[Username10]

Long story short i patched hardcoat with drywall mud and there’s loosening issues here and there on the outside cold wall.

The house was built in the 30’s and I’m pretty sure it’s a sears catalog home. The wall begins with some kind of tile block which gets covered with a drywall with holes that are designed to grab the brown coat. Then of course the skim coat. Just brick on the outside of the “tile block”.

When we bought the starter home 20 years ago there was drop ceilings and paneling everywhere. The paneling was glued and nailed with construction adhesive which removed the paint down to raw plaster when i removed all the paneling and drop ceiling. I’m guessing the plaster was never primed properly so somewhere along the line the homeowner decided to cover everything with paneling and the drop ceiling.

Muscular of the paint on the outside walls could have just kept peeling so in some areas i would just find a stopping point, oil prime, and here’s the catch, patch with drywall mud. Now I’m thinking i probably should have hired a plasterer. It’s not too too bad but there are areas here and there where apparently I’m guessing the drywall mud doesn’t like the cold wall. There are some bonding issues and paint will stay but if there’s a breach and i go to peel it seems like it could just keep going.

Sinking feeling.

I just hope the plaster god and the next homeowner forgives me.

 

[ClarenceBauer]

If the old paint peels off leaving the smooth White coat of plater showing it may be due to the oil based paint applied before the plaster had cured or it could be a moisture problem. For doing new repairs over the existing plaster I have used Peel Stop with very good results.
As for using a Joint Compound to skim over old plaster the two products do not have a good coefficient & will oppose each other in an area of high moisture.
You will need to use a Lime Based product.
Examples of products that you can use.
Diamond Veneer Plaster.
Uni- Kal.Veneer Plaster
Kal - Kote Veneer Plaster
The above are a Dry mix packaged.
The below are a wet mix.
Variance
Safran may not be available in USA now.
San Marco (does not have a shelf life)
Master of Plaster (will keep as long as it is covered with a little water)
Of all the above Master of Plaster & San Marco are the very best in my opinion. The cost of the wet mixes will be higher.

 

[Biscuits]

Those tile blocks are terra cotta. They were briefly used in the 1930s and are actually structural.

Don't try to nail into them.

When the house was built, the interior was most likely painted with what would be something like calcimine.

Are you using mud that needs to be mixed with water? Or the premixed stuff?

 

[Username10]

Seems any chem set type drywall mud id typically call durock and it’s typically used to fill gaps in the just hung drywall board.

 

[mark sr]

Durock is cement board typically used under tile. Durabond is setting compound and I assume what you were referring to.

 

[Username10]

Yes i figured all setting compounds have lime in them.

And through the years I’ve been using premix mud or setting type for random patching. It’s likely moisture getting through from the outside as the weather side of the house sees more paint failure. It’s not too too bad but that’s where it’s happening. Also, on another subject, some original paint is still on the exterior walls and ceilings and recently i had about a 4x8 total section begging to loosen right down to the original plaster.

 

[ClarenceBauer]

Your problem is moisture it will cause paint to peel off old plaster & leave the smooth plaster exposed.
In the photo I see a large piece of paint that looks like it has curled & is hanging down in the corner this is what happens to painted plaster when the house / room is left for a period of time unconditioned.
It will also happen when the house goes from very moist to hot & dry.
If it has a Calcimine coating as stated above it would be very powdery & rub off like chalk. I don't believe that it is calcimine paint.

 

[Username10]

As for the moisture, I’m hoping it’s just 5 year record rainfall in the southwest Pennsylvania area. We’ve not seen this much rainfall ever supposedly.

As for the curling paint, that’s likely a piece that was not fully scraped. This ceiling started with 1/10 of this area becoming loose paint and i just scraped it until it stopped for the most part. I’ve used peel stop before on exterior problem paint jobs but I’ve been using either oil primer sealer or a latex and trying to make sure it’s soaked into the peeling paint edges.

Something i wanted to point out. The green that you see on the ceiling are pieces of the original finish (not sure if primer or paint) that wouldn’t easily scrape off so i left it and primed, skimmed, sanded.

I’m wondering if primer is recommended prior to the “lime based” plaster.

Also, the original plaster has a soapy feel. I’m curious what that is and if it would affect long term adhesion of primer or plaster.

I feel bad for all these rabbit trails I’ve gone down but a person just begins to wonder if there’s ever a house that’s not a money pit or if things can actually last longer than one homeowner. I get that there’s no such thing as a truly maintenance free home. A guy can dream right?

 

[ClarenceBauer]

As for the moisture, I’m hoping it’s just 5 year record rainfall in the southwest Pennsylvania area. We’ve not seen this much rainfall ever supposedly.

As for the curling paint, that’s likely a piece that was not fully scraped. This ceiling started with 1/10 of this area becoming loose paint and i just scraped it until it stopped for the most part. I’ve used peel stop before on exterior problem paint jobs but I’ve been using either oil primer sealer or a latex and trying to make sure it’s soaked into the peeling paint edges.

Something i wanted to point out. The green that you see on the ceiling are pieces of the original finish (not sure if primer or paint) that wouldn’t easily scrape off so i left it and primed, skimmed, sanded.

I’m wondering if primer is recommended prior to the “lime based” plaster.

Also, the original plaster has a soapy feel. I’m curious what that is and if it would affect long term adhesion of primer or plaster.

I feel bad for all these rabbit trails I’ve gone down but a person just begins to wonder if there’s ever a house that’s not a money pit or if things can actually last longer than one homeowner. I get that there’s no such thing as a truly maintenance free home. A guy can dream right?

"Also the plaster has a soapy feel" Go back to post # 2 When the original plaster was applied if it was not cured properly the high content of Lime & the oil in the paint caused the formation of a surfactant (soap) which will leave slick feeling on the plaster surface. Think back to the time of home made soap Fat (oil) Lime & potash. To get rid of the soapy feeling lets try samples using Vinegar or Denatured Alcohol one of these should remove the surfactant. Also look into the Keim plaster products. Please note all the plaster products are high $$$ compared to the drywall products. As for the use of a drywall setting compound if you can trowel it smooth where it does not require sanding it may work ok over the plaster provided the surface has good absorption?
I would stick with the use of the Master of Plaster Product.
The cost is high but think of it as aged Wine the older the better , same with Lime, aged Lime cost a lot more & works better.

 

[ClarenceBauer]

Another thought on the existing Plaster using a spray bottle spray some water on the exposed plaster. If the water is absorbed by the Plaster it should be ok for a primer with out using the Vinegar or Alcohol.
Also look at using this Keim product FIXATIV it is a Binder , Diluent & Fixing agent.

 

[Biscuits]

Your repair needs to be from that outside wall most likely to keep the moisture and water out.