Lime or sand cement

carys

Well-Known Member
Went to see a job today old stone house in middle of nowhere. He was keen on lime mortar on the outside so I told him that a waste of time becouse inside sand cement and it going to cost more in labour . I told him the other option sand cement waterproofer and it going to work out cheaper.what is your opinion on lime render. Should he spend that extra money to do it rhight. Or go down the the sand cement way and in my opinion is fine.
 

martinemj

Well-Known Member
Sand cement itself is too hard for stone so I would go with a breathable render preferably lime based ...
....once the outside is done any plaster work done inside can then also be breathable be that now or in future
 

carys

Well-Known Member
Sand cement itself is too hard for stone so I would go with a breathable render preferably lime based ...
....once the outside is done any plaster work done inside can then also be breathable be that now or in future
Do you think it be OK whith sand cement inside for now.?
 

martinemj

Well-Known Member
Agree ,Yes ideally ....


The outside wall is always the one to do first
It won't Tick all boxes but will help wall dry from that side which is the weather side
 

carys

Well-Known Member
Agree ,Yes ideally ....


The outside wall is always the one to do first
It won't Tick all boxes but will help wall dry from that side which is the weather side
It seems to me your a expert whith lime. I've a done a bit on off over the years. Do you harle walls first for key.?
 

carys

Well-Known Member
It seems to me your a expert whith lime. I've a done a bit on off over the years. Do you harle walls first for key.?
I did one job harled the place for key just wondering if ther something new on the market make life easier.?? Il phone ty Mawr
 

carys

Well-Known Member
No we are usually asked for a smooth finish
No m8 it makes me think your not a lime expert. I'm not but I'm a plastrer that can pick up things quickly. Harling is a key for lime like Eglinton stiple coat or sbr in sand cement
 

martinemj

Well-Known Member
what's with the above comments you asked for some help
As far as I know Harling is a finish not a preparation so maybe your not so smart

I dont claim to be an expert .....
but have learnt from experience of last 20 years with lime
And like I said externally I have no interest in mono or roughcast finishes purely because I don't like them so i offer a smooth render or a bagged finish ...

When you say about scudding outside that would only be necessary on a poor background
most of our work is onto limestone which is fairly hard and lime sticks to it fine..


I'm done
 
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carys

Well-Known Member
what's with the above comments you asked for some help
As far as I know Harling is a finish not a preparation so maybe your not so smart

I dont claim to be an expert .....
but have learnt from experience of last 20 years with lime
And like I said externally I have no interest in mono or roughcast finishes purely because I don't like them so i offer a smooth render or a bagged finish ...

When you say about scudding outside that would only be necessary on a poor background
most of our work is onto limestone which is fairly hard and lime sticks to it fine..


I'm done
Sorry being out last night I talk s**t when I've had a drink. The bloke I did the lime course always said he was going to harle the walls for key.
 

carys

Well-Known Member
Harling is a term used for finishing coat like rough casting but with lime
First coat is called harling for key in lime work. And term harling is finished product to
 

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FreeD

Private Member
Went to see a job today old stone house in middle of nowhere. He was keen on lime mortar on the outside so I told him that a waste of time becouse inside sand cement and it going to cost more in labour . I told him the other option sand cement waterproofer and it going to work out cheaper.what is your opinion on lime render. Should he spend that extra money to do it rhight. Or go down the the sand cement way and in my opinion is fine.

Think you re unlikely to get the job mate...sand cement internally/externally will destroy the property...at least lime externally it can breath out. If a plasterer even mentioned the word cement to me while quoting work on a stone property would be crossed off the list :LOL:
 
D

Deleted member 32554

Guest
Think you re unlikely to get the job mate...sand cement internally/externally will destroy the property...at least lime externally it can breath out. If a plasterer even mentioned the word cement to me while quoting work on a stone property would be crossed off the list :LOL:
Any problems with foam dabbing thermal boards internally ?
 

carys

Well-Known Member
Think you re unlikely to get the job mate...sand cement internally/externally will destroy the property...at least lime externally it can breath out. If a plasterer even mentioned the word cement to me while quoting work on a stone property would be crossed off the list :LOL:
I've got the job m8. So y did you think I didn't. The first thing I suggested was lime and I told him it more time consuming than modern way but better in the long run Nother options I told him sand cement. So your saying sand cement will destroy the property agree to some point so y are most of stone buildings dashed or whatever in sand cement and they seem OK 20 30 years down the line. I've seen buildings whith lime render ther full of damp becouse they can't cope whith the extreme rain that we get.????
 

FreeD

Private Member
I've got the job m8. So y did you think I didn't. The first thing I suggested was lime and I told him it more time consuming than modern way but better in the long run Nother options I told him sand cement. So your saying sand cement will destroy the property agree to some point so y are most of stone buildings dashed or whatever in sand cement and they seem OK 20 30 years down the line. I've seen buildings whith lime render ther full of damp becouse they can't cope whith the extreme rain that we get.????

Carys there are too many variables...every project is different, but in general cement should never be used on a stone built/lime mortar property.

As you know there are different types of lime render some which are better at resisting the weather and there are paints e.g mineral paints for additional protection...

As you know there can also be issues with ventilation/condensation
 

carys

Well-Known Member
Carys there are too many variables...every project is different, but in general cement should never be used on a stone built/lime mortar property.

As you know there are different types of lime render some which are better at resisting the weather and there are paints e.g mineral paints for additional protection...

As you know there can also be issues with ventilation/condensation
Yes true. But y did lime render go out of it and sand cement being used nearly everywhere. Most stone houses I see are pointed whith sand cement even the Chapel churches are pointed whith sand cement wher I am it might be the reason ther having trouble now days
 

theclemo

Private Member
Yes true. But y did lime render go out of it and sand cement being used nearly everywhere. Most stone houses I see are pointed whith sand cement even the Chapel churches are pointed whith sand cement wher I am it might be the reason ther having trouble now days

Sand and cement come in because its faster and cheaper. Just like boarding come in instead of floating but not as good
 

malc

TPF Special Forces
Yes true. But y did lime render go out of it and sand cement being used nearly everywhere. Most stone houses I see are pointed whith sand cement even the Chapel churches are pointed whith sand cement wher I am it might be the reason ther having trouble now days

by using sand and cement the building trade could work all the year round.
in the days of lime mortar work would stop around Christmas through to Easter. building work was classed as causal labour and not a full time job.
 

worthwords

Active Member
Yes true. But y did lime render go out of it and sand cement being used nearly everywhere. Most stone houses I see are pointed whith sand cement even the Chapel churches are pointed whith sand cement wher I am it might be the reason ther having trouble now days

I'm using lime putty plaster for some parts of my internal DIY work. It is great to work with but takes weeks to finish a wall properly this time of year. In fact you don't want it to dry too quickly as it can become feeble and powdery.

Cement traps moisture within a solid wall structure and re-pointing old buildings with portland will lead to excess moisture in the masonry which will be subjected to freeze thaw cycles and thus spalling - the pointing itself will look ok as the building deteriorates.
Unfortunately 'Lime' is not one thing and it appears that NHL and various things called 'lime' are almost as bad as cement.

This video is quite long but gives an overview of the functional qualities of a porous lime.
 

worthwords

Active Member
Yes true. But y did lime render go out of it and sand cement being used nearly everywhere. Most stone houses I see are pointed whith sand cement even the Chapel churches are pointed whith sand cement wher I am it might be the reason ther having trouble now days
Lots of new , fast, waterpoof materials turn out to be very damaging. Waterproof paints on wood have destroyed many a window frame.
First coat is called harling for key in lime work. And term harling is finished product to
Yeah, i know a harl coat as just a thinned down render mix which is splatted with harling towel at cob, or masonry wall in order to control suction for the scratch coat and to provide a key. It's an absolute must for cob but for internal work I am using BAUMIT DG27 PRIMER instead - it's a bit like blue grit for lime.
 

carys

Well-Known Member
Lots of new , fast, waterpoof materials turn out to be very damaging. Waterproof paints on wood have destroyed many a window frame.

Yeah, i know a harl coat as just a thinned down render mix which is splatted with harling towel at cob, or masonry wall in order to control suction for the scratch coat and to provide a key. It's an absolute must for cob but for internal work I am using BAUMIT DG27 PRIMER instead - it's a bit like blue grit for lime.
Only trouble whith this place stone got paint on it meshing going cost a fortune. Could try power washing it. Or hack joint make shoure paint is sound do you think the harl will hold to the painted stone. Or have you any ideas thanks m8
 
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