This plastering guide will take you through each stage of plastering. The method has been proven during training courses to be the most successful format for complete beginners to achieve a professional finish. This does not mean you will become a plasterer overnight but you should be able to plaster a wall to a professional standard. The first wall you plaster may take all day – but taking the time to ensure your technique is correct will mean your speed rapidly increases.
The best approach is to have a go – this is sometimes the only way some aspects of this guide will make sense (see practice page). If after having a go something does not make sense or you just can’t seem to get the results you want then use the Help Section.
Using this plastering guide
The directions of application in this manual apply to people that are right handed. If you are left handed simply reverse them. (i.e. If right to left is stated then a left handed person will find it easier to reverse this to left to right).
BACKING COAT DETAILS
The backing coat is responsible for flatness.
The purpose of the backing coat is to achieve a totally flat surface – it doesn’t matter how rough it is as long as it is flat. Average thickness is 12mm.
The skim (finish) coat is responsible for smoothness.
A smooth finish is obtained by applying a skim coat of finish plaster. The skim coat is applied to the backing coat at a thickness of 2-3 mm. It is not designed to flatten, but is literally just a smoothing off coat. The Skim Coat is explained in section 2.
All walls need a backing coat except
Plasterboard walls - the plasterboard acts as the backing coat as it is totally flat. If for some reason the plasterboard is not flat then a backing coat of ‘Bonding Coat’ can be applied.
Previously Plastered Surfaces - for example – when the wallpaper has been removed in old houses the wall behind although flat may be in too poor a condition to apply paint. Therefore a skim coat should be sufficient.
Average thickness of a backing coat is 10 to 12 mm thick. If the wall you’re plastering is flat and has no cables that need to be buried you may be able to apply a coat of 10mm or less.
The thickness of backing coat will depend upon the wall you are working on. Sometimes the thickness will be set for you – if you have a door lining in the wall, then the backing coat should finish flush with this lining.
If you have an external corner on your wall then your first job is to fix an angle bead on the corner – this will give you a straight edge to work to whilst also setting the thickness for the whole.
If you have a wall with no external corner plaster this first – angle beads are explained later. Then once you are a bit more familiar with plastering the fixing of angle beads will be a lot easier.
All rights reserved. No part of this online plastering guide may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without the prior permission of the author. Copyright © Paul Harper DIY Plastering 2015
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.