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Horse Hair Plaster

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14K views 28 replies 8 participants last post by  Masters Tile & Paint  
#1 ·
Got a call from a HO that wants a couple ceilings painted and repaired which are horse hair plaster. Are there any special considerations for horse hair--is oil better than latex for primer? Any issues with patching? Will I have any issues with Durabond or Easy Sand?

Thanks.
 
#2 ·
as long as the plaster is still tight to the lath and is not all crumbly and "punky", you can paint and repair in "normal" fashion.

That said, I am assuming you have experience with the bane of painters - calcimine.

And by experience, knowing how to test and how fast to run when you see it.
 
#3 ·
daArch;482439 That said said:
I only know of it, have never dealt with it. Have been told stories of latex paint falling off onto a sleeping couple that had painted it with a latex paint.

I found this, "The first step is to determine for sure that you are dealing with a calcimine problem, and what has been coated over it. Because it is essentially chalk, calcimine can easily be detected by rubbing a damp finger (sure, spit works) or a sponge on the surface and looking for a chalky residue. Just like if you wet your finger and rubbed a dirty chalkboard, imagine the way the chalk would look and feel on your finger."

Is this an good way to test for calcimine?
 
#4 ·
Yes, essentially.

and if it IS calcimine either on surface or under a layer of paint, then you know what to do.

Many will advise solutions, and some actually work for a few years. I finally gave up on all the guaranteed methods and started overlaying with 3/8 sheetrock.
 
#7 ·
Thanks DaArch.
Last question before I see the job on Friday. If it is latex paint over calcimine, I am assuming that I would have to take off all of the latex paint before I used something like BM's Super Spec Alkyd Calcimine Recoater? I have never had to paint oil over latex, and have always been informed that latex of oil, but not oil over latex. Not sure if this is misinformation (I try to avoid oil unless necessary so have never had a reason to question this information), or if it is not, if it would apply to paints designed to go over calcimine. Plus I am assuming if the issue is the latex is not adhering the the calcimine paint, that adding the extra weight of another later, or two, of paint will only make the situation worse. This is a temp fix, but I certainly would not want more paint falling off hours after I finish the job.
 
#8 · (Edited)
Pete,

First, my condolences to you and your first responder brothers for the tragedy in Boston today. I am sure the fire fighting brotherhood mourns deeply tonight

------

Notwithstanding that technology has changed since I stepped away from the brush, I never heard oil over latex was danger, to the contrary, it was the poor latexes of the 70's that could not be applied successfully over oils.

Now if there is latex over calcimine, it will be coming off in sheets with a chalky residue on the backside - sometimes more than just a residue.

Even if you removed all flaking paint, it would be tenuous to apply another coat of anything over what latex remains.

Latex painted over calcimine that is peeling is a total crap shoot if you can't remove it all and wash the calcimine off.

This is why I said RUN.

IMO, if you can't do a thorough job, it isn't worth doing anything.

again, this is why I overlay without even attempting any remediation.

Let's hope you do not find calcimine as the root cause.
 
#9 ·
If the existing coating is tight adhering and shows no failure you can repaint with latex. If Calcamine is or was present latex paint would have failed. Calcamine burns latex paint because of its high pH. Moor white primer is excellent for old horse hair even though it's exterior. 306 Benjamin Moore Calcamine Recoater works very well too.
 
#12 ·
We've had calcimine cause failure in situations where the existing coating is seemingly well adhered. Under multiple layers of oil-based paint, for instance. The calcimine remains the weak link, and the additional coat of paint is the last straw, to mix my metaphors.

From what I've read, the issue with latex failure over calcimine isn't pH, but rather the water in the paint dissolving the calcimine. I think this is evidenced by the rapid failure when latex is applied directly over calcamine. After all, aren't latexes are more alkali resistant than oils/alkyds? In another thread, far away, daArch mentioned them tolerating pH up to at least 10.

Here's some background information on calcimine, ultimately from OHJ:

http://www.plasterlord.com/notebook/fcalcimine.htm
 
#10 ·
From the sounds of it, if it's calacimine, I would offer the client 2 options:

1. Overlay with drywall now. It will provide the best value, a finished ceiling that should last for decades at a cost comparable to treating the calcamine, repainting, and the risk of future failure.
2. Find another contractor.

The other members are right. Calcamine is no joke and unless you've got a client with deep deep pockets and plaster that is otherwise sound RUN AWAY IMMEDIATELY.

Option 3 (not recommended) would be to offer to do the project T & M and offer no guarantee of quality. But hey, who wants to put their name on a job like that?

In the end, you'll probably just have to learn for youself, like the rest of us.
:censored: the fools that paint over calcamine!
 
#11 ·
Monstertruck;482677 1. Overlay with drywall now. It will provide the best value said:
This is what the Landlord intends, but from what I got from him is that he has a tenant that is complaining about chipping paint and cracks. So, Whatever I do is temporary until he can get her out of their and then he intends on updating the entire apartment. I wanted some info so that if I do encounter calcimine I can tell him what really needs to be done, even if it is only a temporary fix.
 
#13 ·
DAMN that's a good article. That should be a sticky. Would save a lot of band width.

If only that were available when we all learned about calcimine by experience.

(my body twitched as I read that reminding it what I have put it through)

Thanks Gough :thumbup:
 
#21 · (Edited)
Saw the ceiling today--was not calcimine. However one of the worst looking popcorn ceilings that I ever seen. Several spots were big chucks of the texture was coming off. I recommended that he get someone to cover it with blue board. Well, at least now I know what to look for next time I run into peeling ceiling paint.
 
#26 ·
The ceiling had many more issues than just failing popcorn. Looked like it may have been poorly repaired many times, very uneven...I had no idea what it would look like underneath the popcorn. And it was the landlords intent to cover it after he got the tenant out. Plus, it was only a few spots that the popcorn was actually failing in other spots is seemed fairly solid, and although the texture looked terrible.