Filling and sanding walls smooths imperfections like holes and cracks before painting or decorating. The process involves applying filler and then sanding it flat once dry.
To fill and sand walls effectively, you typically follow these steps:
Preparing the Wall
Before applying any filler, make sure the wall surface is clean and free from loose debris.
- Clean the area: Brush away dust and loose plaster around the hole or crack.
- Remove loose material: Gently widen any cracks slightly using a scraper to ensure no loose material remains.
Applying the Filler
Choose a suitable wall filler based on the size and type of damage.
- Use a scraper to apply the filler firmly into the hole or crack.
- Ensure the filler is pressed in well to completely fill the void.
- For any holes that are more than 10mm-deep, build up the filler in layers. Allow each layer to dry sufficiently before applying the next to prevent shrinking and cracking.
Drying Time
Allow the filler ample time to dry. The drying time can vary depending on the filler type, layer thickness, and humidity.
- Allow to dry for one to two hours for thinner applications or layers. Deep fills will require longer. Check the product instructions for specific drying times.
Sanding the Filled Area
Once the filler is completely dry and hard, it's time to sand.
- Use fine-grit sandpaper (e.g., 120-grit) wrapped around a sanding block or on an orbital sander.
- Sand until smooth, working in circular motions or long strokes across the filled area. The goal is to make the filled patch flush with the surrounding wall surface.
- Be careful not to over-sand, which can create a dip.
Final Clean-up
After sanding, there will be dust.
- Give the wall a final once-over with a duster or a damp cloth to remove all sanding dust. This ensures the surface is clean and ready for priming or painting.
Summary of Key Steps
Here’s a quick overview of the core process:
| Step | Action | Reference Detail Incorporated |
|---|---|---|
| Apply | Fill the hole/crack with filler | Use a scraper; Build up layers for >10mm deep holes |
| Dry | Allow filler to harden | Allow 1-2 hours (per layer/final) |
| Sand | Smooth the dried filler flush with the wall | Sand until smooth |
| Clean Up | Remove dust | Give the wall a final once-over with a duster |
By following these steps, you can effectively repair imperfections, leaving your walls smooth and ready for their next finish.
