PDA

View Full Version : What was that dry wall finish receipe again...?



Dev Emch
07-16-2005, 1:57 PM
I know this is a bit off topic so sorry about that.

I am installing a tiny office space in the main shop and drywalling the walls.

Not long ago on this forum, a couple of folks, including I think Per, posted a receipe for mixing up dry wall mud, etc. and then painting this onto the wallboard.

Could someone please repost this reciepe and an explanation as to why you guys use this? I have to admit that I feel a bit stupid for asking this question. Sorry:rolleyes:

Thanks
D.E.

jack duren
07-16-2005, 2:19 PM
"Could someone please repost this reciepe and an explanation as to why you guys use this?"

new one on me :confused: . im still trying to figure out the reasoning behind taking strips of toilet paper and painting it against a wall. a trim carpenter and another construction worker told this looks pretty kool.

personally i cant get a grip on the method :eek: .

personally i wish someone would come up with a method that would make my daughters make up on the bathroom wall look like a FAUX finish. then we would be on to something :D ...jack

Mike Parzych
07-16-2005, 2:37 PM
im still trying to figure out the reasoning behind taking strips of toilet paper and painting it against a wall.

Uhhh...is this sort of finish used in bathrooms maybe?

Per Swenson
07-16-2005, 3:24 PM
Dev,

It was posted in this thread. http://www.sawmillcreek.org/showthread.php?t=21453

By Dino.

Me I just add dishwashing liquid to both the green lid (first coat)

and blue lid (2nd &3rd) of USG joint compound.

What this does is make life real easy when it comes to smooth.

Hope this helps.

Per

Dev Emch
07-16-2005, 3:32 PM
Thanks Per....

What is your process for doing this? I used to skim coat and then sand with a drywall sander. Not a fun time!

Per Swenson
07-16-2005, 3:47 PM
Dev,

It all depends on the job,

If you are working on a finished home,

No sanding. You sponge it smooth.

This also means you have to take care in your

application. You just knock off those nibs with your knife.

Even on New construction no sanding until you are done.

And this job is delegated to the new kid.

You can spackle dust free, they have a sponge just for this job.

Another hint, do only one side of a corner at a time.

Avoid at all costs those corner trowels and think smooth

from the beggining. Don't fuss with it though, one or two

shots and leave it alone.

Hope this helps.

Per

Dev Emch
07-16-2005, 3:51 PM
Thanks Per...

This does help.

Dev

Dino Makropoulos
07-16-2005, 7:23 PM
Hi Dev.
Thanks Per.
The D-Mix is the EZ way to veneer plaster, repairs and restoration.
The problem with ready mix joint compound is that it dries from outside (Air)and creates a skin that makes it impossible to rework the same materials.
Other plasters drying from inside (Setting compounds) and even if you're a pro the best you can do is speed up the job for the next coat. (Because the plaster shrinks.)
The D-Mix was custom formulated by luck first, (no water at the job site :confused: but few extra cans of latex primer) then by many years of testing and more testing. :eek:
After 20 years and no problems reported... yet :rolleyes:
Ok This ez it for the historical back round.

The D Mix Recipe.
For 2-1/2" gallons of JC (joint compound)
1/2 to 1 gallon of latex primer.(PVA is better)
You must use a power mixer until you have a uniform color and until the
D-mix becomes rollable.
Then you can throw into the mix (one small cup of coffee) plaster of Paris
The cup should be the small Dunking Donuts coffee cup or you can treat your self with Starbuck. :D
You mix again for 2 minutes and if needed throw in more PVA primer or some water. The Idea is to make a similar mix to sand-paint.
(medium to heavy soup)
Now you're ready to show off your painting skills. Dip the whole roller into the D-mix and you should cover an area 4"x4'. 12-16 SF.
Keep going few times until you cover an area 10' x 8".
Then you can go back and rough smooth the area with anything that you can use. (Taping knife, straight edge,small 24" level, whatever.)
By the time you rough smooth the area you can go back and show off your plastering skills with a trowel or a large taping knife. :(
Don't worry. Is very EZ. This D-Mix is very forgiving and allows you to rework the same materials without the typical skin or shrink.
If needed spray some water or apply more D-Mix to make it soft and smooth again.
Tools.
100% lambs wool roller only. You can buy one from the local paint store.
Wet the new 9" roller before you use it for 2-3 minutes.
Apply the mix into 3-4 spots ( 1/4 Roll and skip) before you start the actually rolling. Don't try to make it smooth the very first time with the roller.
And don't try to make it very smooth with the first time of troweling.
For smaller or larger areas you can follow the proportions of the original mix.
Area coverage depends on the artist. :rolleyes:
Good luck.
EZ Dino

Tom Saurer
07-16-2005, 9:23 PM
This is new to me...You use this for new drywall being installed? I'm intrigued.

Dino Makropoulos
07-16-2005, 10:13 PM
This is new to me...You use this for new drywall being installed? I'm intrigued.

Hi Tom.
We use the D-Mix for new drywall and for restoration work on historical buildings churches apt.buildings and old houses.
3 man crew can finish a small 1200SF house in a day. The finish is similar to plaster. We're working on video and special tools and formulations to make it even EZier. :cool:
The idea is to eliminate the 3-4 coat applications and the sanding. :cool:

Per Swenson
07-16-2005, 10:25 PM
Dino,

Are you putting this application on regular drywall

or blue board? Folks, around here, Blue board is a treated drywall

that is used as the substrate for plaster. Again not to

be confused with green board which is used in damp applications

such as bathroom walls or any place that does not call for

wonder board. IE any painted bathroom wall.

Per

Dino Makropoulos
07-16-2005, 10:49 PM
.Per,
This thing is good for any surface. No need for blue board.
Dries faster over new drywall but you can adjust as you go.
You can mix the stuff to set slower or faster according to your skills and methods. More plaster of Paris = faster. More PVA and less plaster of Paris = slower.
The receipe that I give out is the safe way for beginers.
For a pro with help is double or triple the amound of plaster of Paris.

Jason Roehl
07-17-2005, 7:24 AM
So are you using this D-mix with or without paper tape on new drywall? Or are you mesh-taping everything?

Dino Makropoulos
07-17-2005, 7:39 AM
So are you using this D-mix with or without paper tape on new drywall? Or are you mesh-taping everything?

On new drywall I use paper tape if I was to finish the job in two days.
And with fiberglass tape if is one day job.
You can use the D-mix for your first coat with a small roller.
The small roller works good for the first coat and the corners.
To make a small 4" roller you have to cut it from a 9" roller with a hack saw.
Don't try power tools here. :rolleyes:

Jamie Buxton
07-17-2005, 11:25 AM
So this stuff is used over sheetrock to emulate plaster?

Umm....When I look at a sheetrock wall and a plastered wall, I can't tell the difference. (Okay, they're both rollered with latex paint.) So what am I missing here?

Per Swenson
07-17-2005, 12:35 PM
Jamie,

A real plaster job, done by a mechanic with 30 years on a finishing

trowel compared to a taped and spackled sheetrock wall is comparing

The finish on my 89 Ford F350 to a Aston Martin.


Yes they both have paint on them ...but.


Per

Corey Hallagan
07-17-2005, 12:42 PM
So if this mixture is used on new drywall, it still has to be taped right?
Thanks,
Corey

Jamie Buxton
07-17-2005, 12:45 PM
Jamie,
A real plaster job, done by a mechanic with 30 years on a finishing
trowel compared to a taped and spackled sheetrock wall is comparing
The finish on my 89 Ford F350 to a Aston Martin.
Yes they both have paint on them ...but.
Per

Per --
So tell me what the difference is. When you look at the two kinds of walls, how can you tell which is which?

Jamie

Per Swenson
07-17-2005, 1:25 PM
Jamie,

First off, let me say there are not too many in America that

can plaster anymore. You will find them in the union halls and

9 out of 10 should be collecting social security. With one guy

in his 30s struggling along. These days you will only find this work

in high end homes where cost is no object.

The difference is a truly flat wall and the way light is uniformly

reflected off of it. And when you see it you will know it.

The other advantage of plaster is the feel of it. The room is stately

quiet, you will get a feeling of substance standing in the middle of

it. Granted this is very esoteric, like standing in a well done Japanese

rock garden but once the difference in perception is realized, you

will never mistake the two again.

Per

Jamie Buxton
07-17-2005, 2:12 PM
Jamie,

First off, let me say there are not too many in America that can plaster anymore. You will find them in the union halls and 9 out of 10 should be collecting social security. With one guy in his 30s struggling along. These days you will only find this work in high end homes where cost is no object. The difference is a truly flat wall and the way light is uniformly reflected off of it. And when you see it you will know it. The other advantage of plaster is the feel of it. The room is stately quiet, you will get a feeling of substance standing in the middle of it. Granted this is very esoteric, like standing in a well done Japanese rock garden but once the difference in perception is realized, you will never mistake the two again.

Per

Hmm.. I've stood in plenty of plastered rooms. Around here, any home built before 1950 or so is likely plaster over wood lath. The walls don't strike me as any flatter than sheetrock walls, but that may be because the homes have 50+ years of settling and movement in them. The rooms don't strike me as any quieter, but that may because they rarely have insulation in the walls and they are in urban areas, so lots of exterior noise comes right in. Add to that many coats of flat-sheen latex paint, and there doesn't seem to be much difference between these walls and sheetrock.

But maybe I'm not making an apples-to-apples comparison. I'm comparing old plaster in old buildings to (good) new sheetrock in new buildings. For the purposes of this thread, perhaps the question should be how a new D-Mix wall would compare to a 3-coat drywall wall, and how they would both compare to a new plaster over blueboard wall.

Per Swenson
07-17-2005, 4:21 PM
Jamie,

We are not discussing the same thing.

I am talking new high end constuction.

Perfect framing with engineered lumber

and brackets. Plaster over Blue board.

Now how the d-mix compares to this,

beats me.

Understand I am talking quality from the foundation up.

The kind of joint Mr. Singer would build.

Per

Dino Makropoulos
07-17-2005, 4:34 PM
Hmm.. I've stood in plenty of plastered rooms. Around here, any home built before 1950 or so is likely plaster over wood lath. The walls don't strike me as any flatter than sheetrock walls, but that may be because the homes have 50+ years of settling and movement in them. The rooms don't strike me as any quieter, but that may because they rarely have insulation in the walls and they are in urban areas, so lots of exterior noise comes right in. Add to that many coats of flat-sheen latex paint, and there doesn't seem to be much difference between these walls and sheetrock.

But maybe I'm not making an apples-to-apples comparison. I'm comparing old plaster in old buildings to (good) new sheetrock in new buildings. For the purposes of this thread, perhaps the question should be how a new D-Mix wall would compare to a 3-coat drywall wall, and how they would both compare to a new plaster over blueboard wall.

Hi Jamie.
The D-mix is easier and faster to apply than a good drywall job (level 5) and can be done by anyone. Is gives you the feeling of a job well done and all the above as per Per. (I like that)
To compare the D-Mix with real plaster or a good veneer plaster over blue board..there is no comparison.
Plastering is simply art and we only have few plasterers left.
The D-mix can bridge the gap of all other ways and the same time can be done by anyone. To give you an idea.
An old church in Hoboken NJ was to be demolished or abounded due to cost required for plaster restoration. $400-$500.000.00.
The D-mix got the job done in one month with only $80.000 including the painting. It is very forgiving easy to learn and very fast.
I pimp this D-Mix technique over the fine homebuilding forum (breaktime) and the reports are amazing. We even have a secret club there.
;) The D-Mix club. Now everybody is asking for more info,videos and special D-mix tools.
No sanding and no special skill required. One day and you can do 2-3 rooms as a beginner

Dino Makropoulos
07-17-2005, 4:41 PM
Jamie,

We are not discussing the same thing.

I am talking new high end constuction.

Perfect framing with engineered lumber

and brackets. Plaster over Blue board.

Now how the d-mix compares to this,

beats me.

Understand I am talking quality from the foundation up.



The kind of joint Mr. Singer would build.


Per

Per.
Similar to veneer plaster over blue board. But without the trouble and skill.
If you visit breaktime you can do a search on D-Mix. To a pro the D-Mix can be a good and Ez way to increase business and profits.

lou sansone
07-17-2005, 4:47 PM
I agree with Per on this one. There is nothing like a real plaster wall. This is especially true in antique houses. I have included a couple of photos of some of the work that I have been doing in my spare time on my home built c1730 in connecticut. As you can see I am one of the old timers who still does plaster and lath. I basically taught my self how, because as Per says " there is no one who does it any more" . The lath photos is a room that is currently in progress. the other room got done a couple of years ago. the loom in the picuture is one of 2 that came with the house as the original equipment. the other one is still in its original location in the attic and is very primitive being of the same vintage as the house c1730. this loom is typical of late 18th century. After plastering the walls they get 2 fresh coats of hand mixed lime and milk whitewash. that is all any of the walls in the house have ever had as best as we can tell.


enjoy
lou

Todd Davidson
07-17-2005, 5:05 PM
Lou~ You never cease to amaze me. Would love to see your work in person one day.

Jason Roehl
07-17-2005, 7:51 PM
To make a small 4" roller you have to cut it from a 9" roller with a hack saw.
Don't try power tools here. :rolleyes:

Don't they sell 4" roller covers there? Around here, I can get 3.4,7,9,12 and 18" roller covers. I suppose to get them all in lamb's wool, I may have to bug the local paint stores to order them. I'm a painter by trade, so this is a very interesting thread.

I'm still a little fuzzy on the whole taping process. Do you coat just over the mesh tape for a coat or two? Do you roll on a coat just at the seams and then bed the paper tape when you use that?

More questions: what happens to the cured D-mix when you drive a nail or screw through it? Does it chip out like plaster? How repairable is the cured D-mix? How durable?

Dino Makropoulos
07-17-2005, 10:54 PM
Don't they sell 4" roller covers there? Around here, I can get 3.4,7,9,12 and 18" roller covers. I suppose to get them all in lamb's wool, I may have to bug the local paint stores to order them. I'm a painter by trade, so this is a very interesting thread.

I'm still a little fuzzy on the whole taping process. Do you coat just over the mesh tape for a coat or two? Do you roll on a coat just at the seams and then bed the paper tape when you use that?

More questions: what happens to the cured D-mix when you drive a nail or screw through it? Does it chip out like plaster? How repairable is the cured D-mix? How durable?
H Jason.
You can use the D-mix for taping before you use it for veneer plaster,
No cracking when you nail on it.
Repairable with more d-mix or joint compound.
Durable similar to joint compound.

Dino Makropoulos
07-17-2005, 11:07 PM
I agree with Per on this one. There is nothing like a real plaster wall. This is especially true in antique houses. I have included a couple of photos of some of the work that I have been doing in my spare time on my home built c1730 in connecticut. As you can see I am one of the old timers who still does plaster and lath. I basically taught my self how, because as Per says " there is no one who does it any more" . The lath photos is a room that is currently in progress. the other room got done a couple of years ago. the loom in the picuture is one of 2 that came with the house as the original equipment. the other one is still in its original location in the attic and is very primitive being of the same vintage as the house c1730. this loom is typical of late 18th century. After plastering the walls they get 2 fresh coats of hand mixed lime and milk whitewash. that is all any of the walls in the house have ever had as best as we can tell.


enjoy
lou

The room looks Real. More pictures from the rest of the house? :)
1730.? I work for free just to see the construction details on this structure.
I restore many old houses in NJ. But nothing this old.
You can learn few tricks by restoring this old house.
Anything to share? In this house molding was installed before the plaster?
Do you install firestops?
Thanks for the pictures. We need more.

lou sansone
07-18-2005, 12:07 PM
hi dino

old houses are sort of fun to work on and you can learn a lot. This one is pretty early. There are many more around 1770's but getting close to 1700 is hard in most areas. molding is normally installed before the plaster and then the plaster goes up to it. much of the house still has its original plaster, some of the ceilings were done over in the early 1800's, and they were not done very will. those I took down and redid properly. Many folks think that early homes did not have any plaster, but that is really a myth. as soon as they could they plastered the walls and ceilings. this house is a plank frame house and so it does not have any firestops. To put "sheetrock" in this old of a house would really be pretty criminal IMHO. The ceiling was really shot in this particular upstares bedroom chamber and it just needed to come down. Over the years the house had been neglected and had a very leaky roof the ruined the ceiling. The walls are not that bad, but I have decided to leave them and add a second wall that could be removed if needed in the future to completly return the house to original condition. The house does not have any heat in the upstairs so I have added a little foam insulation in this "false wall" . We are tough, but when it is zero outside it get a little too cold for us now days.



lou

Dev Emch
07-18-2005, 2:22 PM
Boy did I start something here...:)

Per, I have worked with blue board and regular drywall. The drywall has to be one of the most horrid things going. You really know your in trouble when you hang spartan artwork on the wall and illuminate with task centric halogen lights. Nothing shows the defects and flaws better. This is esp true for transitions between tape zones and field paper. Even with a PVA type primer, it stinks!

The blue board is a compromise. This board has a special paper that allows the two grades of plaster to stick better. The plaster used with this method will delaminate from regular sheetrock. When you see this material installed, it really looks easy as the pros work the wall. When you try it, you will learn that this is not easy and esp. if your doing ceilings, your neck and back will not be normal for a days! But the result is worthwhile.

Ironically, the blue board finish material actually has a significantly harder finish than drywall mud which is what attracted me to it years ago. Drywall mud is calcium carbonate, latex and water. Sounds more like a heartburn remedy than a wall finish. But that is what everyone uses.

But after seeing the posts by Per and Lou, I think that its time for me to reconsider my drywall completely.

For Lou....

Where did you pick up the knowledge to do lath? Can you give us a quick rundown as to how to do it. Lath, plaster, tips, needed tools, etc. I know that Garrett Hack used lath in his new shop and its totally killer!

I also know that sound reflects differently when you use drywall. You have a tin like response whereas plaster tends to absorb more sound and lower the reflections. I dont know about you guys but it feels more comfortable to have less tinniness and reflections.

lou sansone
07-18-2005, 9:26 PM
hey dev and dino.

my plastering is really geared toward 18th century houses and is not a 3 coat system, like a fine modern house would have. I am trying to simulate or replicate the existing walls in my own home. You can still by wooden lath at some places. I nail it up with about 1/4 gap between each one. I use an air nailer to save my shoulder especially on ceilings. For the style of my home, all the moldings go up on top of the lath and the plaster will butt right next to it.
I use a material called structolite or perliated (sp) gypsum , as far as I know this is modern plaster. I mix it in 50 pound batches with a power mixer to the consistancy of thick mash potatos. That gets dumped out on a 4' foot piece of plywood on a set of saw horses in the center of the room. That is where I will fill up my Hawk. I then use a hawk ? ( 12" square plate with a handle in the center ) and a masons rectangular trowel to spread it out. I usually take a hose and spray down the lath prior to this so it is wet and will not pull all the water out of the plaster too quickly. Just keep spreading it out and pushing it into all the lath cracks to form the keys you will need. To test for thickness above the lath you can take the trowel and sort of scratch a line until you hit the wooden lath. I like to put at least 1/4 to 3/8 on top of the wood.
Since I am looking for that uneven look, I have to delibertly leave some lumps and bumps. If you can get a helper to mix while you spread that is ideal. the stuff have about a 20 minute pot life and then it starts setting up.

It takes several hundred pounds to do a room 15 x 15. you will be mixing all day.

after it is cured in a few days I then white wash it with 2 coats of white wash. the recipe for it has not changed much in 300 years, but I do cheat a little and add pva to give it a little more flexibility. white wash is made by
equal parts of whole milk and white elmers glue. usually 1 gallon of each and then about 10 to 15 pounds of the whitest lime you can find. I have found the "minute man lime from conklyn mass" is the whitest one around. Power mix it up so it has the consistancy of pancake batter. this will keep covered for a few days and then will start to stink. Get some 4" brushes and start painting it on the cured plaster. thick is fine, thicker is better. wait for it to dry and in a day or 2 do it again. 2 coats will look like a million bucks and you have never see such a beautiful wall. it just glows white! A 15 x15 room will probably use 8 to 10 gallons of mix.

enjoy
lou

Dev Emch
07-19-2005, 3:30 AM
Thanks Lou...

My neighbor used structolite to build the interior of his house. But his house is based on new mexico pueblo design repleat with a lateva ceiling and peeled log structures and a hoppi ladder to the second floor. The stuff he got was an older form of structolite or one from new mexico where it is actually a pinkish adobe color. I guess the new stuff that you can buy today has a white color as they changed the mine from where this stuff comes from.

When you say lumpy, how lumpy are your walls? The photo looks like you used veneer board or blue board which is pretty flat.

When you spray down the lath, are you not concerned that your going to get water into the flooring? Clearly you have to tape off and cover with a drop cloth but hosing a room down can get that flooring wet.

When I talked to the plaster dealer today after I saw your photo, he told me that the normal process is to first apply the plaster and then to apply the finish coat which is very thin. The finish coat plaster is called calcoat. Would this do a similar job as the lyme white wash?

If you have ever done veneer plaster you know that it too is a two coat system. You have to learn to to the swirl dance and layer the first coat on at about 1/8 inch thickness and work it. Later you will apply the second coat which is the finish coat and it goes on about 1/16 in or so. At any rate, your never supper perfect and this type of wall still has some "lumpiness". Do you think that your method produces about the same lumpiness as does the veneer process? Just trying to get a feel here.

So far, my experience has been that there is no substitute for real plaster. Your going to have to skim coat and work veneer plaster and that is where the real labor is. Period. Sure I can save a bit on installing blue board in liue of lath or metal lath. But the unpleasant aspect still remains and it sounds like its one of those things where you just have to bite the bullet and do it to get done with it. The sooner your start the sooner you finish. No free meals.

Thanks Lou...

P.S. When did you say that your new program "Lou's Olde House" airs on PBS? :)

Dev Emch
07-19-2005, 3:42 AM
Lou...
One more question. The lath is 1.5 in by 3/8 in thick. Would it be a good idea to just use two cutoffs of lath as spacers when placing the next course? This would make the key slot 3/8 in in place of the 1/4 inch you suggested.

lou sansone
07-19-2005, 12:49 PM
hi dev

to your questions. first of all on the hosing down the lath. I keep the floor really well tarped because the whole process is a big mess, especially the white washing. Second, the walls are sort of lumpy but the photos do not show that. I acually have some blue board installed in one room, but it is much flatter than the lath rooms. I went to lath so I could get that rippled look that only lath will give. Remember this is a very early house and I do have lots of original plaster ( I know it is from a variety of indicators such as hand forged nails and hand split lath, ect) to compare the texture to. I don't put the second coat of the thinner plaster on because in some ways the whitwash does that, but with the the nice drips and sags that you get. Having said that, blue board is not a bad option if you don't want to go to all the trouble of nailing lath. Finally, the gauge idea is a good one.
thanks
lou

Chris Mann
07-19-2005, 6:58 PM
I did some plaster work when I apprenticed a few years ago. We used the metal lathe. First coat is the scratch coat. If I remember correctly it was straight stucolite. After it was trowled on we took a piece of left over metal lathe and raked it all down. The next coat was also straight stucolite, but we applied it with a pool trowel and used a 2x4 to screed it flat. The last coat we mixed 50/50 stucolite and lime and just put a skim coat on to even it all out. The supply place i get plaster from now stocks a finish coat that I've used for skim coating. We also made some curved moldings out of plaster.

The wood molding was applied after the plaster was finished, but we put in blocking that we used as a reference to get the wall relatively flat. I think I can find a few pics...

http://www.mrmann.com/me/misc/2002-%2012.18-%20antique%20shop%20job%20-001-web.jpg

http://www.mrmann.com/me/misc/2002-%2012.18-%20antique%20shop%20job%20-013-web.jpg

lou sansone
07-19-2005, 8:41 PM
excellent work! I agree with the 3 coat method, but for really early houses all you need is 1 heavy coat and a couple thick coats of white wash. thanks for sharing them with us

lou

Dev Emch
07-19-2005, 10:15 PM
Chris...
That is very nice work. I also like how you pulled those curved cove mouldings. That is how you do it. Not that plastic cheese-mo wrap around stuff.

So how thick is each of these three coats? The last coat is a skim coat so I figure its about 1/8 in or so. But how about the scratch coat and the second coat?

When you used the 2x4 to screed the 2 nd coat, did you install some kind of runner along the top and bottom for the screed to run on? If not, now did you know how to maintain a uniform thickness as you went?

I think its pretty clear now that this method is the way to go if you can get away with it. I know that there are fire stop requirements and I dont know how the inspectors will react to lath plaster. We may have to just nail up the fire stop drywall and then lath over it to make them happy.

But this method can be used to obtain a variety of results. Lou used it to mimick the vintage plaster in his 1700s home. Chris posted a photo of what appeared to be a semi formal home. And my neighbor used structolite to mimick the new mexico pueblo adobe style. So it has versatility.

Thanks for the info

Chris Mann
07-19-2005, 10:30 PM
thanks, I'm pretty proud of that. It was back breaking work. Lugging 80lb bags up a few flights of stairs and mixing it all by hand was not exactly fun.

For the plaster walls we added blocking at the top and bottom for the full length that was padded out to the final thickness of the wall. This gave us a reference point to screed off of and also gave us something solid to nail the base and crown to.

We just did the thickness by eye. First coat filled in the metal lathe (or in some cases the brick motar joints) with enough left over to give the second coat something to grab onto, so maybe 3/8". The second coat was fairly close to the final dimension, so probably about 1/4". I'd say the final coat isn't much more than a 1/16th to an 1/8.

That's an old row house in old town alexandria, from the 1800's.

I would think if you used metal lathe and made your plaster walls 3/4" thick, you'd beat any fire codes. It's essentially a cement wall when you're done.

Jason Roehl
07-20-2005, 8:22 PM
Firestops are generally horizontal blocking installed between studs. My house, which is ~1.75 stories, and balloon-framed, has firestops between the first and second floors. Whether or not you have an essentially cement wall, if you have empty wall cavities (redundant?) that run from the basement to the top of the house, you have a huge fire hazard that greatly speeds the engulfment of a house in a fire. In some areas now, code calls for every penetration between floors has to be sealed with a fire-rated caulk or other sealant. This includes all plumbing and wiring.