Application: Plumb and Dot Method of Floating Coat

1. Level 1 Diploma in Plastering
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presentationApplication: plumb and dot method of floating coat
Unit 124: Applying floating coats to wall

2. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Assessment criteria
1.4 describe the importance of correct technique and
procedure when using tools
1.5 describe different types of floating coats
2.4 use methods to apply floating coats
2.5 use correct techniques when applying floating coats

3. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Plumb and dot method
• The plumb and dot method is one of the most
traditional methods of applying floating coats, but
it is still used in high class work and on
long/high walls.
• This can be a very slow and time-consuming
method but it does ensure trueness.
• This method involves forming dots and using a
spirit level to plumb them in. Screeds are formed
from the dots.
• Not to be confused with the term ‘dot and dab’.

4. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Wooden laths are first
cut to 75mm in length
and then soaked
Application

5. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Application
• Apply a small amount of material in
the top right-hand corner,
approximately 150mm from the
ceiling and wall angle.
• Press lath into the material to a
thickness of around 12mm.

6. Level 1 Diploma in Plastering
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Application
• Repeat this process to the top left corner.
• Place laths directly underneath approximately
150mm from the floor.

7. Level 1 Diploma in Plastering
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Application
Once all laths have been pressed
into place, a spirit level and straight
edge are used to plumb them.
This is when the correct thickness
is also set.

8. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Plumb and dot method
Dots should be
cleaned off and
allowed to stiffen
up.
Ruling off the laths,
screeds can be
formed.

9. Level 1 Diploma in Plastering
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Application
Laths can be removed and screeds
rubbed up.
Allow screeds to stiffen up.

10. Level 1 Diploma in Plastering
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Application
Starting in the top
corner, fill in between
the screeds, using the
screeds as a guide to
rule off any excess
material

11. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Application
Once the whole wall
has been ruled in and
is sufficiently stiff, it can
be rubbed up before a
suitable key is applied

12. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Application
On high walls in may not be possible to use a spirit
level and straight edge
In order to set the dots, a plumb bob and gauge laths
would be used
A gauge lath is a piece of timber cut to measure the
protrusion of the dot
Using an identical lath on the lower dot, the plumb bob
should touch in the same point

13. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Upper gauge in position
Gauge
Plumb line
Plaster dot
Lath

14. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Lower gauge in position

15. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Dots being lined in using a plumb line

16. Level 1 Diploma in Plastering
© 2013 City and Guilds of London Institute. All rights reserved.
Any questions?