The most easily neglected details in the wall pain

  • Detail

The old house has never been inhabited. Some parts of the wall are flat and intact, and a small part of it has been peeled; Now I want to paint the wall again. What should I pay attention to? If only the place is shoveled off and painted on the basis of the original wall surface after leveling, is it OK and how about the quality? Painting the wall is an important process in the process of home decoration, but wall painting is a technical job, and a little carelessness is prone to various problems. For example, it often occurs on the vertical surface of the wall or where the vertical surface meets the horizontal surface (edges and corners), and the paint film at the sagging place is thicker than that on other surfaces. Most of them are caused by excessive dilution of paint and excessive amount of painting at one time

the painting of second-hand houses is different from that of new houses. The re painting of second-hand houses is a renovation process, which is a very huge project. Because the wall base of secondary decoration is very complex, the materials and processes are different, and the wall treatment is also very troublesome, so there are naturally many matters needing attention in the decoration of old houses. During the construction process, there will also be some common problems. For example, inadequate construction preparation, improper surface grinding, excessive painting or too thin paint, too much dipping of the brush each time and other reasons are prone to brush quality problems. Therefore, it is necessary to understand the precautions of wall painting in the decoration of old houses! If you have this need, you might as well come with me to understand it

precautions for wall painting of old house decoration

we formulate different construction schemes according to different building bodies

I. the internal and external walls of new buildings are generally divided into: A. main body cleaning. B. Puttying C. Polish with sandpaper D. Seal Primer on one side. E. Apply on both sides

II. The internal and external walls of old buildings are generally divided into: A. clean the building walls first, and then repair them. B. Finally, paint the primer and finish according to the situation. (the above is only the construction scheme provided by Party B unilaterally. The specific construction scheme shall be carried out according to the actual site conditions and Party A's requirements.)

construction scheme for exterior wall paint painting:

I. substrate requirements:

the most basic requirements for the painted surface of architectural paint &mdash& mdash; Dry, firm and clean

1. drying: maintain the cement wall for at least 1 month (7 weeks in winter), the humidity is less than 6%, and the humidity on the wood surface is less than 10%; The wall surface is free of water seepage, cracks and other structural problems

2. Firm: there is no powdered loose matter, and there is no loose paint on the old wall

3. cleaning: no oil, grease, mold, algae and other adherents

if the substrate does not meet the requirements, it will seriously affect the performance of the paint film. High wall humidity may cause blistering, peeling and peeling of the paint film, as well as alkali seepage on the wall, gloss loss of the paint film and even mildew; Loose substrates with dirt adhesion will affect the adhesion of the paint film, resulting in peeling, peeling and other phenomena. If there is mold breeding, it will also cause mold on the paint film

II. Substrate treatment:

1. New wall surface. After maintenance for more than 1 month, the humidity is less than 6% (can be tested with a hygrometer), and the floating ash stain and alkali exudation are removed

2. Old wall. Wash with high-pressure water or mechanically polish to remove ash and possible bacteria and algae, wash and dry. If necessary, brush with anti mildew solution (10% solution can be prepared with bleaching powder), and then wash with water; The old coating is intact and can be recoated directly after cleaning the surface; The old coating has chalking, blistering, cracking and peeling, so it is necessary to remove the old coating and repaint one coat of primer and two coats of finish paint

3. walls with wallpaper. The wallpaper can be torn off, the glue washed off, and the paint can be applied after proper treatment according to the wall condition after drying

4. Glass fiber surface. The finish paint can be applied directly

5. wood. The worn and rotten parts of the surface shall be removed or replaced, the surface shall be cleaned and repaired, and the joint of doors and windows and walls shall be filled with elastic fillers

6. metal surface. Iron: remove the rust spots on the surface first, and brush the corresponding anti rust primer immediately after cleaning; Non ferrous: remove the oil stain and oxide layer on the surface, and brush the primer with increased adhesion

III. wall treatment:

1. If the wall is flat, it is recommended not to use putty

2. if putty is used, it is easy to apply it thinly rather than apply it thickly

3. In addition to being easy to approve and polish, putty should also have good strength and durability. For exterior walls, kitchens and toilets, the requirements for putty should have better adhesion, adhesion durability and water resistance

4. Treatment methods for possible problems on the wall: dust, powder &mdash& mdash; High pressure water can be used to wash outdoors and wet cloth can be used to wipe indoors; Grease &mdash& mdash; Clean with neutral detergent; Mortar &mdash& mdash; Remove with shovel, scraper, etc; Mold &mdash& mdash; Wash with high-pressure water outdoors, scrub with bleach indoors for a few minutes, rinse with clean water and dry

IV. construction conditions:

latex paint has high requirements for construction and maintenance conditions because it is a water-based paint. The construction and maintenance temperature is higher than 5 ℃, and the environmental humidity is lower than 85% to ensure good film formation. Low temperature will cause problems such as pulverization and cracking of latex paint film, and environmental humidity will prevent the paint film from drying for a long time, which will eventually lead to poor film formation. Weather factors must be taken into account in the construction of exterior walls. It is not allowed to rain for 12 hours before painting emulsion paint to ensure that the substrate is dry; After painting, it shall not rain for 24 hours to prevent the paint film from being washed away by rain

v. coating system:

the general coating system for exterior wall construction is divided into three layers: primer, intermediate paint and finish paint

1. primer. The primer closes the wall alkaline, improves the adhesion of the finish, and has a great impact on the surface coating performance and surface effect. If the primer is not used, the adhesion of the paint film will be weakened, and the alkaline wall surface will have a greater impact on the performance of the paint, especially the bottom surface of white cement putty, which may cause the problems of paint film chalking, yellowing, alkali seepage, etc., damage the performance of the finish paint, and affect the service life of the paint film

2. intermediate painting. The main function of intermediate paint is to improve adhesion and hiding power, provide three-dimensional patterns, increase fullness, and correspondingly reduce the amount of finish paint

3. finish paint. Topcoat is the last coating in the system, which has decorative function and resists environmental infringement

VI. coating skills:

to achieve good coating effect, skilled operation level is required, but the construction of emulsion paint is not very difficult. First of all, the substrate should be clean, dry and firm. Operate according to the instructions. The coating conditions are suitable, and the dilution ratio is accurate. Excessive dilution will make the coating not cover the bottom and powdered, and the glossy coating will lose light and have different colors. Secondly, good construction tools are also necessary

the painting sequence of exterior wall painting should be from top to bottom, from roof, gutter, column top, beam and rafter to wall, door, window and base plate. Each part shall also be painted from top to bottom. When painting each part, you can't stop halfway. If you have to stop, you should also choose the original connection parts of the house structure, such as the connection between the wall and the window frame

this will avoid ugly seams. When painting the cornice board, it should be divided into the following two steps: brush the bottom of the cornice board first, and then the sunny part. When painting several eaves boards at the same time, move the ladder and follow the wall in turn. Move quickly in the painting process. Brush back and forth at the dry and wet joints from time to time to avoid leaving laminations or joints

in general, the painting of the wall basically follows several conventional steps, but occasionally there are differences, such as the painting of new houses and second-hand houses. There are still some differences in the early wall treatment. Therefore, when decorating, if there is a renovation of second-hand houses, the owner should pay special attention

new houses: many new houses are clean houses, that is, only the interior walls are plastered with cement mortar, that is, houses without any interior decoration, or houses that have only been puttying If only cement mortar is used for troweling and painting, the following steps can be carried out in sequence after leveling and then puttying Compared with the old house, the preliminary treatment of the new house is simpler

second hand houses: repainting second-hand houses is a renovation process, which is a very huge project. Because the wall base of secondary decoration is very complex, the materials and processes are different, and the wall treatment is also very troublesome, so naturally there are many matters to pay attention to

painting 1

first, whether the wall paint should be eradicated

1. In the short term: for the wall of the purchased second-hand house, if it is not decorated for a long time, the original water-resistant putty can be retained during the wall treatment, and it does not need to be completely removed; Polish the wall with steel brush and sandpaper, and then re paint the emulsion paint

2, the time interval is too long: if it is a water-resistant putty with more than five years, due to the aging of the material, it must be completely removed to the bottom of the wall when painting twice, otherwise it will affect the construction quality of the wall emulsion paint in the future and the long-term use effect after decoration

3, how to clean the wall:

1 water on the wall: wet the original wall and save effort when shoveling

2 shovel the wall: remove the part of the original wall that has been soaked in water until the cement mortar wall or putty layer is exposed

second, the wall should be fully repaired

generally speaking, it is difficult to achieve the desired effect for the repair of painted walls Therefore, when renovating the wall of the second-hand house, the owner must repair it comprehensively. For the repair of the damaged wall, it is best to repair the whole wall or choose a larger area as much as possible. In this way, the color difference can be avoided as much as possible, and the quality after repair is also better


1, repair the wall: if the cement wall has cracked or is not strong, you can shovel it off and re trowel it with cement mortar. If it can still be used, you can omit this step

2, interfacial agent: the wall surface shall be painted with interfacial agent, which must be brushed evenly

3, cracks: generally, stick the cracks with kraft paper tape and white latex (but it can't be guaranteed that 100% will not crack again)

4, leveling: uneven walls need to be leveled. Generally, gypsum is commonly used, and the concave convex difference is not more than 0.5 cm

5, pasting: generally, non load-bearing walls such as light body walls and thermal insulation walls need to be pasted. Try to choose wall cloths and white latex with better texture. If conditions permit, you can use mesh cloth, which will have a better crack prevention effect

painting 2

third, pay attention to ventilation after painting

in addition, pay attention to ventilation of second-hand houses after painting, especially for second-hand old houses, the ventilation conditions are poor, and the xylene component in the diluent will react with the component in the emulsion paint, resulting in yellowing of the wall Therefore, to strengthen ventilation, it is really not feasible. We have to place several electric fans to enhance the ventilation effect

how much is it to paint a square meter?

first, the uncertainty of paint selection, we all know that different wall paint prices are very different. Therefore, there is a big gap in the cost, so the cost of painting walls per square meter is naturally different

second, the difficulty of the wall surface. If it is a very worn wall surface, or some walls are shaped, it will bring considerable difficulty to the construction. Therefore, it is common sense that the price is slightly higher than usual at this time

III. The effect requirements of wall painting are different. Some friends have particularly high requirements for the effect of wall painting, especially in some high-end hotels, which need colored paint





Copyright © 2011 JIN SHI