After each coat, you must allow the all-purpose joint compound to dry fully. Can you put drywall mud over […] Read more: Plaster 101: DIY Repairs, Tools & Techniques Repairing Historic Flat Plaster Walls & Ceilings How to Repair Failing Plaster How to Repair Plaster Cracks How to Repair Textured Plaster Test the condition of the wall first by pushing against it … For the first coating, use setting-type compound. Quick sanded off any peeling paint and leveled previous crack repairs. There are actually three layers of plaster applied to lath to make the complete job. It dries in under an hour in thin applications. The first two are a mortar like stuff that sometimes contained animal hair and is the origin of the term horse hair plaster. A full skim coat, patching, or covering lead paint. For the sake of argument, let's assume you are doing a full skim coat. What I’ve done so far: I’ve scraped and sanded all to get anything loose or cracking off. I am fixing up the plaster walls of a bathroom awant to skim coat it. Repair any water stained surfaces and seal them with primer-sealer before skim coating. Other than this, the ceiling is now reattached and ready for a skim-coat of plaster or a fresh coat of paint. Hi! Repairing Peeling Plaster Top Coat. There were LAYERS of old paint to get off. It may take several coats and extra effort to create a smooth finish or mimic the existing texture. In general, many GP premixed compounds specifically say not to be used as a skim coat. Skim-coating can rescue a wall with numerous hairline cracks but cannot help a wall if the plaster is loose or unsound. This is all normal since we've been building up the base and structure of the plaster with new material, but that's all about to change. The answer really depends on what you are trying to do. It dries without much, if any, shrinkage, even when thickly applied. In thicker applications, the dry time is a few hours. If the paint is peeling or plaster and joint compound are popping off, remove all the loose material, wipe away all dust, and coat with primer-sealer. To finish a typical drywall patch on a plaster surface, perform the following three coats: Embed paper tape over the edges of the drywall patch, coat the paper tape to hide it and apply a thin polish coat after sanding the joint compound smooth with 100-grit sandpaper. For thicker applications, building up the patch through several layers produces better results. Refreshing rental unit bathroom with plaster walls and latex paint. Start with a full bodied joint compound, not a lightweight. Skim-coating is done with drywall compound: a white, pastelike substance that is applied to drywall to cover joints, cracks, and nailheads. Giving Plasters Magic a shot on some of these larger cracks followed by mesh and rolled-on skim coat of joint compound on the walls/ceiling. Up until this point in our plaster repair/skim coating series, the joint compound we've been applying to the walls has felt a whole lot thicker than the term "skim" implies. This patching plaster is smooth and spreadable. Repair the damage as needed and finish the repair with a few skim coats to smooth the surface. Finally, skim-coat over the washers with drywall joint compound. Skim-coating can rescue a wall with numerous hairline cracks but cannot help a wall if the plaster is loose or unsound.