Backing Coat application

Your trowel is only used to apply the thickness of plaster required. A straight edge is taken across the wall to flatten it. Initially when your trowel is loaded with plaster, the leading edge of the trowel will be a long way from the wall. As the amount of plaster on your trowel reduces the leading edge will need to be gradually pushed closer into the wall.


Ruling the plaster flat with a straight edge.

The following technique is explained on an average type of wall. The principle can be applied to any wall no matter what the shape or size – just adapt it as needed.


The straight edge is used to flatten the plaster – by sweeping it across the wall to remove the high areas.


The low areas (those to thin to be marked by the straight edge) can then be filled out with more plaster. The straight edge is then taken across to rule the excess off these areas.


The difficult part is to keep the straight edge flat to the wall and ensure you do not dig in.

To ensure you end up with a totally flat wall, guides for the straight edge are used....

This method ensures that whilst practising you are guaranteed good results. It is important to remember that these guides can be used on any wall whatever the shape or size - just adapt the basic principle to suit the project. Vertical guides on a wall that is longer than your straight edge are not accurate as horizontal flatness over the whole wall is reliant upon the thickness of plaster.



Getting Started · Your first wall may take some time – but get the basics right your speed will rapidly increase. · Take the time to see how the trowel and straight edge can work for you.

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The author cannot accept liability for the use of any of the materials or methods recommended in this manual or for any consequences arising out of their use. The author cannot guarantee the suitability of any recommendations made in this manual and shall not be under any legal liability of any kind in respect of or arising out of the content of this guide.