How do i make Lime mortar?
Discussion
I'm getting some confusing information as to how to make this stuff. Some sites or people say its just like cement so 1 hydraulic lime to 4 sand. Some say 4 sand, 1 lime and 1 Portland cement. I'm not sure! The wall is well over 100 years old too with hand made bricks so I need to get this right, any ideas?
If it's just a re-point and you don't need vast quantities buy it pre bagged.
http://www.lime-mortars.co.uk
http://www.lime-mortars.co.uk
For a wall of that age you'd want more lime than cement.
I'd suggest:
1 - cement/2 - lime/9 - Building / Sharp (Rendering)/ Thames washed (floor screed) sand
The choice of which sand will determine the look and colour of the completed joint.
For a smooth finish use building sand, for a rougher courser look use sharp sand, or a combination of Building and sharp sand, alternatively a combination of sharp and Thames washed.
I'd suggest:
1 - cement/2 - lime/9 - Building / Sharp (Rendering)/ Thames washed (floor screed) sand
The choice of which sand will determine the look and colour of the completed joint.
For a smooth finish use building sand, for a rougher courser look use sharp sand, or a combination of Building and sharp sand, alternatively a combination of sharp and Thames washed.
B17NNS said:
If it's just a re-point and you don't need vast quantities buy it pre bagged.
http://www.lime-mortars.co.uk
That would do the trick but I need a good amount. It's a long old wall 2 metres by 20, booth sides need doing and it's in a bad way http://www.lime-mortars.co.uk
Matt99man said:
That would do the trick but I need a good amount. It's a long old wall 2 metres by 20, booth sides need doing and it's in a bad way
Quite a lot then.Calculator on that site.
http://www.lime-mortars.co.uk/calculators/pointing
B17NNS said:
Matt99man said:
That would do the trick but I need a good amount. It's a long old wall 2 metres by 20, booth sides need doing and it's in a bad way
Quite a lot then.Calculator on that site.
http://www.lime-mortars.co.uk/calculators/pointing
£425.00!
Buy the material (big bag of sand + bags of lime/cement) at a Builders merchant and you'd be hard pushed to pay 25% of that.
Gauge the mix (whatever you run with) carefully, and buying it pre mixed/packaged would be madness.
I make my own.
Buy a large plastic tub - plastic dustbin would be fine.
you want goggles, gloves and possibly a respirator/face mask. Lime is not nice stuff in the raw form.
half fill tub with water and empty a sack of normal builders lime into it. take care to not get lots of lime in the air.
Stir.
some people put the bag in whole, slash the bag apart and remove the bag so that the initial mixing happens under water.
You want the lime to be fully covered by the water.
Put the lid on and leave for at least a week. Some people say months, but you can get away with quite a short time.
The lime will settle and form a thick putty - Lime putty. The longer you leave it the thicker it gets. If you use it quickly then it has lots of water in it and the mortar will be sloppy.
You can make a working mortar with between 3:1 and 5:1 sand:lime putty.
The sand used will make a big difference to the end colour. People are known to also add clay/soil/hair/unicorn horn/etc.
You can't tell the end colour from the wet colour - you need to allow a sample to set.
The mortar keeps for ages, just put in it an airtight tub. Lime putty keeps for years - just make sure that it has a layer of water over it.
Buy a large plastic tub - plastic dustbin would be fine.
you want goggles, gloves and possibly a respirator/face mask. Lime is not nice stuff in the raw form.
half fill tub with water and empty a sack of normal builders lime into it. take care to not get lots of lime in the air.
Stir.
some people put the bag in whole, slash the bag apart and remove the bag so that the initial mixing happens under water.
You want the lime to be fully covered by the water.
Put the lid on and leave for at least a week. Some people say months, but you can get away with quite a short time.
The lime will settle and form a thick putty - Lime putty. The longer you leave it the thicker it gets. If you use it quickly then it has lots of water in it and the mortar will be sloppy.
You can make a working mortar with between 3:1 and 5:1 sand:lime putty.
The sand used will make a big difference to the end colour. People are known to also add clay/soil/hair/unicorn horn/etc.
You can't tell the end colour from the wet colour - you need to allow a sample to set.
The mortar keeps for ages, just put in it an airtight tub. Lime putty keeps for years - just make sure that it has a layer of water over it.
Edited by TooLateForAName on Saturday 21st September 15:32
TooLateForAName said:
I make my own.
Buy a large plastic tub - plastic dustbin would be fine.
you want goggles, gloves and possibly a respirator/face mask. Lime is not nice stuff in the raw form.
half fill tub with water and empty a sack of normal builders lime into it. take care to not get lots of lime in the air.
Stir.
some people put the bag in whole, slash the bag apart and remove the bag so that the initial mixing happens under water.
You want the lime to be fully covered by the water.
Put the lid on and leave for at least a week. Some people say months, but you can get away with quite a short time.
The lime will settle and form a thick putty - Lime putty. The longer you leave it the thicker it gets. If you use it quickly then it has lots of water in it and the mortar will be sloppy.
You can make a working mortar with between 3:1 and 5:1 sand:lime putty.
The sand used will make a big difference to the end colour. People are known to also add clay/soil/hair/unicorn horn/etc.
You can't tell the end colour from the wet colour - you need to allow a sample to set.
The mortar keeps for ages, just put in it an airtight tub. Lime putty keeps for years - just make sure that it has a layer of water over it.
Are you anywhere in the South East? I've some Victorian brickwork which needs OPC raking out and re-pointing by someone who knows what they are doing. PM if so.Buy a large plastic tub - plastic dustbin would be fine.
you want goggles, gloves and possibly a respirator/face mask. Lime is not nice stuff in the raw form.
half fill tub with water and empty a sack of normal builders lime into it. take care to not get lots of lime in the air.
Stir.
some people put the bag in whole, slash the bag apart and remove the bag so that the initial mixing happens under water.
You want the lime to be fully covered by the water.
Put the lid on and leave for at least a week. Some people say months, but you can get away with quite a short time.
The lime will settle and form a thick putty - Lime putty. The longer you leave it the thicker it gets. If you use it quickly then it has lots of water in it and the mortar will be sloppy.
You can make a working mortar with between 3:1 and 5:1 sand:lime putty.
The sand used will make a big difference to the end colour. People are known to also add clay/soil/hair/unicorn horn/etc.
You can't tell the end colour from the wet colour - you need to allow a sample to set.
The mortar keeps for ages, just put in it an airtight tub. Lime putty keeps for years - just make sure that it has a layer of water over it.
Edited by TooLateForAName on Saturday 21st September 15:32
Not often that I'm accused of knowing what I'm doing 
Sorry - I'm in North Yorkshire and I'm only DIY. But living in a house built in the late 1700's I've spent a lot of time learning how to unbodge the efforts of previous owners and jobbing builders.
My house is a tip visually, but structurally it is in far better condition than it was.
Sorry - I'm in North Yorkshire and I'm only DIY. But living in a house built in the late 1700's I've spent a lot of time learning how to unbodge the efforts of previous owners and jobbing builders.
My house is a tip visually, but structurally it is in far better condition than it was.
Rats.
Here I have a coach house built in 1806 in the Gothic Revival style. It's brick with mortar render over, and never intended as a dwelling - moreover with two centuries of subsequent bodges.
However thank you very much for your illuminating post - at least I now know what to hassle the landlord to do.
Here I have a coach house built in 1806 in the Gothic Revival style. It's brick with mortar render over, and never intended as a dwelling - moreover with two centuries of subsequent bodges.
However thank you very much for your illuminating post - at least I now know what to hassle the landlord to do.
Matt99man said:
I'm finding it difficult to get the right lime for the mix. I'm going to do the dry mix as making the putty seems a little much for me! There's hydrated lime and hydraulic lime. Hydrated is the one I need (I think!) is it only builders merchants that sell it?
Jewsons sell Hydralime which is produced by Blue Circle.Most good Builders Merchants will carry hydrated lime.
No cement at all in lime mortar. Listen to those who understand old buildings http://www.spab.org.uk/
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