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Need lots of help with plaster walls!

We have removed layers upon layers of wallpaper from 4 rooms in our 1860's Maine farmhouse. Most of the walls are horsehair plaster and a few are old drywall. We want to paint them all so that they are uniform.

My first question is for the plaster walls-- There are a few areas that have chipped off/cracked and there are some large holes with the wood backing showing through (all in good condition). I know how to patch everything but what specifically should I be buying to fill holes, patch, skim, etc? Do I need a bonding agent? Are there brands or types that you would recommend and is it likely to be found at Home Depot or a local hardware store?

Second question is-- Paint. What type of paint should I get, can I just use a Kilz primer and latex paint or is there a special kind to get? I'd like it to be the same for the drywall walls so that they match.

Has anyone heard of an insulating paint to use for plaster walls? Would you recommend it?


Re: Need lots of help with plaster walls!

I would personally use "Plaster of Paris" and have... It's fun to work with too... I also used Drywall mud and mixed in a little plaster of paris and a lil water and it worked great..

I have a Guest House too and it worked fine...

I just painted it with a water based paint that I tinted myself..

good luck..

Re: Need lots of help with plaster walls!

Bonding agent for the big holes. Paint the edges and lathe boards with the bonding agent. Use gypsum plaster for the big holes. Slick it off with something straight and firm (I use a piece of cedar siding. Dont go over 4'on the sding) it should be a little bigger than the hole. Pack the hole and slick off(depending on size) When that sets skim with a finish coat of plaster or use sandable setting type joint compound(durabond,sheetrock) and you can use the durabond on chips and small holes. Hope this helps. Any questions just ask or pm me.


Re: Need lots of help with plaster walls!

I'm not sure what warcraft gold has to do with plaster repair so I'm going to ignore that piece of the thread.

For technique for filling in the holes I would agree with plastrr385. I would suggest a couple of cavates to that approach. Prior to doing any in-filling of holes I would stablize the existing plaster with the plaster repair adhesive http://www.pbs.org/thisoldhouse/home/ www.plastermagic.com. Around holes glue every lath, for cracks glue every other lath. The key to longevity with plaster repair is stabilizing the plaster, once the existing plaster is stable the rest of the repair is cosmetic. This method uses the wood lath within the plaster wall to bridge the cracks or holes making fiber tape or application of anything to the surface (superficial repair) unnecessary and additional work. The reinforcement is being done within the wall instead of on top of the plaster surface.

After the existing plaster is stable the in-fill is next. Instead of using a PVA bonding agent, which I consider unnecessary, try adding one quart of isopropanol to 5 gallons of water and using that to wet down the wood lath. The resulting bond of plaster to lath will be mechanical and far superior to any bonding agent. The track record of mechanical bonding compared to using bonding agents writes the complete story. Over a history spanning thousands of years of plastering, bonding agents (being in use for only decades) have proven redundant.

Softening the modern gypsum [structo-lite] (which is designed for modern buildings not old buildings) with lime rather than using an unmodified gypsum basecoat will give the added benefits of being more compatible with the old plaster plus it will set in an hour or so. Apply the basecoat and let it set for a couple of days. This will allow the plaster to crack out over the lath lines. Application of additional layers of plaster will not have the cracks telegraph through to the surface.

Hope these ideas help...PM

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