Lime Plaster - Revision history

Robinsonj: additional guides

2019-11-05T01:07:03Z

additional guides

Robinsonj: /* Tools required */

2019-11-04T23:53:36Z

‎Tools required

Robinsonj: /* Internal Lime Plaster */

2019-11-04T23:13:08Z

‎Internal Lime Plaster

Robinsonj: John Edwards video

2015-12-30T02:53:53Z

John Edwards video

Robinsonj: Ty Mawr video

2015-12-30T01:56:31Z

Ty Mawr video

Robinsonj: Tools

2015-12-30T01:45:09Z

Tools

Robinsonj: First content

2015-12-30T01:17:04Z

First content

New page

==Internal Lime Plaster==

Typically three coats of varying consistencies of lime mortar and plaster but can be four if a harling coat is also used and even five if the wall is uneven enough to require dubbing out.

A thin 'harling' (or thrown) coat to provide a key and control suction (particularly on cob or brick) - optional (3:1 made sloppy with extra water)
A dubbing out coat to fill any deep depressions where a flat final finish is required - optional (3:1 haired)
A scratch coat, the body of the plaster, about 10-15 mm thick to roughly flatten the surface, keyed by scratching with a comb to provide a grip for the float coat. (3:1 haired)
A float coat to form a flat base, lightly scratched, for the final finish or top coat (3:1 unhaired).
The top coat or finishing skim, much finer mix applied in two layers (2:1, 3:2 or 1:1 depending how fine finish is required using finer sand)

YouTube Videos

'''[https://www.youtube.com/watch?v=l5Sb6hwaXb0 How to lime plaster an internal solid wall]''' by [http://www.artisanplastercraft.com/ Artisan Fine Architectural Plasterwork]

==External Lime Plaster or Render==

Similar to above, tends to be less fine finish and depending on weather resistance/water control may include a pozzolan in the scratch coat to give an earlier (chemical) set and also reduce water absorbtion/transmission.

[[Category:Lime]][[Category:Plaster]]

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 * '''Water Sprayer''' - to damp the surface to control suction and to keep mortar damp during ealy parts of cure (a couple of days at least). Various sizes depending on areas to be covered, portability and access. Might need a hose if a lot of water is required (e.g. dry brick walls).
 * '''Hawk''' - wood or plastic to carry plaster to the wall and to knock it up to keep it 'fat'.
-* '''Plasterers Trowel''' - 9"x3" upwards, start smaller when you are learning. Used to push plaster (firmly) on to the wall and to finish the skim coat if a very smooth finish is required. Stainless flexible blades are easier to use and longer lasting than stiff carbon steel although much more expensive. A 'Venetian' trowel is easier to use on uneven surfaces as it has a thin blade and the corners are rounded and edges beveled so do not catch as much as a standard trowel.
+* '''Plasterers Trowel''' - 9"x3" upwards, start smaller when you are learning. Used to push plaster (firmly) on to the wall and to finish the skim coat if a very smooth finish is required. Stainless flexible blades are easier to use and longer lasting than stiff carbon steel although much more expensive. A 'Venetian' trowel is easier to use on uneven surfaces as it has a thin blade and the corners are rounded and edges beveled so do not catch as much as a standard trowel. You can also use a '''Pool Trowel''' at the final smoothing stage. They have rounded ends and are far more flexible than square-ended trowels. The combination of the trowels’ round ends and flexibility keeps them from gouging the surface, leaving a smoother finish achieved more easily than with a rectangular trowel. Like finishing trowels, these also come in various sizes.
 * '''Scratcher''' - 6-8 pins in a handle (like a coarse comb) to gently score the surface to provide a key in the scratch coat for the levelling coat.
 * '''Small Trowel''' - approx 8" or could be a bit smaller for detailed work/smaller areas/restricted spaces.
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 '''[https://www.youtube.com/watch?v=4OgjftJ3kU8 Lime Rendering and Lime Plastering Step By Step]''' by [https://www.youtube.com/channel/UCcVt9mmimG4opj3AR6KEMLg Sed Edwards] with [http://johnedwardslime.co.uk/ John Edwards Lime]
 [[Category:Lime]][[Category:Plaster]]

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 ==Tools required==
-* '''Bucket''' - if required to carry harling coat slurry
+* '''PPE''' - Eye protection and gloves as a minimum. Lime in the eyes is very dangersous and happens easily when handling plaster at any stage of the process. Gloves will protect our hand from the caustic drying effect of the lime. Overalls will obviously protect the rest of you and your clothes. A hard hat would be a good idea and essential on most building sites inside and out.
-* '''Hawk''' - wood or plastic to carry plaster to the wall and keep it 'fat'
+* '''Buckets/Trugs''' - if required for water and to mix/carry mortar, harling coat slurry or finish coat.
-* '''Plasterers Trowel''' - venetian trowels are easier to use on uneven surfaces as it has a thin blade and the corners are rounded and edges beveled so it does not catch as much as a standard trowel
+* '''Harling Trowel''' - if required for a base splatter coat.
-* '''Wood Float''' - to smooth the surface and remove any tooling mark, also raised the texture slightly
+* '''Bucket Trowel''' - to put plaster on the hawk.
-* '''Devil Float''' - a float with a couple of lath nails driven through so they just protrude to provide a fine key
+* '''Water Sprayer''' - to damp the surface to control suction and to keep mortar damp during ealy parts of cure (a couple of days at least). Various sizes depending on areas to be covered, portability and access. Might need a hose if a lot of water is required (e.g. dry brick walls).
-* '''Firm Sponge''' - used on the skim to finish the surface
+* '''Hawk''' - wood or plastic to carry plaster to the wall and to knock it up to keep it 'fat'.
 ==YouTube Videos==

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 ==Internal Lime Plaster==
-Typically three coats of varying consistencies of lime mortar and plaster but can be four if a harling coat is also used and even five if the wall is uneven enough to require dubbing out. All coats are a mix of sharp sand and lime putty (i.e. 3:1 is three parts sharp sand and one part mature lime putty)
+Typically three coats of varying consistencies of lime mortar and plaster but can be four if a harling coat is also used (where suction is very poor)and even five if the wall is uneven enough to require much dubbing out. All coats are a mix of sharp sand and quicklime mixed hot with the exception of the finishing coats which can use fine sand and lime putty for a finer finish (i.e. 3:1 is three parts sharp sand and one part quick lime or for a finish coat 1 part fine sand to 1 part mature lime putty)
-* A thin ''''harling' (or thrown) coat''' to provide a key and control suction (particularly on cob or brick) - ''optional'' (3:1 made sloppy with extra water)
+* A thin ''''harling' (or thrown) coat''' to provide a key and control suction (particularly on cob or brick) or to provide a key on impervious surfaces with poor suction - ''optional'' (3:1 made sloppy with extra water)
-* A '''dubbing out coat''' to fill any deep depressions where a flat final finish is required - ''optional'' (3:1 haired)
+* A '''dubbing out coat''' to fill any deep depressions where a flat final finish is required - ''optional'' (3:1 hair/fibre optional)
 * A '''scratch coat''', the body of the plaster, about 10-15 mm thick to roughly flatten the surface, keyed by scratching with a comb to provide a grip for the float coat. (3:1 haired)
 * A '''float coat''' to form a flat base, lightly scratched, for the final finish or top coat (3:1 unhaired).
-* The '''top coat or finishing skim''', much finer mix applied in two layers (2:1, 3:2 or 1:1 depending how fine finish is required using finer sand)
+* The '''top coat or finishing skim''', much finer mix applied in two layers (2:1, 3:2 or 1:1 depending how fine a finish is required using finer silica sand, lime sand or even chalk dust)
 ==External Lime Plaster or Render==

← Older revision		Revision as of 02:53, 30 December 2015
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	'''[https://www.youtube.com/watch?v=DmWQ1X1jYOk&list=PLFSqOXpgBEL7HsP_j3HQv1YQzwrbhJDLi Lime Plaster Application Guide]''' by [https://www.lime.org.uk/ Ty Mawr]		'''[https://www.youtube.com/watch?v=DmWQ1X1jYOk&list=PLFSqOXpgBEL7HsP_j3HQv1YQzwrbhJDLi Lime Plaster Application Guide]''' by [https://www.lime.org.uk/ Ty Mawr]
		+
		+	'''[https://www.youtube.com/watch?v=4OgjftJ3kU8 Lime Rendering and Lime Plastering Step By Step]''' by [https://www.youtube.com/channel/UCcVt9mmimG4opj3AR6KEMLg Sed Edwards] with [http://johnedwardslime.co.uk/ John Edwards Lime]

	[[Category:Lime]][[Category:Plaster]]		[[Category:Lime]][[Category:Plaster]]

@@ Line 8: / Line 8: @@
 * A '''float coat''' to form a flat base, lightly scratched, for the final finish or top coat (3:1 unhaired).
 * The '''top coat or finishing skim''', much finer mix applied in two layers (2:1, 3:2 or 1:1 depending how fine finish is required using finer sand)
 ==External Lime Plaster or Render==
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 * '''Firm Sponge''' - used on the skim to finish the surface
 [[Category:Lime]][[Category:Plaster]]