Tired of this rough plaster or even spicy on the walls of your house and you want to redo everything? Yes but here, how to get rid of it? We investigated for you. Follow the guide !
Remove an exterior plaster
If it is a thick plaster cement (1 to 5 cm in general), use in priority a hammer plus a chisel, or a small jackhammer, and a lot of elbow grease. Indeed, it is then necessary to dig the joints to purify them, sand the stones to give them a smoother appearance, clear the remains of plaster, and finally finish the joints with lime, sand and pigments according to the region in which you you find. In any case, take care not to unseal the stones and treat the joints quickly so that the walls do not get wet with humidity if the weather is bad. Another solution: rent a sandblaster. It is a big job then but the result is worth the effort. Other DIY enthusiasts have chosen to use a compressed air chisel with a compressor. The work is fast and this method has the advantage of not damaging the stones if you put a reducer at the outlet of the compressor (3 bars). Little tip: by passing the plaster with a pressure washer, water seeps into the micro-cracks and this makes your task easier for the next day.
Refine a rough exterior plaster
It is best to use a grinder with a grinding wheel. This makes it possible to level off the ends of the plaster. Warning: work with gloves, a good cartridge mask and protective glasses because you are not protected from a flash in the eye or in the hand.
Remove an interior plaster
Before you start, you need to determine what type of plaster it is. You can soak a small part of it and watch how the surface reacts: - If the plaster is water soluble (plaster fiber): it is easily recognized. The roughness is not aggressive, somewhat drop-shaped. It peels off like wallpaper with a paper stripper, or using water and a painter's knife. Another solution: brush the wall (in 50 x 50 cm squares) with very diluted wallpaper paste (2 to 3 times too much water), wait two minutes and then remove the plaster using a spatula or d 'a painter's knife. - In the case of plastic plaster: its appearance differs but we can always see the direction of spreading because it has been rolled. The roughness is a little flat and not very aggressive for the hands. This plaster is peeled off with a hot air gun and a spatula. - If it is a plaster of the "plaster mortar" type: it must be scraped and then sanded. You can also use a heat gun. - If it is a plaster of the "cement mortar" type: it is of a yellowish or grayish tint, porous and very aggressive. It takes a grinder to get rid of it, or prick it by hand using a small pneumatic hammer before plastering or with a plaster-based coating so as to cover the roughness and plug all the holes. Please note: a large amount of plaster will be required. It is passed with a large float or a plaster smoother.
Remove painted interior plaster
When the plaster has been painted, it is even more difficult to remove because the layers of paint serve to protect the plaster. It is then necessary to scrape the plaster as much as possible using a mason's riflard (a sort of rigid and wide coating knife of about ten centimeters), apply a layer of printing diluted according to the recommendations and carry out a raking to the coating in order to level the walls. But raking is very technical and, without experience, it is very difficult to obtain a smooth and straight wall. Another solution: cover the wall with Placoplâtre® but you lose space in the room. To read : "Works: masonry, plaster, insulation" by Robert Longechal, editions Fleurus. Our practical DIY videos