Joint compound or plaster of paris?
A former owner had wallpapered the ceiling of my bathroom. I’ve scraped it off but in places, the plaster has come off all the way down to the cement. To patch it, should I use joint compound or plaster of paris? Thanks so much for your help.
A former owner had wallpapered the ceiling of my bathroom. I’ve scraped it off but in places, the plaster has come off all the way down to the cement.
To patch it, should I use joint compound or plaster of paris?
Thanks so much for your help.
I just wanted to thank everyone for the helpful comments.
We tried for about four hours to work with plaster. But the stuff would get hard within 3 minutes to the point we couldn’t work with it. We got about 3 square feet done in the four hours and then gave up after nearly pulling our hair out and passing out from exhaustion. I now agree that working with plaster if you are an amateur is extremely difficult.
We ended up using structolite as a base and then skim coating with joint compound. For now, the ceiling looks great. If it doesn’t last, I’m definitely going with a professional next time.
Hi TJR,
My husband is a professional plasterer,and he recommends using only plaster, it will last much longer. If you need help,he’ll be happy to give you an estimate and do the ceiling for you, if you send us a picture perhaps we can better advise on what would be best.
E-mail:willianprates68@hotmail.com
774-955-3804
Good luck.
I sometimes mix some plaster (powder) into joint compound when patching holes etc. Makes it more durable and it dries much quicker.
HI.If lath or masonary is exposed you definitely need to use Structolite like Steve said.If it’s less than 1/4″you can use plaster of paris mixed with compund and water for faster work.You can get ideas for this serching for “dimond Plaster”
windsweptsoftware.com/myhouse/plasterrepair.pdf –
When he said “the plaster has come off all the way down to the cement” and he was talking about his bathroom ceiling, I presume he’s talking about “all the way down to the base coat”. You don’t often find cement in a ceiling in an old house.
Structolite is definitely the way to go if you’ve got exposed lath or masonry but it sounds like he’s lost the scratch and finish coats.
PlasterWeld or some other bonding agent is probably a good idea over old base coat.
Listem to renomandru, he is totally correct… If you are interested in having a contractor look at it you can email me at acrcontracting@optonline.net
Plaster of paris is very difficult to work with for an amateur. Regular joint compound is easy, but not durable. It is good for skim coating on many surfaces, but for deep and wide patching, you may want to use a setting type joint compound that gets almost as hard. You will not find this everywhere, but Durabond makes it with different setting intervals (60 m, 90 min).
Another commonly used approach is to use structolite (available at home depot) as a base and then skim coat with joint compound if you don’t have the plastering skills.
Structolite gets rock hard and is an excellent base for finish work, but if attaching to brick or concrete, you should prewet the base to ensure that the moisture does not draw out of the Structolite too fast.
Lastly, pay attention to the base. If it is chalky or glossy, you will want to ensure adhesion of the base or finish coat. Depending on the situation, a penetrating primer or plasterbond to ensure adhesion may be advisable.
Joint compound is basically just liquefied dust so it shouldn’t be used in applications greater than ~1/8″ thick.
Plaster of paris is easier to work with if you retard the setting with a little white vinegar or milk. Make sure to spray down the repair area with water first so it doesn’t suck the moisture of the plaster.
plaster of paris is hard to work with use base compound and then joint compound to make it smooth…