Plastering a Flat Wall


What to aim for…
You should see continuous straight edge marks throughout. Small areas where the straight edge has not touched are hollows - as a general rule if they are smaller than the size of a tennis ball they do not need to be filled as the next stage – ‘Floating’ will cope with them. If you have extensive ridges in your wall, taking the straight edge over the whole area in a sweeping, wave motion will flatten them. Even pressure on the straight edge should be applied at all times. Don’t worry too much though as generally the float will take care of them. Do not worry about getting the straight edge right into the corner – this will prove to be ineffective. It is far better to leave a surplus amount of plaster in the very corner to be sliced off and flattened with the float later.

By splitting the middle area between the guides into sections and ruling off each section before starting another ensures it does not become too dry before you have had a chance to rule it off. This will also have the added benefit of giving you a reference point of the thickness of plaster required for the next section.

The top section

Walls may be very different in height but the technique for plastering the top section is the same.


• Apply the plaster in an upward fashion. Just as before a thin 1st coat to ensure the plaster is stuck properly. The second coat can then be applied to achieve the required thickness.

• Starting with your trowel at the top of the top guide apply the plaster to the top section. When your trowel hits the ceiling flatten it in to the wall (no leading edge - your trowel will be totally flat) and apply extra pressure to the front of your trowel as you ease the back away, whilst moving it from left to right. This ensures lots of pressure can be applied to the small area of the front of the trowel successfully pushing the plaster on, right at the top of the wall.


Extending the flatness

Once the plaster has been applied it can be ruled off flat with the straight edge...

If the straight edge is taken right to the top in one go it is liable to either dig in or come away from the wall......

...therefore the straight edge should be kept firmly on the section of wall that has already been ruled off but should be high enough so that the straight edge starts to scrape off the first 50mm of excess plaster you have applied to the top section. This process of nibbling away at the excess should be repeated until you reach the top of the wall. Always ensure straight edge is kept firmly on the original part of wall.

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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.