Ash Removal from the Ceiling of Prefabricated Panel Houses

Ash removal from the ceiling of prefabricated panel houses should be judged and carried out in a standardized manner according to specific circumstances. Here are detailed suggestions:

Reasons for Ash Removal

1. Material Quality Issues: The quality of the ceiling white ash (white putty) delivered by developers is usually poor. If putty is applied and paint is brushed directly, the adhesion between the new and old powder layers is insufficient, and problems such as ash generation, blistering, and even peeling are likely to occur in the later stage.
2. Impact of Structural Characteristics: Cracks may exist at the joints of prefabricated panels. Thermal expansion and contraction can cause the ash layer to crack. When materials such as paper-reinforced lime reach their service life, or when the adhesion of ordinary paint decreases after being invaded by moisture, ash shedding may occur.

Criteria for Judging Ash Removal

1. Quality Inspection of Plain Ash: Gently scrape the ceiling with the tip of a scraper. If only a small pit is left and there is no significant shedding, it indicates that the quality of the plain ash is good and can be retained. If the board wall is exposed or pieces fall off with one scrape, it needs to be removed.
2. Inspection of Wall Conditions:
   • If the putty or plaster is applied too thickly and the surface turns white at the corners of the walls or the joints of the top panels, it is recommended to remove it because its adhesion may be poor.
   • Carefully check for ceiling cracks (which are easier to detect after applying glue) and hollowing (judged by knocking and listening for sounds). If such problems exist, removal is necessary.

Key Points of Ash Removal Operations

1. Tool Selection: Using a sharp scraper can improve the removal efficiency.
2. Moistening Treatment: Before removal, spray water to moisten the ceiling appropriately to avoid excessive water spray causing water seepage. You can also use a roller to dip in water and roll it multiple times, or directly flush with water and wait for half an hour before removal.
3. Degree of Removal:
   • For loose areas, scrape to the paper-reinforced lime layer or the concrete layer.
   • For hard areas, only remove the putty layer.
   • For loose areas in the living room, remove the underlying paper-reinforced lime.

Subsequent Treatment and Precautions

1. Cleaning and Repair: After removal, clean up the dust and debris in a timely manner, repair uneven or damaged areas, and polish them. After scraping each ceiling, apply wall consolidator (base film) to seal the dust and enhance the adhesion of the putty.
2. Safety Protection: Wear a dust mask and goggles during operations to avoid inhaling dust or flying debris. Keep the working environment well-ventilated.