entire wall. I just demo's two entire walls, and no matter where we cut, the expanded sheet metal was there.

 

[JayCrash450]

I love plaster walls. Many think I'm crazy but plaster not only has nostalgia to me (my dad was a plasterer for 30 years) it has way better sound transmission properties and heat insulating properties. I also like the feel and solidness of it. The 1/2" drywall hung in today's homes feels cheap.

Admittedly, plaster is a pain to patch and cut. I still prefer it. If I ever have the money to have a custom built house, I'd rather have plaster. It's legit.

 

[Ross/Kzoo]

I love plaster walls. Many think I'm crazy but plaster not only has nostalgia to me (my dad was a plasterer for 30 years) it has way better sound transmission properties and heat insulating properties. I also like the feel and solidness of it. The 1/2" drywall hung in today's homes feels cheap.

Admittedly, plaster is a pain to patch and cut. I still prefer it. If I ever have the money to have a custom built house, I'd rather have plaster. It's legit.

I agree. I've built three houses, the first house was drywall. The next two were plaster and the house next year will be plaster. It will probably be $1500-2000 more but even if it was $5000 more to me it is/would be worth it.

PS A good plasterer is an artist.

 

[Zeke]

Now I know I'm old because I just heard from someone who has never seen plaster and thought all the world was built with drywall.

 

[Cycon02360]

I believe I've encountered the same material while mounting a flat screen TV and installing an inside wall cable organizer kit. Initially, I thought I'd hit electrical wiring, but stud finder showed no such alerts. I've uploaded a pic. I'm contemplating going at this with a saws all with a bi-metal blade. Any feed back or opinions on this course of action would be much appreciated.

 

[rlitman]

I believe I've encountered the same material while mounting a flat screen TV and installing an inside wall cable organizer kit. Initially, I thought I'd hit electrical wiring, but stud finder showed no such alerts. I've uploaded a pic. I'm contemplating going at this with a saws all with a bi-metal blade. Any feed back or opinions on this course of action would be much appreciated.

No. That's what I have in my house. Real plaster on metal lath.

Horizontal metal strips support the metal mesh, which supported the first layer of plaster. That stuff has more of a concrete look to it, and was lightened with perlite. That was then coated over with plaster.

It's a killer to get through. I've had ok luck cutting in boxes using my Fein tool. It wears through any blade quickly, but you can re-grind in a large triangle shaped tooth that will do the trick and save you from buying dozens of blades.

 

[campernut64]

No. That's what I have in my house. Real plaster on metal lath.



Horizontal metal strips support the metal mesh, which supported the first layer of plaster. That stuff has more of a concrete look to it, and was lightened with perlite. That was then coated over with plaster.



It's a killer to get through. I've had ok luck cutting in boxes using my Fein tool. It wears through any blade quickly, but you can re-grind in a large triangle shaped tooth that will do the trick and save you from buying dozens of blades.

My house is the same stuff. I like it. Much quieter than regular drywall. Every room in my house was papered over the plaster. Wife stripped it all to paint. I hated to paint over such nice workmanship. Glass smooth.
Ditto other comments on a Fein Multimaster or like tool. Waited years to buy one then kicked myself for not buying sooner. It’s the must non destructive saw I have. I’ve used mine a bunch since buying this house. Worth every cent in labor savings and unneeded plaster destruction.

 

[rburke65]

I think the metal mesh came after the wooden lath with the horse hair mixed into the plaster scratch coat. Then came the wire mesh. Then drywall. Wire mesh is a real pain to cut in electrical outlet boxes for rewire and or update.

 

[yeldogt]

There have been many types of lath .. some metal with a backer and others w/o. Plaster in good shape is great .. and can be patched with no problems.

Cycon - You do not want to use a Sawzall unless you use a very fine blade. All you have to do is catch it once and you can easily crack the wall. They tend to bang all over the place.

You soul be able to snip the lath with metal shears

 

[Angelfire]

Previous owners were attempting to create a faraday cage to stop surveillance
from the aliens.

 

[tcianci]

Previous owners were attempting to create a faraday cage to stop surveillance
from the aliens.

Only if you ground it.

 

[James-W]

We had wire mesh in the corners of our house too, but we ripped it all out and put up drywall. I used 3 foot wrecking bar to rip it down and it worked reasonably well. On some longer pieces we had small chain with small hardened steel hooks that we could attach to the mesh and then wrap the other end of the chain around the wrecking bar. A buddy was helping us and with two of us pulling it came down without too much trouble.

 

[ddawg16]

Sawzall with a metal blade makes quick work of it

 

[Lelandwelds]

If we are talking demo, a wrecking bar will get most of it down quickly. I also used a roofing removal flat spade thing. I never used mine but i have yet to find much a sawsall will not get through.

 

[campernut64]

Ditto on the Fein Multimaster and it’s ilk. Try carbide blades. I too waited far too long to buy. Bought one when I bought my present gypsum lath and plaster home. Let’s you be rather surgical with your cutting saving a lot of further carnage and much less dust in the air. Also nice for removing old nail in electrical boxes for rewiring without making huge holes. Use the “hacksaw” blade and slice the nail tab or nails off of stud to remove.
Love plaster too. House done in 1948 addition in 1960. Other than bathrooms everything was wallpaper and was never painted. Wife stripped whole house to bare plaster. Amazing how smooth and polished the finish is. Hated to paint over great craftsmanship.

 

[paredown]

I too have fought with that stuff--we've got the interim version that looks like what you posted (post wood lath) where they used gypsum 'boards' (2' wide) nailed up, then the metal mesh in all the corners, scratch coat and then finished plaster.

If I'm patching up to an wall and don't want to strip it out fully, I've used a hand grinder with a cheap wheel to get right up in the corner, and then trimmed back any 'tails' left if you need to get a new piece of drywall slid into the corner. Often times you will find they used smooth shank plaster's nails to tack it in--those need to come out before you start refinishing.

I've used my HF multi tool to trim back on the finish coat of the wall that I'm saving--use a laser line to get a fairly straight cut, and then tape new to old. I used hot mud for these patches--not as robust as plaster, but I can get a decent job where you can't tell I was in there. Plaster will eat blades for the multi tool, so I buy bulk on Amazon...

Sometimes on the corners you can get a hold of the metal and rip it out.

(Ive done a fair bit because I had to insulate a bunch of ceilings by tearing out the old drywall board/plaster combo and didn't redo all the internal walls...)

PITA--wear gloves, but you will still end up bleeding.

 

[paredown]

...
Love plaster too. House done in 1948 addition in 1960. Other than bathrooms everything was wallpaper and was never painted. Wife stripped whole house to bare plaster. Amazing how smooth and polished the finish is. Hated to paint over great craftsmanship.

Yes--if we could afford to, I would be putting up the special drywall and get my repairs plaster coated--nothing beats it for durability, sound dampening--even better for regulating internal moisture, since it will hold more moisture than drywall.

But my reno is a budget affair--plus a lot of the plaster had already failed from roof leaks, and been replaced by drywall, so I tell myself that what I'm doing is no worse (and often better) that what the PO's did...

 

[dogdog]

don't use multi tools ... they'll be destroying expensive blades , not the right tool for this job... just take a chisel hammer... those mason hammers, knock the old plaster sand off the metal, and cut the metal with a grinder... situation permits, and common sense things apply.

don't over complicate these things.