Advice on lime plastering please

Status
Not open for further replies.
L

lewis26

New Member
Hi
I have been asked to look and price for a job for lime plastering,as havnt done a great deal of this i would appriate some advice please.is there much difference between this and the normal stuff.cheers
 
ok it is normally done in three coats but if you are just patching up you can probably get away with two (three coats scratch,float and set. but for your patching it will be just float and set)

so for the floating coat you want to use your lime mixed with fibres an apply it to a slightly damp background, you should apply this and rule it off like floating with sand and cement, if it is a big surface then you might want to use screeds (use the same mix ratio) leave this a few mill shy of the surface and when you have let it stand for a while key the surface with a devil float this should then be allowed to dry but not fully and shrink (if you are using hydrated lime it will not set but it will go hard when it dries out). then for the finishing coat (setting stuff). the right amount should be mixed at a ratio of 3-1 sharp fine sand - lime then it should be allowed to stand for a while until nearly hard but not dry and then mixed up again (knocked up), it is layed in two coats, this is then rubed up with the float and towelled then brushed. you rub it up 3 times with the use of water, between rubing up you should let the work stand. then for the troweling wich should be troweled 3 ways, first vertically second horizontally third diagonally and if your trowel sticks you can use water, then with a damp brush it is brushed three ways jut like troweling, then it is brushed three ways again with a dry brush

you can use gauged stuff which is lime sand and plaster (gypsum class A) this speeds things up a bit but it is a bit more complicated so seen as how it is only patching up i wont bother going into that.

i hope this helps mate ;)
 
Kirk didnt mention that you leave each coat a minimum of 3 days to carbonate before applying the next coats also you will have to use NHL2 at a mix ratio of 5 sand 2 lime millrig meadow is the best for the backing coats and the top coat should be any of these White Morn Scarr, Hawkstone Gold, Rose Cavern, Middlerigg Ruby, Mosswood Gold, Elm Cragg
 
with lime you have to leave successive coats until they split which can take up to 2 weeks in winter , in hot weather you have to make sure you cure the lime slowly by giving it a mist spray of water every day else it will become drummy or dusty , if using externally you can use a pozzalan which will speed up the carbonation , price wise will vary from 50m2 to 60m2
 
Render Systems said:
Kirk didnt mention that you leave each coat a minimum of 3 days to carbonate before applying the next coats also you will have to use NHL2 at a mix ratio of 5 sand 2 lime millrig meadow is the best for the backing coats and the top coat should be any of these White Morn Scarr, Hawkstone Gold, Rose Cavern, Middlerigg Ruby, Mosswood Gold, Elm Cragg
Click to expand...

i did say not to let it dry but not fully, it my be three days in some cases and not in others and that is why i said when it is nearly dried.


oh by the way, i just love the way alot of people on here never post advice but just take the piss. ;D
 
if your using lime internally white lime is better than nhl, , externally nhl is easier to "look after" until its actually set and is more forgivin of damp conditions,tbh i would use white lime in any situation as imo a more flexible plaster, i can see the benefits of nhl in damp conditions but convenience and cost usually over takes quality and time in most situations
 
fat lime, lime puttty , slaked lime think different areas got different names, but yeah hydrated lime basically.
 
Lime putty is as you say is slaked and normaly 3months old or more the older the better hydrated lime is the white powder you put with sand and cement though i have used it 3and 1 internaly with no probs.
Lucius
 
Status
Not open for further replies.

Share this page

Back
Top