plaster walls...HELP!!
What advise can be given to an older house with plastered walls? Should I just paint over it? sand down? Can I put sheet rock over it? PLEASE HELP!
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As long as plaster is in decent shape, patch and paint it. If plaster is loose, meaning the plaster that mushrooms out behind the lathe has broken off, then it can be a big job. As Steve mentioned, you have base and trim to deal with. If you want to save the old trim, you generally need to strip walls and fir out studs so that once rock goes on it is at same finished level as plaster was. Its door and window trim that keeps you from being able to just go over top with rock or mounting it directly to studs.
The trick to patching cracks in plaster is to key them. You cut out the crack so that the crack is wider in the back than it is at the surface. Then, prefill the crack with hot mud. Silverset 20 is what I use as it sets rock hard. Fixall works too. Then mesh tape and float. If you take the time to prep cracks properly, patchwork holds up great. I like the character of plaster walls so saved them whenever possible.
What is the issue you have?
Plaster is a great wall surface, it is actually "higher end" and damage resistant since it is hard as concrete, the reason no one uses it anymore is because it is more expensive to install and harder to patch. So if the walls are in good shape just paint and you're good to go.
You can put sheetrock over it if the wall section is really cracked; the cracks in plaster can be a pain to fix, and they tend to reappear. But if you try to put on a sheetrock veneer, you do realize the trim and baseboards will have to come off first and be re-installed, otherwise you will have some strange looking areas where those meet the new sheetrock.
As long as plaster is in decent shape, patch and paint it. If plaster is loose, meaning the plaster that mushrooms out behind the lathe has broken off, then it can be a big job. As Steve mentioned, you have base and trim to deal with. If you want to save the old trim, you generally need to strip walls and fir out studs so that once rock goes on it is at same finished level as plaster was. Its door and window trim that keeps you from being able to just go over top with rock or mounting it directly to studs.
The trick to patching cracks in plaster is to key them. You cut out the crack so that the crack is wider in the back than it is at the surface. Then, prefill the crack with hot mud. Silverset 20 is what I use as it sets rock hard. Fixall works too. Then mesh tape and float. If you take the time to prep cracks properly, patchwork holds up great. I like the character of plaster walls so saved them whenever possible.
You can also use plaster washers (specialty item in our area, look on line) to hold down loose areas that are in otherwise good condition. Plaster of Paris (takes a little practice) for the deep areas, finish plaster for the top, both dry fast and sand smooth, you're on your way. Larger areas, ie. multiple feet square, backfill with 1/4 inch drywall then fill cracks and bring to grade with P of P or patching plaster. You can fix easily and it's so beautiful and durable.
Exactly...you need to dig out the cracks...to many contractors will just try to patch without digging it out first and it just cracks again in a few weeks/months.
Also, if you have to repairs large areas (or several areas around the house) it's often cheaper and easier to just texture all the walls after repairs rather than trying to get all the patches smooth.
I recently discovered plaster washers and was really surprised at how well they worked. I couldn't find them anywhere in St. Louis but was able to order them on Amazon.
If the property is a rental, I wouldn't worry too much about the walls not having the perfect drywall look. It always catches my eye but I've never had a tenant that has complained or even mentioned the walls.
I just rehabbed a rental from 1926 and it still had plaster walls. There were some holes where the previous occupant used too-large screws, and I just used regular joint compound. Sanded it a little when dry, then painted over it. You can hardly tell the hole was there unless you knew where to look and were looking right at it. For a rental that's fine.
I've only dealt with plaster for years and years - kinda can't wait for a house that's only drywall! I agree, plaster washers are great. Another thing that'll help when the plaster has separated from the lathe is to drill a few holes and reattach the plaster with an adhesive - Big Wally's Plaster Magic is one example. This takes a while and can be pricy, but if you're working in a high-end historic house it can work wonders.
If you're a true glutton for punishment and have a wall that has significant cracking and problems, you can order 3' wide adhesive fiberglass mesh, apply it, and skim coat the whole shebang. There are various youtube videos out there that show how to do it.
Another trick I've used on a wall in need of a great deal of help was to just put up a plain paintable wall paper (sometimes it's called "wall liner"). This won't work if there's significant damage, but it worked very well for myriad cracks and crazed areas.
Good luck!
You can go over it w drywall, use longer screws and make sure your hitting the studs.
I'm remodeling my duplex right now - 1890! So it's all plaster. Advice above is sound for sure - there's definitely disagreement online with it comes to materials (hot mud vs fix it all vs traditional lime plaster, etc. etc.). I came to the conclusion that it really only matters if you're doing historic preservation or something of that nature (then go with traditional methods)... Personally, I'm kind of in the middle...
DAP makes a product in 25 pound bags called Plaster Wall Patch (DON'T use true plaster of paris for big reparis because the working time is too short - like 5 min). It is more like a traditional mix, but is easier to work with (mixed like joint compound, but can be applied thicker).
Regarding the repair process, @Ben Skove mentioned Big Wally's Plaster Magic - they are crazy expensive, but their videos are great! Very informative for how-to. For loose sections that need to be secured, I used their process (plaster washers, etc.) but used liquid nails instead. I also skipped the plastic washers and just used fender washers backed with pre-drilled pieces of wood (lath scraps). Worked great! Just be careful while screwing them down since they don't give like the plastic washers.
Also, I haven't tested the difference, but I use a plaster bonding agent (lots of different brands, just read labels to make sure it works for plaster) where I'll be applying new plaster to old.
Oh, and it's best to get carbide/masonry blades/scrapers/bits etc. since plaster will eat through your common steel implements CRAZY fast.
Good luck with your projects!
@Maher Bateh Several good tips above. But one caveat. Understand that plaster walls will invariably have lead paint. Know and understand the laws and requirements, and make sure you don't create a nightmare for yourself.
Ok, Lots of good tips here and hopefully you can use some of them but if it is not just screw holes and smaller repairs and you need to do a whole skim coat pay someone to do it. This is one job where it pays to get someone in. It will be expensive but you can either do this well or you can't and large jobs take a lot of time for an inexperienced person even if you can do it. Time better spent doing a lot of other things. That being said if its a rental, it doesn't have to be perfect and certainly sheetrocking over a bad wall is also an option. I had one apartment done completely because it was so bad when I took down the wallpaper. The rest were patches we could do but this one where there were whole sections of wall falling off I don't think I could do what those guys did in 4 days if I had a month.
1926 ... I thought you didn't do pre-war properties? Did it have a fireplace as well?
Aye, but just where are the studs in an old Victorian, balloon framed building ;)
Personally, I am not a fan of sheetrock over lath-n-plaster.
If the plaster is in descent shape and we have no need to get into the wall cavity (i.e. not an external wall with wind blocks which need to be removed so we can insulate) we will endeavour to repair and leave the plaster ... as others have mentioned, it stands up much better than drywall.
If the plaster has pulled away from the lath, we will typically remove it, level the plane of the "studs" and sheet rock the wall. To redo the wall with plaster is far to time consuming and costly at today's labour rates ... not to mention the difficulty in securing enough horse hair ;-)