Plaster Repair

[JasonW]

Thought I'd share a few pictures of the plaster repair I'm doing right now.

First thing I did was to identify the areas of plaster that was loose. I used a product called "Big Wally's Plaster Magic" for the first time. I gotta admit, this stuff works like a charm! The plastic clamps you see here holds the loose plaster in place while it bonds. Takes about 2 days to cure. Then the clamps can be removed.

The last picture shows the slanted section of the ceiling almost done and fiberglass mesh being applied to the upper part of the ceiling before it gets skimmed.

[JasonW]

Here's a better shot of the fiberglass mesh and another of a dormer in another room that I'm working on.

[naptownCr]

does the mesh cover the entire surface?
what do you skim with?

[JasonW]

Yes, it covers everything. For this job, I'm using a gypsum based plaster. The larger repairs on the original plaster was done with a lime base plaster.

[naptownCr]

What's the difference is the gypsum just drywall mud?

[JasonW]

Yup, that's it. I like the green top for this work because it has the right consistency to lay it on thick. It takes 2 coats to cover the mesh and then just a touch up after that.

The husband wanted to keep the plaster; the wife wanted sheetrock over it. I made this suggestion so they could both get what they wanted. Plaster is saved, and she gets a new ceiling. :)

[naptownCr]

What about adding gauging plaster to the mix. Then it could be polished down to an almost original finish.

[JasonW]

Never tried that. Will it do anything to the setting time? This will also be painted when done.

Add: I'm not finding any suggestions to add guaging plaster to drywall mud. I'm only finding the lime putty/sand mix.

[naptownCr]

Old drywall trick
Put a bunch of mud on a scrap piece of drywall. make a moat or a dam with the center empty. pour in some water and add slowly some gauging plaster. when the plaster starts to thicken mix the whole thing together. Now you will only have about 10 minutes to get this on the surface. It will set up rapidly and can be troweled off with a squirt bottle to a glass smooth finish.

[nEighter]

Jason, I have been eyeing a graco Mark V for a couple years now. I WILL OWN ONE SOON. here is a video. Can you imagine if you had one, how much time you would save?

http://www.youtube.com/watch?v=vnVIRHS2NHs

[naptownCr]

Jason, I have been eyeing a graco Mark V for a couple years now. I WILL OWN ONE SOON. here is a video. Can you imagine if you had one, how much time you would save?

http://www.youtube.com/watch?v=vnVIRHS2NHs

Please invite me to the bankrupt auction when you have to sell all the shiz you bought. I smell some deals

[nEighter]

?? want is not the same as get..

[JasonW]

Cool machine but I don't do a lot of this work and it only took me about 3 hours to cover 400 sf with the fiber mesh and put the first coat on. It would take me 10 years before that thing paid for itself. Most plaster repair I do don't call for full coverage either.

This room had a lot of issues...

[nEighter]

For remodel jobs where there is hacked up walls though.. could be good. Workaholic showed me one on ebay a couple years back that was going for about $1200.00.. so deals are out there.. hell even if you needed to put it through a rehab.. it would still save you a ton of money.

[ParamountPaint]

I'm almost finished with a plaster job, too. Mine all came off down to the basecoat and some went down to the wood lath. You can polish regular durabond like plaster, but you gotta be on the ball. I used USG Structolite to replace the basecoat over wood lath. I did both scratch and finish with durabond 90, although I was too slow from time to time and had to skim a few areas with easy sand. I'll get some pics up soon.

[DavidC]

Pretty cool technique (OP) you got going on. Don't forget the finished pics.

good Luck
Dave

[Paint and Hammer]

I've never seen that before. (full mesh on ceiling)

Teach me something here:

What is the advantage of putting another layer of plaster as you are doing over putting up drywall?

Those plastic disks seem to stand quite high or is it the pic. A Canadian store (Lee Valley I would post a link, but I'm not at 15 posts) sells metal ones that are quite flat when in place. They don't have the diameter of those though.

My shoulder hurts just looking at that ceiling. :grin:

[JasonW]

I've never seen that before. (full mesh on ceiling)

Teach me something here:

What is the advantage of putting another layer of plaster as you are doing over putting up drywall?

Those plastic disks seem to stand quite high or is it the pic. A Canadian store (Lee Valley I would post a link, but I'm not at 15 posts) sells metal ones that are quite flat when in place. They don't have the diameter of those though.

My shoulder hurts just looking at that ceiling. :grin:

The advantages of doing this are many. The first is it preserves the original plaster ceiling. Dry wall would ruin it for ever with all those screws going through it. Not to mention all the probing you need to do to make sure you've found the joists. The second and third would be time and money. It will take me a total 15 hours to re-coat the ceiling this way. The fourth is less mess. No cut offs to deal with from sheetrock, less waste. Also, no flat taping to the walls.

The disks you see are clamps that come out after the plaster repair has set up. The third pic in my first post is a completed repair, ready to be covered. This plaster repair system replaces the old metal washer method that's been used for years. It was invented by Rory Brennan, the plaster expert on this old house.

I wouldn't recommend using the fiber mesh on every repair job, only the most extreme cases. This room had a lot of cracks and bad repairs done over the last 100 years. At some point, a bathroom was added off of this room and I suspect the introduction of hot, moist air from the un-vented shower caused most of this to happen. By first stabilizing the old plaster, then covering it with fiber mesh and conventional joint compound, should give a more forgiving and flexible top coat while keeping the harder surface isolated on the back side of the mesh. If you don't stabilize the old plaster first then it won't be long before those cracks come through the new top coat and you start getting calls from an upset customer.

[Paint and Hammer]

Thanks Jason....I just wrote a long response, but when I hit "submit" it booted me out....arg!

The short of it is I can see where you are coming from.

Haven't been here that long so take my comments as inquisitive not argumentative.

Interesting about the anchors...do you have a link? Big fan of TOH.

If the customer wants to preserve it than of course thats the way to go. (Personally l've never had a customer ask for preservation)

I've owned 3, 80-100 year homes and have done a 'fair' amount of repairs and repaints after the electricians and plumbers have 'had-their-way' with the house.

Where I see most of the cracking is larger rooms where there is joist sag over the years. The worst being in the middle of the room.

The other, above doors. I can't help but feel drywall is a better longer lasting solution to these.

BUT....I do not have experience with applying plaster, just conventional drywall and mud.

[JasonW]

Here's the link for Big Wally's Plaster Magic (http://www.plastermagic.com/4-simple-tips-for-plaster-patching). He also has a plaster repair mix that I use for patching. You'll find everything you need to know at that site.

Sagging ceilings would be another good reason to go this route instead of adding even more weight from another layer of sheetrock. I would be concerned about the long term affect of adding another 300 pounds for cosmetic reasons.

[Paint and Hammer]

Thanks for the link. I'm going to do some reading there.

Your right about the extra 300lbs...to be honest I'm still on the fence about it. I think both sides have valid points.

[ParamountPaint]

Plaster is a superior finish that is only eschewed today because of the cost. It combines sound dampening, fire resistance, mold resistance and impact resistance. It even has an effective R-value. There are plaster walls that are hundreds of years old.

There is no valid point to laminating with drywall, besides economic reasons.

[Paint and Hammer]

I've been mulling this over today.

I realize that I am behind the 8 ball by suggesting introducing drywall to plaster.

Paramount you say plaster has lasted a 100 years. For sure. I think what might be considered is location.

Here, our city is on the flood plain of a river. Houses are constantly moving. The only structures that I've seen that the plaster hasn't deteriorated are big brick (limestone) and mortar buildings like our legislature.

Could it be the extreme hot/cold cycle of our climate?

Plaster does not seem to hold up here.

These pics are VERY common. Complete spider cracking throughout the house. The plaster is loosely adhered to the lathe. Would you suggest replastering this?

I'm not talking money, I want to know about long term durability. To me plaster doesn't have strength in itself, it needs a solid substrate. I've seen many houses where its seems to almost have crumbled to dust.

Are you dealing with the same issues?

http://i913.photobucket.com/albums/ac331/paulspaddle/IMG_7109.jpg

http://i913.photobucket.com/albums/ac331/paulspaddle/IMG_7112.jpg

[ParamountPaint]

Is that over wood, metal, or gypsum (rock) lathe? How old is it?

That looks like the joists are telegraphing. If it was like that as long as you have known, maybe it was a poor job to begin with. I don't get too excited about spider-webbing, as you can generally vee it out and fill and it will probably be good for another 50 years.

There are two major reasons for plaster failure: water and movement. Water will de-laminate the finish coat Movement is trickier...usually cracks will appear around doors, windows, or corners as a symptom of the "weakest link". Often, these are one-off cracks and once repaired, will remain solid. If you do indeed have a lot of structural movement, I suspect you won't fair any better with drywall.

I bet that if you vee'd out those cracks, applied a bonding agent, and went over it all with a veneer plaster, you would have a long lasting repair. If you don't want to use plaster proper, you could use a setting compound (try national gypsum's pro form HS). You just have to be quicker on the double back with setting compounds.

Plaster is more than meets the eye and as much as I do, I have only scratched the surface of the art. If done properly, you will have zero dust and be finished with one room in hours, not days.

[Dusty]

I see a mixture of here. In some homes the plaster has held up quite well in others, not so well.

It's a judgement call.

Removing plaster is a horrible job and I will avoid it if I can. Oh yea. I see many advantages to the method Jason introduced. Have not read through the site yet, but it is bookmarked for sure.

[Paint and Hammer]

Is that over wood, metal, or gypsum (rock) lathe? How old is it?

That looks like the joists are telegraphing. If it was like that as long as you have known, maybe it was a poor job to begin with. I don't get too excited about spider-webbing, as you can generally vee it out and fill and it will probably be good for another 50 years.

There are two major reasons for plaster failure: water and movement. Water will de-laminate the finish coat Movement is trickier...usually cracks will appear around doors, windows, or corners as a symptom of the "weakest link". Often, these are one-off cracks and once repaired, will remain solid. If you do indeed have a lot of structural movement, I suspect you won't fair any better with drywall.

I bet that if you vee'd out those cracks, applied a bonding agent, and went over it all with a veneer plaster, you would have a long lasting repair. If you don't want to use plaster proper, you could use a setting compound (try national gypsum's pro form HS). You just have to be quicker on the double back with setting compounds.

Plaster is more than meets the eye and as much as I do, I have only scratched the surface of the art. If done properly, you will have zero dust and be finished with one room in hours, not days.

ok....got the kids to bed...

Age - 90 years old.
Over wood.

By telegraphing are you suggesting moisture issue? Potentially for one of those that could be an issue as it's upstairs and there wasn't insulation in the attic above for 89 of those 90 years. Who knows....maybe condensation over decades?

The first pic is mainfloor. I believe its from joist sag. You can't see it well in the pic, but it clearly gets worse by the middle.

True about the comment of judgement call. Its hard to make a blanket statement on anything when it comes to this stuff. I think some cracks are "one offs" I also see a lot expansion and contraction through the year. So many things come into play right? How's the overall seal of the house? Where are the moisture areas (kitchens, bathrooms) in relation to the cracks? Central air, steam, hot water heat etc. One pic...one room doesn't tell an entire story.

I think for the second pic, I'll try your advise. You say, "bonding agent"...is there a need to seal it first? An oil base primer, then bonding agent?

I can drywall with pretty much zero dust...this could be a new horizon of challenge.

Thanks.

[Paint and Hammer]

Sorry about highjacking your thread Jason...

[JasonW]

Sorry about highjacking your thread Jason...

No worries, the threads about repairing plaster, not about just my project I'm glad to see some interest in it.

We have a download section with a lot of info on repairing Historical materials. This is a link to Preservation Brief #21, Restoring Flat Plaster. It gives you a lot of different techniques and history on the subject.
http://www.remodelcrazy.com/forum/downloads.php?do=file&id=34

[ParamountPaint]

Bonding agent: Plasterweld (http://www.larsenproducts.com/plasterweld.php)

Double check the integrity of the paint before you apply. I usually use plaster washers across the ceiling before applying the plaster weld. Then, top coat it all. I had a thread here somewhere with a bunch of pics.

edit: http://www.remodelcrazy.com/forum/showthread.php?t=4908&highlight=church

There are a bunch of pics and a link to an album with all sorts of them. That plasterweld is the pink stuff that you can see in some of the pics.

[ParamountPaint]

Here was another post that shows more of what I'm talking about: Plaster Magic (http://www.remodelcrazy.com/forum/showthread.php?t=6123&highlight=plaster+magic).

I've never used the plaster magic, but I have cobbled together my own system that seems effective.

[JasonW]

A couple finished pictures of the "new" ceiling.

[ParamountPaint]

Is that the same wallpaper or did you have to get it replaced, too?

Looks good!

[JasonW]

Thanks. Same paper. That's the other advantage of this technique. You don't have to remove wall paper or even trim.

[Paint and Hammer]

Looks great Jason.

A bit of a daft question here...."How is working with plaster (in this situation) different than a skim coat of mud"?

I'm not a pro (I would label "pro" to someone who does it daily as 'pro'fession) at mudding), not necessarily a skill level.....but I've done a fair amount.

I've never worked with plaster, but am willing to give it a try on a bedroom on my own house.

Things are a bit nutty lately don't have as much time to hang and read on a forum as I'd like.

[DavidC]

Damn, that's nice work Jason. Must have missed it when you posted it earlier.

Good Luck
Dave

[JasonW]

Thanks Dave. The customer gave me a great review on my thumbtak listing too! http://thumb.tk/2E7H It's way down at the bottom... :(

P&H, This is a skim coat of mud. It's just done over the top of stabilized and repaired plaster and an isolation fabric between the two. You need to stabilize first or any attempt you choose to cover it will fail.