Thank you, all the way from a small town in Upstate New York, for taking the time to make these videos on a topic which has a general lack of available information, educational resources, and experts of both the technical and the practical regarding the historically appropriate and compatible mortar, plaster, etc. for restoring historic masonry structures. You are one of my new favorite historic masonry mentors! I have always been captivated and fascinated with masonry structures and materials, even as a small child helping my father lay tiles or mixing concrete. But, I took a different path and only returned to masonry at the age of 33, and now it's both my passion and my livelihood. Unfortunately, the current status, as it pertains to the building trades as whole, but, more specifically, to masonry, is saddening in the United States. The availiabity of both capable individuals to work and those with the knowledge and willingness to teach others are both incredibly scarce. All I had when I started on this path was some minor experience as a child helping my father with DIY projects (a concrete laborer, not a mason), two years of varied trade experience working for a childhood friend who is a general contractor (and, former union bricklayer), and a passion for masonry. I taught myself by reading books, watching TH-cam videos, and doing personal research. I was fresh out of prison and had nothing in the way of capital or a mentor. Through constant hard work, determination, extreme attention to detail, and pusing myself to the limits of my physical strength, endurance, and sanity I quickly became one of the areas best masons. Like the sand in the beginning of your video, I too am thirsty, only not for water, but for knowledge. After a couple years of mostly smaller projects, I was hired to repair a collapsing Victorian home built in 1890 and of all the mason's who gave them quotes, I was the ONLY one to recognize (or, probably even know) the masonry was historic lime based mortar and plaster and the need for using compatible materials in the repair. I have since made it a personal mission of mine to save whatever historic masonry I can before it is destroyed by natural deterioration or modern day American masons and their portland cement; or both. The following is an estimation based of my personal interaction with other contractors, suppliers of trade tools, materials, etc, and speaking with clients with historic masonry structures... as well as, being a first hand witness to dozens if not hundreds of examples of historic structures in utterly devastating condition after being "worked" on or "repaired" by other contractors/masons; but, the vast majority of Masons in America, regardless their specialty, location, or age, don't even know what lime mortar in the context of historic masonry is, let alone how to make or use it (they incorrectly believe lime mortar is the practice mortar made with hydrated lime and does not set, as this is literally what they are taught in trade schools and use for training purposes.) I have to drive 8 hours to get the hydraulic lime and natural sand aggregate I use and the supplier is one of literally only a handful in the entire USA. Knowledge of the subject, is just as hard to come by, and the results of this lack can be seen across America in the crumbling, unsightly, and dangerous (structurally) masonry structures of pre-1900. Most are either allowed to collapse (hopefully with no one in them!), exist in a state of unsightlyness and disrepair due to being repaired incessantly and incorrectly, or they undergo large scale repairs changing the structure to the point that they no longer can even be considered historic buildings. That is, unless you are wealthy enough to find and hire a company specializing in the restoration or preservation of historic masonry (usually there is one located in the biggest city of each state, I am one of three in the entire state of New York!) Which equates to 95 percent or so of the historic masonry structures outside of major cities being left to deterioratiate or repaired to devastation. Its saddening and frustrating. So, truly thank you!
The secret to Roman concrete is hot mix, some lime is left unslaked and when crack, inevitably, appear the un reacted lime (5-7mm pockets) meets with water and it heals the crack!!!
I think best practice is 1:3, so there is more free lime in the mix. Also I believe its good practice to state the binder then the aggregate proportion, so 1 to 3, not a 3 to 1 mix.
Many thanks for creating this video. It’s exactly what I needed to know. What is the aggregate this is used in the mix please? If I was to use this mix to do pointing do you think it’s best to cover the mix so it doesn’t dry out to quickly or would it be okay?Any help would be greatly appreciated. Thanks
Thank you. Based on my research the 1:3 lime to aggregate was misinterpreted in modern times, thinking that NHL or Hydrated lime could be used 1:3. In the old texts from hundreds of years ago, the 1:3 ratio always meant 1 part quicklime to 3 parts aggregate which changes the proportions to a 2:3 since it doubles in size. I think this is a major reason why hydrated lime fails. I think this is why you should stay with a 1:3 ratio of quicklime to aggregate and not a 1:5. Thanks for the video and I hope your project was a success.
That’s very true, Nigel Copsey states the same, he never did mentioned ratio 5:1, in old texts he encountered, it was 2:1, or even 1:1, but never leaner. This mix in video is utterly misleading and incorrect. On page 88, he says that after “…extensive testing, [it] was that two parts well-graded coarser sharp sand to one part finer sharp sand to one part quick lime represented the optimum aggregate component, suitably adopted when the proportion was 1:2”. Also there are also video tutorials that use 4:1, again very confusing. If they want to DIY people choose lime over cement, which I do in most cases, they must make up their mind and use uniform ratio sand and lime, also they shouldn’t not be secretly developing recipe for aggregates to be added to quick lime. I recommend, anyone who wants to use more environmentally friendly material, that had been used for last five thousand years, to read Nigel’s book, I at least learned a lot.
@@deninsrmic4165 In my experience the mixture should be adjusted for the application, out of necessity. I have used 2:1 and even 1:1 as a bedding mortar for bricks and stones. I have used 5:1 for pointing because that is what worked the best. The shrinkage with a 2:1 mixture would be terrible if used for pointing. This was with pure quicklime. People should do their own studies.
Would love to know how you do a large quantity of this on site? Also surprised you can touch it with your hands. How long do you have to work with this before going off?
To make a more durable mortar, one would add 10-15% of portland added at the end? Sounds like he is saying "potsland", but I don't know what that is. Great video by the way! The step-by-step explanation is very helpful.
Opc should never be mixed with natural lime. If your talking about hydrated lime or bag lime from builders merchants this is used as a replacement for plastisicer.
What is the aggregate this is used in the mix please? If I was to use this mix to do pointing on brickwork is there an average time limit on how quick it sets? Many thanks
How not to slake lime. The 15 minute volcano slake was a complete waste of time, you lost the heat because you didn't add enough water and then you just mixed it cold. Should have just made a second video and deleted this one.
![HOW TO MIX LIME MORTAR [Bricklaying for beginners e.p 6]](http://i.ytimg.com/vi/utrT3dMFkRM/mqdefault.jpg)
Thank you, all the way from a small town in Upstate New York, for taking the time to make these videos on a topic which has a general lack of available information, educational resources, and experts of both the technical and the practical regarding the historically appropriate and compatible mortar, plaster, etc. for restoring historic masonry structures. You are one of my new favorite historic masonry mentors! I have always been captivated and fascinated with masonry structures and materials, even as a small child helping my father lay tiles or mixing concrete. But, I took a different path and only returned to masonry at the age of 33, and now it's both my passion and my livelihood. Unfortunately, the current status, as it pertains to the building trades as whole, but, more specifically, to masonry, is saddening in the United States. The availiabity of both capable individuals to work and those with the knowledge and willingness to teach others are both incredibly scarce. All I had when I started on this path was some minor experience as a child helping my father with DIY projects (a concrete laborer, not a mason), two years of varied trade experience working for a childhood friend who is a general contractor (and, former union bricklayer), and a passion for masonry. I taught myself by reading books, watching TH-cam videos, and doing personal research. I was fresh out of prison and had nothing in the way of capital or a mentor. Through constant hard work, determination, extreme attention to detail, and pusing myself to the limits of my physical strength, endurance, and sanity I quickly became one of the areas best masons. Like the sand in the beginning of your video, I too am thirsty, only not for water, but for knowledge. After a couple years of mostly smaller projects, I was hired to repair a collapsing Victorian home built in 1890 and of all the mason's who gave them quotes, I was the ONLY one to recognize (or, probably even know) the masonry was historic lime based mortar and plaster and the need for using compatible materials in the repair. I have since made it a personal mission of mine to save whatever historic masonry I can before it is destroyed by natural deterioration or modern day American masons and their portland cement; or both. The following is an estimation based of my personal interaction with other contractors, suppliers of trade tools, materials, etc, and speaking with clients with historic masonry structures... as well as, being a first hand witness to dozens if not hundreds of examples of historic structures in utterly devastating condition after being "worked" on or "repaired" by other contractors/masons; but, the vast majority of Masons in America, regardless their specialty, location, or age, don't even know what lime mortar in the context of historic masonry is, let alone how to make or use it (they incorrectly believe lime mortar is the practice mortar made with hydrated lime and does not set, as this is literally what they are taught in trade schools and use for training purposes.) I have to drive 8 hours to get the hydraulic lime and natural sand aggregate I use and the supplier is one of literally only a handful in the entire USA. Knowledge of the subject, is just as hard to come by, and the results of this lack can be seen across America in the crumbling, unsightly, and dangerous (structurally) masonry structures of pre-1900. Most are either allowed to collapse (hopefully with no one in them!), exist in a state of unsightlyness and disrepair due to being repaired incessantly and incorrectly, or they undergo large scale repairs changing the structure to the point that they no longer can even be considered historic buildings. That is, unless you are wealthy enough to find and hire a company specializing in the restoration or preservation of historic masonry (usually there is one located in the biggest city of each state, I am one of three in the entire state of New York!) Which equates to 95 percent or so of the historic masonry structures outside of major cities being left to deterioratiate or repaired to devastation. Its saddening and frustrating. So, truly thank you!
Dude, you wrote a dang book!
@Xassaw and? I'm Italian, we are talkative, expressive, and cover every base! Is that a problem?
I had Tom as a lecturer at uni, very nice and knowledgeable bloke.
The secret to Roman concrete is hot mix, some lime is left unslaked and when crack, inevitably, appear the un reacted lime (5-7mm pockets) meets with water and it heals the crack!!!
Hence the self healing properties of lime mortar.Thanks.
I didn't know that.👍🏻
I always thought that Roman Soldiers came out at night to repair the cracks 😁
So adding pozzolans to this mix would immitate a lime and portland mix right?
I think best practice is 1:3, so there is more free lime in the mix. Also I believe its good practice to state the binder then the aggregate proportion, so 1 to 3, not a 3 to 1 mix.
Many thanks for creating this video. It’s exactly what I needed to know. What is the aggregate this is used in the mix please? If I was to use this mix to do pointing do you think it’s best to cover the mix so it doesn’t dry out to quickly or would it be okay?Any help would be greatly appreciated. Thanks
Good stuff Tom! Would like to see more of these great informative videos in the future.
Thank you Jamie- we hope to have more videos soon!
@@helenaburke2201 Good to hear, I missed Tom's calming voice...like listening to Attenborough!
Thank you. Based on my research the 1:3 lime to aggregate was misinterpreted in modern times, thinking that NHL or Hydrated lime could be used 1:3. In the old texts from hundreds of years ago, the 1:3 ratio always meant 1 part quicklime to 3 parts aggregate which changes the proportions to a 2:3 since it doubles in size. I think this is a major reason why hydrated lime fails. I think this is why you should stay with a 1:3 ratio of quicklime to aggregate and not a 1:5. Thanks for the video and I hope your project was a success.
That’s very true, Nigel Copsey states the same, he never did mentioned ratio 5:1, in old texts he encountered, it was 2:1, or even 1:1, but never leaner. This mix in video is utterly misleading and incorrect. On page 88, he says that after “…extensive testing, [it] was that two parts well-graded coarser sharp sand to one part finer sharp sand to one part quick lime represented the optimum aggregate component, suitably adopted when the proportion was 1:2”. Also there are also video tutorials that use 4:1, again very confusing. If they want to DIY people choose lime over cement, which I do in most cases, they must make up their mind and use uniform ratio sand and lime, also they shouldn’t not be secretly developing recipe for aggregates to be added to quick lime. I recommend, anyone who wants to use more environmentally friendly material, that had been used for last five thousand years, to read Nigel’s book, I at least learned a lot.
@@deninsrmic4165 In my experience the mixture should be adjusted for the application, out of necessity. I have used 2:1 and even 1:1 as a bedding mortar for bricks and stones. I have used 5:1 for pointing because that is what worked the best. The shrinkage with a 2:1 mixture would be terrible if used for pointing. This was with pure quicklime. People should do their own studies.
Seems like a huge energy investment for such a small mix, could this not be done in a cement mixer?
Yes, for bigger projects, there are mixing machines.
What is the hydraulic lime mix that will set by reacting with water, like cement does, and not by drying out with air?
Would love to know how you do a large quantity of this on site?
Also surprised you can touch it with your hands.
How long do you have to work with this before going off?
These two videos seem like short clips from some longer presentation. Where is the rest of the talk?
AWESOME JOB THANKS FOR SHARING
Great video.
Can I mix lime with soil, Clay?
They did used to, not sure with hot lime? Also used the coals from a site fire to colour the mortar too 👍
is it resilient to frost?
yup
Superb video, thank you!
Nice work Tom.
Very good explain, thank You.
the temperature of the process is in Farhenheit or Celsius ?
british accent take a guess
To make a more durable mortar, one would add 10-15% of portland added at the end? Sounds like he is saying "potsland", but I don't know what that is. Great video by the way! The step-by-step explanation is very helpful.
He was talking about POZOLAN, That is volcanic rock.
Opc should never be mixed with natural lime. If your talking about hydrated lime or bag lime from builders merchants this is used as a replacement for plastisicer.
Many thanks for creating this video. It’s exactly what I needed to know. Only thing is what is the aggregate this is used in the mix? Thanks
@@avfczoff well graded sand, so that’s sharp/grit sand along with finer plastering sand.
Don’t use just one building sand
@@alex1916v Great thanks 👍🏻 Really appreciate your help
Could this be really used for the purposes for which we use Hydroaulic lime or cement? Thanks
Wouldn't it be 2 and half aggregate and half lime? Not to 1.
Not having a dig im just clarifying.
Many thanks.
What is the aggregate this is used in the mix please? If I was to use this mix to do pointing on brickwork is there an average time limit on how quick it sets?
Many thanks
Probably sharp sand
How not to slake lime. The 15 minute volcano slake was a complete waste of time, you lost the heat because you didn't add enough water and then you just mixed it cold. Should have just made a second video and deleted this one.
👍
Not logical