The definition and function of plastering
Refers to the use of lime mortar, mixed mortar, cement mortar, polymer cement mortar, etc. on the surface of a building (such as brick walls, concrete reduced Apply a layer of material about 20mm thick on the surface of a force wall or beam or column to make the surface of the building smooth and easy for paving or dusting. It also plays a role in protecting the wall or column, as well as waterproofing, heat insulation, and sound insulation.
Materials and construction techniques required for construction
1. Materials required for construction
Cement, sand, water
2. Plastering construction technology
1. Process flow
Clean the base, water and moisten it, lift it vertically, square it, find the rules, plaster the cake, apply cement skirting or dado - make corner guards and apply cement window sill - fill the wall with ribs - apply primer - Repair reserved holes, electrical box slots, boxes, etc. - Apply dust
2. Operation process
(1) Base cleaning
1) Brick masonry: Surface debris, residual mortar, tongue ash, dust, etc. should be removed.
2) Concrete matrix: Chisele the surface or spray 1:1 cement mortar on the surface after moistening it (add an appropriate amount of adhesive or interface agent
3) Aerated concrete matrix: The interface agent should be applied after it is wet, and cement mixed mortar with a strength no greater than M5 should be applied at the same time.
(2) Water and moisten
Generally, the day before plastering, use a hose or rubber tube or watering can to water the wall from top to bottom to moisten it. It is advisable to water twice a day. .
(3) Hang vertically, set squares, find rules, and make gray cakes
According to the plastering quality required by the design drawings and the flatness and verticality of the base surface, use a wall as a benchmark , hang it vertically, set it squarely, find the rules, and determine the thickness of the plaster. The thickness of the plaster should not be less than 7mm. When the wall has a large concavity, it should be lined in layers. The thickness of each layer shall not be greater than 7~9mm. During operation, the ash cake should be applied first and then the ash cake should be wiped off. When plastering the cake, you should determine the correct position of the cake according to the indoor plastering requirements, and then use the ruler board to find the vertical and flat position. The gray cake should be plastered into a 5cm square shape with 1:3 cement mortar.
When the room is large, you should first pop up the cross center line on the ground, then pop up the corner line according to the flatness of the base layer, then hang the vertical line 100mm away from the inner corner of the wall and pop up the plumb line, and then press The corner line that pops up on the ground is turned to the wall, and the wall plaster layer thickness control lines on the two walls in the inner corner are popped up to make a gray cake, and then the ribs are filled according to the gray cake.
(4) Apply cement skirting (or dado)
Fill the ribs according to the plastered ash cake (the ribs can be made wider, 8 to 10cm is appropriate, so The ribs are the basis for plastering the skirting or dado, and are also used as the basis for plastering the wall). Apply 1:3 cement mortar to the bottom layer. After plastering, use a large bar to smooth it. Rub the wooden trowel and use 1:3 cement mortar at room temperature the next day. : 2.5 The surface layer should be plastered with cement mortar and calendered. The thickness of the skirting or dado should meet the design requirements. If there are no design requirements, it is appropriate to protrude 5~7mm from the wall. The l51 on the skirting or dado protruding from the plastered wall must be smooth and straight. After the skirting or wall is plastered, stick the ruler on the large surface to be level with the upper lip, and then use a small trowel to flatten the upper Vl. Light, the edges protruding from the wall should be made into obtuse angles, and no stubble or flying edges should appear.
(5) Make corner protectors
The sun corners between walls and columns should be protected with 1:2 cement mortar before plastering the walls and columns. The height of the corner protectors should be from the ground. 2m above. See Figure 1.1.6.2 for details. Then water the sunny corners of the walls and columns to moisten them. The first step is to set up a figure-eight ruler on the front of the sun corner. The ruler protrudes from the side of the sun corner, and the thickness of the protrusion is equal to the plastering surface. Then apply cement mortar on the side of the sun corner, rely on the edge of the ruler, and smooth it with an iron trowel. Remove the excess cement mortar according to the width of the corner guard (not less than 5cm). In the second step, after the cement mortar is slightly dry, move the splayed ruler to the plastered corner protector (the splayed slope faces outward). On the front of the sun corner, apply cement mortar on the edge of the ruler and smooth it with an iron trowel. Remove the excess cement mortar according to the width of the corner guard. After wiping, remove the splayed ruler, paint the sharp corners of the corner protector with plain cement slurry, and use a corner squeegee to stroke it from top to bottom to form an obtuse angle.
(6) Plaster the cement window sill
First clean the base of the window sill and re-pare the loose bricks. Score the brick joints deeply, moisten them with water, and then pave them with 1:2:3 pisolite concrete. The thickness should be greater than 2. , apply adhesive plain cement once the next day, and then apply 1:2.5 cement mortar surface layer. After the surface reaches initial setting, water and cure for 2 to 3 days. The plastering at the bottom of the window sill plate should be straight and without burrs.
(7) Filling the wall with ribs
When the ash cake mortar reaches 70 to 80% dry, the same mortar as the plaster layer can be used to fill the ribs. The number of ribs should be based on the room. The width and height are determined, and the general standard bar width is. The distance between two ribs should not be greater than 1. . When the wall height is less than 3. It’s a good time to do muscle-stretching exercises. Greater than 3. It is advisable to make horizontal bars when making transverse punching bars, and the distance between gray cakes when making transverse punching bars should not be greater than.
(8) Apply primer
Under normal circumstances, it is appropriate to start applying primer about 2 hours after the rib filling is completed. Before applying, a thin layer of dust should be applied first. It is required to apply primer on the base body. Strictly, apply forcefully to squeeze the mortar into the small gaps when applying, then install the mortar in layers, apply and fill the ribs, use a wooden pole to scrape it smooth, and use a wooden trowel to rub the hair.
Then comprehensively check whether the base ash is flat, whether the inner and outer corners are straight and clean, whether the intersection between the pipe and the inner corner and the wall top plate are smooth, flat and straight, and use a support board to check the verticality and flatness of the wall. The plastering on the wall behind the radiator should be done before the radiator is installed. The plastering surface should be connected smoothly. The baseboards or dado skirts on the floor and behind the pipes should be cleaned in time to ensure that they are completely clean.
(9) Repair reserved holes, distribution boxes, slots, and boxes
After the base plaster is smoothed, a designated person must immediately remove the reserved holes, distribution boxes, and boxes. Scrape off and clean the wide lime sand around the trough and box. Use a large brush to moisten the perimeter with water. Then use 1:1:4 cement mixed mortar to smooth the surrounding of the hole, box, trough and box. smooth.
(10) Apply the overlay ash
You should start applying the overlay ash when the bottom ash is 60 to 70% dry (if the bottom ash is too dry during wiping, water should be moistened). The thickness of the surface ash will be about 100% after two passes. It is best for two people to cooperate at the same time during the operation. One person will scrape the thin ash first, and the other will smooth it out immediately. Carry out the process in the order of first up and then down, and then press it quickly. The heat should be controlled when pressing, so that no water marks appear or the press is loose. After pressing, use a brush dipped in water to clean the dusty areas on the surface. During construction, it is not advisable to remove the entire wall. If there are holes reserved for construction, it is appropriate to remove the entire wall and wait for it to be plastered.
Acceptance of double-sided plastering
1. Before plastering, dust, dirt, oil stains, etc. on the surface of the base layer should be removed and moistened with water.
2. The variety and performance of materials used in decorative plastering projects should meet the design requirements. The cement's setting time and stability retest should be qualified. The mix ratio of mortar should meet the design requirements.
3. Plastering work should be done in layers. When the total thickness of plastering is greater than or equal to 35mm, strengthening measures should be taken. For plastering on the surface where substrates of different materials meet, reinforcement measures should be taken to prevent cracking. When reinforcing mesh is used, the overlap width of the reinforcing mesh and each substrate should not be less than 100mm.
4． The plastering layers must be firmly bonded to each other and between the plastering layer and the substrate, and there should be no delamination, hollowing or cracks in the plastering layer.
5． Use a small hammer to gently tap to check whether there is any hollow sound. If the area of ??hollow but not cracked is no more than 200cm2, it is qualified and all inspections are required. Analysis of plastering acceptance criteria: The surface should be clean, with smooth joining and rubbing, straight line angles, firm bonding, and no delamination, dust explosion, cracks and other defects. Before construction, all the walls and top surfaces must be inspected first. If there are original hollows, they must be eradicated before plastering can be carried out.
Precautions for plastering
1. The yin and yang angles of wall pillars and doorways: There are two types of yin and yang angles: square and straight. During plastering construction, make L50×5 50 cm long angle iron tools to straighten the yin and yang angles, and use a square ruler to control the yin and yang angles; check frequently during construction.
2. Plastering surface layer: When constructing the retaining wall, common problems are: the covering white plaster or plain cement slurry is applied too late, the pressed surface cannot be smoothed, and there are small ridges; during paint construction, you have to use sandpaper to remove the small ridges. Grinding is labor-intensive and time-consuming.
3. The location of the internal and external wall handover window: In some projects, the interior wall is aligned with the frame column edge, and the frame column edge also serves as the window edge. At this time, during construction, you must wait for the exterior wall tiles to be arranged before constructing the interior wall. Avoid constructing the interior wall first and then constructing the exterior wall tiles if the interior and exterior walls are on different sides at the window location.
4． The position of the wall skirting board, the ceiling elevation position, and the flatness: When the plasterer is operating, the scraper rod often cannot be placed at the skirting board position and the ceiling elevation position, causing the flatness of these two positions to be poor. During the construction of the skirting board, it is possible to ensure that the top of the skirting line is straight, but it cannot ensure that the thickness of the top of the skirting line is uniform.