YOU WILL NEED:
- Plastering Trowell
- Large Mixing Bucket
- Paddle Accessory & Power Driver
- Multi-Finish Plaster
- Angle Beading For External Corners
- Scrim Tape Any Board Joints
Plastering needs practice & a good technique for perfect results but it’s possible to tackle smaller areas with good results. Ceilings to the professionals. Here’s how to add plaster skim coat to a new plasterboard wall:
Step 1: Prepare The Room
Clear the area of furniture & spread plenty of plastic sheeting over the floor. If you are plastering over new plasterboard, press scrim tape over all the board joints & screw metal reinforcing angle bead to all external corners.
Step2: Mix The Plaster
Mix your plaster according to the instructions on the bag. Always add plaster to the water & use a clean mixing bucket. It’s essential to mix the powder & water thoroughly so that you have a thickish, creamy consistency with no lumps. A paddle accessory fitted to a corded electric drill is the best method of mixing. Plaster can set in minutes, especially in the summer, so only mix an amount you can use immediately. Don’t add new plaster to an old mix & don’t add water to the plaster to try & make it more workable.
Step3: The Base Coat
Scrape a trowell full of plaster off the mixing board & onto your hawk. Next, transfer half the plaster to your trowel. Keep your trowel wrist straight & use flicking action with your “hawk hand” to move the plaster from hawk to trowel. Working from the bottom of the wall, use smooth strokes to press the plaster onto the wall. Gradually narrow the gap between the trowel’s top edge & the wall as you move the tool upwards. Always keep the trowel at a slight angle to the wall at the end of the stroke. If trowel is flattened against the sirface it may pull the new plaster away from the wall. Work over the whole area to apply a base coat – dont worry about an uneven area or hole at this stage. This coat should be around 2mm thick. Use the angle beading as a guide when plastering up to external corners.
Step4: Smooth The Surface
Clean around the edges of the waal with a wet paintbrush to remove lumps and lines of plaster that are on the ceiling or adjacent walls. The next stage is to level and smooth the surface but this can only be done when the plaster has hardened slightly but is still pliable. This working time will vary from a few minutes in summer to 20 minutesor more in very cold environments. Use your trowel at a very shallow angle to the wall & work over the surface smoothing the surface. You can add a thinner skim of more plaster to fill holes and even out depressions.
Step5: Drying & Polishing
Leave the plaster to dry once more – for around 30-40 minutes. The plaster can be polished. Wet the surface of your trowel & flick the water on the wall with a large paintbrush. The idea is to provide just enough lubrication for your trowel to float over the surface & fill tiny holes and imperfections. Work in regular sweeping strokes & finish with long continious stroke across the wall. Wash your mixing board & tools as soon as you’ve finish work. Dont keep opened plaster bags for more than a couple of weeks.