Plastering Technique

The correct plastering technique is essential - with only the trowel being used to apply and finish the skim coat.

Achieving a good finish

Is the combination of firm pressure combined with the correct angle of your trowel (how far the leading edge is from the wall)

trowel techniqueAs the trowel moves up the wall - and when firm even pressure is applied to the trowel it will gradually fold into the wall as the amount of plaster reduces

Plastering Technique for applying plaster

click here for plastering technique to 'trowel' plaster and smooth out

Initially when your trowel is loaded with plaster, the leading edge of the trowel will be a long way from the wall. As this amount plaster reduces the leading edge will need to gradually be flattened into the wall.

Plastering Technique for applying plaster

With the next stroke the trowel will be used for flattening out what you have just applied. There will be no plaster on your trowel and it will be fairly flat - the leading edge will be approximately 10 – 15 mm away from the wall.

This combined with firm pressure will push the plaster flat and even.

You cannot push too hard - providing you have the correct angle of your trowel. If the leading edges is more than 15 mm away from the wall then the trowel will start to scrape plaster off the wall. Close this angle down so that it is 10 - 15 mm away and you can push as hard as you like and it will give you a nice clean even, hollow free application. This plastering technique is crucial to learn so go as slowly as you need to so as to maintain good technique at all times. With the correct technique your speed will then increase very quickly.

plastering technique

Plaster has its own timetable!

Many beginners try and do too much too soon and are often surprised at just how much can be achieved when the plaster is quite firm.

The six stages of skimming...

...Skimming is definitely not a case of applying the plaster and smoothing out immediately – there are many situations that can only be resolved in the later stages. It is also not a case of just moving from one stage to the next. Progression through the stages is determined by how quickly the plaster starts to firm up. You move from one stage to the next once the plaster has firmed up and gone tacky.

If at any stage you do not see any improvement then this does not necessarily mean there is anything wrong with your plastering technique but probably that the plaster is too wet. In the early stages the objective is flatness not smoothness. The smoothness will come later – but only if you have achieved flatness so do do always remind yourself of the objective of each stage.

Plastering technique - the 6 stages of skimming

The setting process

The plaster can firm up for two different reasons either:

• due to the natural setting process

• or due the moisture being sucked out of the plaster by the backing coat.

The single most important aspect to be aware of is suction.

If you don't have it under control then no matter how good your plastering technique is you will never be able to achieve a good finish.

The suction test should always be carried out.

If you are applying the skim coat on plasterboard then you need not worry as the suction is controlled for you with the paper. In some instances if the backing coat is very porous the moisture can be sucked out almost instantly. This is definitely not good as by the time you have finished applying plaster to the whole wall, the first application will be totally dry and therefore firm which will make it very difficult if not impossible to carry out the next stages.

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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.