Penners
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Geoff - I'm not sure whether "you" means thiambal or me, but I would certainly be very glad to have it, please.GeoffP said:
Many thanks.
- Thread starter thiambal
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Many thanks.
skier-hughes
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Geoff,
You could start a new thread and title it Lime Guide, to make it easy to search for and post it for all to get the benefit. I'm always interested in reading new info.
You could start a new thread and title it Lime Guide, to make it easy to search for and post it for all to get the benefit. I'm always interested in reading new info.
Nemesis
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Here's a start:
http://www.hullcc.gov.uk/pls/portal/docs/PAGE/HOME/PLANNING/CONSERVATION/LISTED%20BUILDINGS/LIME_POINTING.PDF
Please read!
If you used bagged hydrate and mix it with water it's non-hydraulic putty. You can buy non-hydraulic putty in tubs too, some think it is better quality to use. Others think it's just expensive...
You need to add an aggregate. Sand.
It cures in a different way to hydraulic, and in general is more permeable and therefore breathable.
You can add a pozzolan to it. That makes it cure more rapidly but can make it less breathable. It acts more like a weak hydraulic.
Hydraulic can be used too - but how and when varies from person to person and situation to situation. That comes in different 'strengths.' Rarely would you need to use the very strong ones. As it's a chemical set, once mixed with water, just like cement, it starts to harden. It comes dry in bags (like non-hydraulic hydrate) but you must mix and use it - it won't keep.
At this time of year, in non-exposed postions, putty (non-hydraulic), either home made or bought, used with care should be fine. However, for things like chimneys use a weak hydraulic.
Cover it with something if possible, don't allow it to get frosted, and spray it over a few times to keep it damp.
Then when it is hard enough but still 'green' you can rub it back a bit to expose the aggregate.
http://www.hullcc.gov.uk/pls/portal/docs/PAGE/HOME/PLANNING/CONSERVATION/LISTED%20BUILDINGS/LIME_POINTING.PDF
Please read!
If you used bagged hydrate and mix it with water it's non-hydraulic putty. You can buy non-hydraulic putty in tubs too, some think it is better quality to use. Others think it's just expensive...
You need to add an aggregate. Sand.
It cures in a different way to hydraulic, and in general is more permeable and therefore breathable.
You can add a pozzolan to it. That makes it cure more rapidly but can make it less breathable. It acts more like a weak hydraulic.
Hydraulic can be used too - but how and when varies from person to person and situation to situation. That comes in different 'strengths.' Rarely would you need to use the very strong ones. As it's a chemical set, once mixed with water, just like cement, it starts to harden. It comes dry in bags (like non-hydraulic hydrate) but you must mix and use it - it won't keep.
At this time of year, in non-exposed postions, putty (non-hydraulic), either home made or bought, used with care should be fine. However, for things like chimneys use a weak hydraulic.
Cover it with something if possible, don't allow it to get frosted, and spray it over a few times to keep it damp.
Then when it is hard enough but still 'green' you can rub it back a bit to expose the aggregate.
thiambal
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So non-hydraulic takes longer to go off, can be mixed and left and is more supply than hydraulic.
Hydraulic is more brittle but faster setting with a quicker chemical reaction a bit like cement.
So what makes non-hydraulic into hydraulic then? Or vice versa?
A Pozzolan is something which makes a non-hyrdaulic lime go off quicker but so quick as hydraulic.
So what is hydrated? Is there a non-hyrdated?
I thought that the pre-mized lime putty you could buy already had some sand in it? Certainly I was sold something a few years ago with Lime Putty printed on it and was told I could use if for patching up an area of plaster - worked a treat!
Finally, I am not sure if it is me but Nemesis's link did not work.
Hydraulic is more brittle but faster setting with a quicker chemical reaction a bit like cement.
So what makes non-hydraulic into hydraulic then? Or vice versa?
A Pozzolan is something which makes a non-hyrdaulic lime go off quicker but so quick as hydraulic.
So what is hydrated? Is there a non-hyrdated?
I thought that the pre-mized lime putty you could buy already had some sand in it? Certainly I was sold something a few years ago with Lime Putty printed on it and was told I could use if for patching up an area of plaster - worked a treat!
Finally, I am not sure if it is me but Nemesis's link did not work.
Jon Maine
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Lime putty is non hydraulic lime. Essentially as I understand it if you dry it before it carbonates and grind it into a powder this is hydrated lime (although it would seem to make sense if it were called de-hydrated). So if you add water to hydrated lime it returns to a state similar to putty lime.
Hydraulic lime is prepared differently, it is again cooked in a kiln although I am unsure of the entire process. It has I believe either clay or silicate impurities in it which depending upon the volume will cause it to set either more slowly to a set strength or rapidly. The term hydraulic refers to its ability to set below water I believe.
Pozzolans are very often ground up brick or volcanic ash which have a similar effect upon the lime as hydraulic creating an early set. However with all limes they will continue to carbonate after the initial set or in the case of pure putty lime it will only set upon carbonation.
Essentially the quicker the set the less breathable the mortar. We have no problems with breathability using a NHL2 or 3.5, it certainly lets out the moisture well enough although this would be improved by using putty.
In your instance with a garden wall breathability is not a major concern as long as the mortar is not soaking wet in frosty weather you should have no problems. It is however very important for walls of buildings to be breathable.
Lime putty mortars are available pre-mixed as sealed in a bag or lidded bucket they will not carbonate
Evs link worked for me, its a pdf file, do you have acrobat reader on your pc? Try this http://www.youtube.com/watch?v=jpxZ--fRdbo&feature=related
Hydraulic lime is prepared differently, it is again cooked in a kiln although I am unsure of the entire process. It has I believe either clay or silicate impurities in it which depending upon the volume will cause it to set either more slowly to a set strength or rapidly. The term hydraulic refers to its ability to set below water I believe.
Pozzolans are very often ground up brick or volcanic ash which have a similar effect upon the lime as hydraulic creating an early set. However with all limes they will continue to carbonate after the initial set or in the case of pure putty lime it will only set upon carbonation.
Essentially the quicker the set the less breathable the mortar. We have no problems with breathability using a NHL2 or 3.5, it certainly lets out the moisture well enough although this would be improved by using putty.
In your instance with a garden wall breathability is not a major concern as long as the mortar is not soaking wet in frosty weather you should have no problems. It is however very important for walls of buildings to be breathable.
Lime putty mortars are available pre-mixed as sealed in a bag or lidded bucket they will not carbonate
Evs link worked for me, its a pdf file, do you have acrobat reader on your pc? Try this http://www.youtube.com/watch?v=jpxZ--fRdbo&feature=related
jason.p
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This is the pointing tool I prefer to use. It's a ground down small plastering tool from screwfix, and can be made with two different width ends. Rather than use a hawk, I find it easier to hold a ball of mortar in one hand, and apply with the pointing tool with the other. It's best to make the mix fairly dry, and wear a glove!!
Nemesis
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Try the link again. If it still doesn't work - say so but I'm off to Embra first thing and won't be back until late so won't have time until Wed poss to fiddle with it.
http://www.hullcc.gov.uk/pls/portal/docs/PAGE/HOME/PLANNING/CONSERVATION/LISTED%20BUILDINGS/LIME_POINTING.PDF
Have also sent it to you via a PM.
Or try Hull County Council - Planning - Listed Buildings - Lime.
Site search on the Hull CC website - conservation lime.
Basically it's Jane Schofield's stuff.
You can buy non-hydraulic lime as putty or lime as putty ready mixed with aggregate, although this tends more to be used for plastering. Then yes you can buy dry hydrate (hydrated lime) which can be mixed into a non-hydraulic putty too. It's readily avaiable and not too expensive.
(Hydraulic, as Jon says, refers to the fact the stuff sets under water - like cement - so once mixed it needs to be used. It comes in bags dry. Non-hydraulic won't set until the slow carbonation process takes place. So the lime keeps when mixed and covered.)
Hydrate basically is stocked by yer average builders' merchant as it is used to mix with cement.
Buy it fresh and mix - don't leave the bag open and expect to use it again. It is not reliable that way. It will keep as putty though, use a cheap placcy bin.
A weak ('feebly') hydraulic is OK to use either, but 'conservation' best practice tends to go for non-hydraulic as the fall-back position. However, there are times and places and building materials where a hydraulic will be useful. But I think that for a beginner I'd go for the basic non-hydraulic.
http://www.hullcc.gov.uk/pls/portal/docs/PAGE/HOME/PLANNING/CONSERVATION/LISTED%20BUILDINGS/LIME_POINTING.PDF
Have also sent it to you via a PM.
Or try Hull County Council - Planning - Listed Buildings - Lime.
Site search on the Hull CC website - conservation lime.
Basically it's Jane Schofield's stuff.
You can buy non-hydraulic lime as putty or lime as putty ready mixed with aggregate, although this tends more to be used for plastering. Then yes you can buy dry hydrate (hydrated lime) which can be mixed into a non-hydraulic putty too. It's readily avaiable and not too expensive.
(Hydraulic, as Jon says, refers to the fact the stuff sets under water - like cement - so once mixed it needs to be used. It comes in bags dry. Non-hydraulic won't set until the slow carbonation process takes place. So the lime keeps when mixed and covered.)
Hydrate basically is stocked by yer average builders' merchant as it is used to mix with cement.
Buy it fresh and mix - don't leave the bag open and expect to use it again. It is not reliable that way. It will keep as putty though, use a cheap placcy bin.
A weak ('feebly') hydraulic is OK to use either, but 'conservation' best practice tends to go for non-hydraulic as the fall-back position. However, there are times and places and building materials where a hydraulic will be useful. But I think that for a beginner I'd go for the basic non-hydraulic.
Hello
Now I am a little confused however you can buy ready mixed lime product from http://www.mikewye.co.uk
However as it is a wall you are making good, and im not sure if you said it was dressed with lime, I have an easy alternative for laying and pointing:
5 parts red builders sand, 1 part cement, 1part hydrated lime from builders supplier and water to mix into the right consistancy.
Now I am a little confused however you can buy ready mixed lime product from http://www.mikewye.co.uk
However as it is a wall you are making good, and im not sure if you said it was dressed with lime, I have an easy alternative for laying and pointing:
5 parts red builders sand, 1 part cement, 1part hydrated lime from builders supplier and water to mix into the right consistancy.
Nemesis
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No - NO CEMENT AT ALL!
It could ruin the wall in the short or long term. Not too great for the environment either of course.
Use only lime and aggregate, either ready mixed or DIY. A bit of earth as Biff suggests won't do any harm.
See:
http://www.periodpropertyshop.co.uk/acatalog/Plasters_and_Mortars.html
http://periodproperty.co.uk/forum/viewtopic.php?f=1&t=8882&st=0&sk=t&sd=a&hilit=cement
It could ruin the wall in the short or long term. Not too great for the environment either of course.
Use only lime and aggregate, either ready mixed or DIY. A bit of earth as Biff suggests won't do any harm.
See:
http://www.periodpropertyshop.co.uk/acatalog/Plasters_and_Mortars.html
http://periodproperty.co.uk/forum/viewtopic.php?f=1&t=8882&st=0&sk=t&sd=a&hilit=cement
biffvernon
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thiambal said:
I still think the wine analogy is good. You can read thousands of books, spend zillions of pounds and wax lyrical with adjectives conceived for quite different purposes.
Or you can go to the nearest supermarket and grab a couple of bottles of whatever is in the bin by the door. I can't usually tell the difference.
If you buy a bag of 'lime' from the nearest builders merchant and pretend it is cement it works just fine. Mix it dry, one part of the dry white powder and three parts of sand as dirty as you like (I fish the larger leaves and twigs out), add water to taste as use straight away. I can't usually tell the difference.
Unlike cement, if you add too much water it doesn't matter - just leave it overnight and then pour off the water that has settled out on top.
Unlike cement, if you've made too much and don't use it all, stick it in a container and add an inch or two of water to cover it. It will keep forever.
From the "Teach Yourself Building" Series, "Brickwork" by E.L Braley, English Universities Press 1944. (A very systematic and thorough book - it starts with a formal definition of a brick)
- My grandfather was Clerk of Works on an estate, succeeded in the job by my uncle, so I have a number of similarly useful books -
"The simplest way to make mortar is to place three or four barrowloads of sand on a mixing board or stage, or on some good hard ground, and arrange the material so that the centre is left open. Next, take a half-hundredweight of hydrated lime and soak the lime in a barrel containing three parts of water, so that the lime and water form the consistency of cream when properly mixed. Into the hole in the centre of the heap of sand pour the fluid lime."
It goes on to describe mixing, how it can be left "a considerable length of time before being retempered", the possibility of "gauging" with a little cement sometimes to "accelerate the setting power", using hydraulic lime, and also making mortar with fresh lump lime. However, for simplicity, Biff's method seems to be confirmed, though I have found that the soaking in water first greatly adds to the ease of getting a good mix without little lumps of unmixed lime.
- My grandfather was Clerk of Works on an estate, succeeded in the job by my uncle, so I have a number of similarly useful books -
"The simplest way to make mortar is to place three or four barrowloads of sand on a mixing board or stage, or on some good hard ground, and arrange the material so that the centre is left open. Next, take a half-hundredweight of hydrated lime and soak the lime in a barrel containing three parts of water, so that the lime and water form the consistency of cream when properly mixed. Into the hole in the centre of the heap of sand pour the fluid lime."
It goes on to describe mixing, how it can be left "a considerable length of time before being retempered", the possibility of "gauging" with a little cement sometimes to "accelerate the setting power", using hydraulic lime, and also making mortar with fresh lump lime. However, for simplicity, Biff's method seems to be confirmed, though I have found that the soaking in water first greatly adds to the ease of getting a good mix without little lumps of unmixed lime.
Penners
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The link worked OK for me (even though it goes to somewhere oop north). A very useful leaflet.
Flyfisher
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Biff's approach seems intuitively right to me. The modern obsession with scientific standards and precision (e.g. washed sand graded to precise specifications) seems at odds with the likely practices of hundreds of years ago where building materials would have surely been sourced as locally as possible instead of being transported all around the country, or worse still, the world. And what could be more local than digging the required sand on site - impurities and all?
thiambal
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Jon, good YouTube link - although the work was a little on the messy side - would not the face of the stones become stained with lime where the mortar had touched it.
Nemesis, cheers for re-sending the link, my computer was obviously having a senior moment.
I think I am starting to get a basic understanding of the different types of lime - still not an idea what NHL 3.5 NLH 5 etc means.
Biff, chuck it all together and stick it in the wall, now that is a technique I can understand!!
As for digging local sand on site - how does lime react to a few shovel fulls of claggy clay?
Nemesis, cheers for re-sending the link, my computer was obviously having a senior moment.
I think I am starting to get a basic understanding of the different types of lime - still not an idea what NHL 3.5 NLH 5 etc means.
Biff, chuck it all together and stick it in the wall, now that is a technique I can understand!!
As for digging local sand on site - how does lime react to a few shovel fulls of claggy clay?
Flyfisher
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Ah well, fair point, but if you don't have any local sand then perhaps you're not using the 'appropriate' building materials in the first place :wink:thiambal said:
We have a large pit behind our house where, allegedly, the chalk was dug up for our C18 clunch extension and our soil is quite sandy. There is also an almost complete absence of oak trees, so I guess they went into the timber-framed part of the house
. It's just a shame that cement became a local commodity by the time the outside was re-rendered though :evil:
biffvernon
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Yes, that's very true - except that allowing little lumps of unmixed lime remain makes the pointing look nicer!piper said:
Jon Maine
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I agree, as long as its not unreacted to cause pot marks.
Penners
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Our first old house was a 15th century timberframe Essex cottage. Over the centuries the building had moved and twisted considerably, so there wasn't a straight line or a right-angle anywhere in it (luvverly!).Flyfisher said:
When we'd finished our repair work on it, just for a laugh we got a well-known kitchen company to come in and quote. Their "consultant" (Salesman? Oh dear me, no!) spent about 45 minutes measuring up and then declared that he'd found some major problems. I asked him what they were, and he replied, "Well, you've got a non-standard house here, you see."
:roll:
GeoffP
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Hi Skier,
I don't think I'd be any good at that, I'm not really a lime purist. My stone house has been standing for about 200 years in spite of its cement pointing ....... although when I re-point it, I will take note of the experts and use lime.
Geoff
thiambal
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Right, so if mixing up a large quantity of lime (say in the recommended old bin) is it better to stick water into the lime or lime into water? If it is the latter what proportion of water to lime approximately?