[construction] construction technology of external wall elastic coating

1. base treatment

1. The cement on the new wall should be cured for at least one month, so that the alkalinity of the wall surface should be properly reduced and the wall surface should be dried thoroughly. The moisture content of the wall surface should be lower than 10%; If the ambient temperature is low, the waiting time of the wall surface will be extended accordingly.
2. Remove dust and other adhesion on the surface of the base layer. When the wall is flushed with zinc sulfate solution or dilute hydrochloric acid solution, the oil is cleaned with detergent, and finally washed with water.
3. Check the substrate for signs of hollowing
If the hollowing is not handled, the coating film will eventually fall off with the hollowing part of the substrate. Therefore, hollowing should be immediately removed and repaired. After the hollowing part is repaired, it shall be maintained according to the regulations, and the construction can only be carried out after meeting the requirements, so as not to cause defects in the coating film. It is forbidden to repair on the same day and paint on the next day.
4. Check the substrate for cracks
Regarding the treatment method of cracks, putty is generally used to fill after cleaning; elastic putty should be used for batch embedded cracks to ensure that when the external force makes the cracks further expand, the putty prevents the emergence of cracks to a certain extent.
2. putty batch scraping
If the wall is flat and can meet the construction requirements, it is not necessary to batch putty. If it is necessary to level with putty, when scraping putty in batches, try to scrape as little and as thin as possible. The interval between two putty in batches should not be too short. A surface layer of putty should be scraped after the former bottom layer of putty film is completely dried and trimmed. Finally, polish and smooth.
3. brush primer
Apply the special alkali-resistant sealing primer evenly on the cleaned base with a roller. Do not miss the coating, and do not apply too much to cause flowing or accumulation.
Before primer application, please confirm whether the substrate meets the coating requirements according to the following requirements:
1, flatness: side to strong light inspection, should be no obvious bump visible.
2. Dense and not loose: Digging the wall surface with fingers should be hard and without looseness. If the substrate is too loose, it will cause defects such as foaming and falling off of the coating film during airless spraying construction.
3. Water resistance: wipe the wall with your fingers dipped in water, and the putty should have no swelling phenomenon.
4, check the substrate without hollowing, cracks, sand holes, particles and other ills
5. Clean the surface clean without dirt.
4. finish construction
Check whether the model and specification of the topcoat are consistent with the requirements, and whether the quantity is consistent with the area to be painted, as much as possible. Before construction, the coating shall be fully stirred and diluted according to the construction instructions for standby.
1. After the putty is completely dry, (more than 24 hours/25 ℃), apply the first topcoat. Flow drops are not allowed.
2. After the first topcoat is dried (more than 2 hours/25 ℃), apply the second topcoat. Penetrating the bottom and falling are not allowed.
5. brushed varnish
After the finish paint is accepted, the finish paint shall be painted as a whole, and the paint shall be kept consistent without missing or hanging.
6. coating quality inspection and finishing work
After the painting is finished, all the equipment used for masking shall be removed in time, and the dry coating film shall not be damaged. Check that the coating film has no defects such as sagging, shrinkage cavity and over-spraying. The coating film should be smooth and uniform in color.
Note:
1. Primer and topcoat generally do not need to be diluted. Excessive dilution will lead to the appearance of the wall powder phenomenon. The paint needs to be thoroughly mixed before use.
2, external wall construction, the ambient temperature should not be lower than 5 degrees Celsius; the same ambient temperature should not be too high. If the construction is in the summer high temperature season, the wall is under direct sun exposure, please wet with clear water or add 10% clear water in the paint, so that the paint will not dry too fast to form a perfect paint film.
3. The PH value of the construction wall surface should be lower than 10, and the moisture content should be lower than 10%.
4, before and after construction should pay attention to the weather conditions, avoid rain and snow weather. The paint must be protected from rain and dust during application and before drying.
5. After the construction is completed, there should be at least 1 week of maintenance period. During this period, attention should be paid to the protection of the wall, and touch, cleaning, and collision should be avoided as much as possible.
6, avoid contamination of the skin, such as contaminated skin should be washed with soap and water; such as stained eyes, should be immediately washed with water or diluted boric acid for at least 10 minutes, and to the hospital for treatment.
7, placed in a place where children can not take.