NHL, lime putty or quicklime??

Which lime to use and why.
A short video about the different natural hydraulic limes and why some NHL can
be the better choice over lime putty.

[@Southpoint2019]

I am now subscribed. Love these videos

[@angeladresler1855]

Just found your channel, very informative as I am now trying lime mortaring for the first time on my old school house 1855 so the bricks are soft reds and quite soft, I am off to try to get as neat and tidy as you do, thank you.

[@michaeljamesdesign]

Well done Angela, keep up the good work and let us know how you get on.

[@grantduncan7301]

Thank you Michael . So i reckon im looking for a lime with good strength and plenty of free lime content. That would appear to be a good compromise for my situation.

[@Mrwesmrwes]

Thank you for making this video!

[@EastyUK]

The states, we do sounds like that. Well maybe not me, I'm from Lancashire. Thanks of the video mate, great to hear more angles on the Lime universe. Its tough to get Hydraulic lime or NHL in the US, pretty price to ship, I've been using Hydrated lime and a pozzolan(metakoalin) that seems to be working well for various uses. I have a dustbin of hydrate lime putty for mortars, If you don't putty this stuff it will suck any water in the mix with hydrated it does crumble. For hempcrete I've been using powder with metaKaolin as you want it to dry fast through a 12 inch wall.

[@michaeljamesdesign]

Yes, faster drying hempcrete and hemp lime is always more convenient.

[@mainstreampropaganda7518]

very helpful... in my parts, they don't even sell lime mortar with a NHL content on the label... unbelievable how they hold us in check

[@TheJosepi87]

hi Micheal, i am going through Nigel Copseys book after your recommendation and its quite astonishing how little i knew about limes after working with them day in day out for so long and also how im not quite using the material i thought i was using! i went to have a look at a fireplace repoint/repair today and was instantly able to recognise it was an earth lime mortar rendered over with an unbelievably strong sand cement mortar. i think my plan of attack will be to repoint in a pozzolanic hot mix at a 1 to 3 ratio (quicklime). but i do have a question more out of curiosity than anything else, which is, is there a place for hydraulic quicklime or would you just go to the NHL's if a hydraulic set was desired? thanks for these videos, i would not of known about any of this without it 👍

[@michaeljamesdesign]

I use CL80.

[@bigjmal]

Thanks for this…I’ve got a small project in the highlands I was hoping to point this year, but we’re already getting some pretty hard frosts. I might try a sample section with quicklime…

[@michaeljamesdesign]

As long as it's case hardened then it should be OK. We sometimes get frost damage months after the work's been done.

[@38Highbury]

I find the same, it's unpredictable. Depends on the type if stone too. Makes me wonder what's best if a big job could all fail..who's going to pay to put it right??

[@grantduncan7301]

I find your content very informative and i have learned much about lime. I stay in the highlands of scotland where we have extreme winters. I have an old period property built of very hard red sandstone built in 1843. Im looking for a bit of guidance on what to have it pointed with . What you said in the video rings true....otterbein nhl 3.5 , after 12 month 10.5 N/nn compressive strength. St asteir NHL 5 after 24 months 7.8 N/nn commpressive strength ...3 to 1 mix. Im confused to what strength i should be using.

[@michaeljamesdesign]

It's horses for courses. This particular property is in Oxfordshire where we have mild weather in comparison to yours. Otterbein sounds like it would be fine for your environment.

[@grantduncan7301]

@@michaeljamesdesign Thank you. The otterbein 3.5 has a harder strength than the st asteirs 5. Thats where im confused .

[@michaeljamesdesign]

@@grantduncan7301 Otterbein Calcidur (3.5) has a free lime content of 32 and a compressive strength of 10.5. In comparison, St A NHL5 has around 15 - 20 available lime and a compressive strength of almost 9 at 1:2.5. This means that Otterbein wins as far as free lime content is concerned as it's far higher than St A. The St A has pretty much the same compressive strength but less lime. So it depends on what you want out of a lime. It depends on what your priorities are. More available lime means the Otterbein is the choice for pointing and plastering as it'll be more workable and will be more porous. And the Otterbein will look better because it isn't packed full of impurities. It's all about comparing and contrasting the virtues of the different NHLs. Never accept one at face value.

[@sealionbrian]

Hi, thanks for all the info in this video! I have an old basement that i need to redo the mortar in a few areas, the stones are limestone and in my area the limestone is supposedly very soft. A couple spots look like this exterior wall however most of the work I need to do isn't as deep as shown and I am not building anything. If I understand you correctly, NHL 3.5 can potentially be too strong - Should I be looking at getting a NHL 2.0 mix then? The basement is typically dry with the dehumidifier running and the winters can get pretty cold here (if that matters for interior) although I can heat the basement in winter. Thank you if you get a chance to answer!

[@michaeljamesdesign]

All NHLs are different. Some 2s are close the 3.5s and vice versa. I'd really have to have a look at the job before I could make a judgement call. But if it were me, and I'm not giving advice here, I'd use 2. But I would choose it very carefully and make sure it had the right free lime content and compressive strength for its purpose. Suitable ratios and aggregate choice would feature highly on my list as well.

[@as3cs3]

@@michaeljamesdesign this is all very confusing. let's dissect what you have written: 'All NHLs are different' makes no sense. I think what you mean is the NHL rating stamped on the packing is not accurate. 'Some 2s are close the 3.5s and vice versa' how do you know this? are you saying a product packaged as 3.5 can be more like 2? so what is the rating of that company's 2?. 'I'd really have to have a look at the job before I could make a judgement call. But if it were me, and I'm not giving advice here, I'd use 2.' you are giving advice. you are making videos telling people that all the available mortars are incorrectly-packaged regarding their NHL-spec then backing-out when someone, like Brian, asks for some clarity 'But I would choose it very carefully and make sure it had the right free lime content and compressive strength for its purpose' really? where would someone get this information? there's nothing on the packaging of my Secil 3.5 telling me the free lime content or compressive strength (other than 3.5 which you say it not of any use ) so where do you get that info?. 'Suitable ratios and aggregate choice would feature highly on my list as well' the suitable ratios and aggregate choice wouldn't be of much use if the binder (lime) was no good which you say Secil, St Astier and another one beginning with O are. 🤔🤔🤔🤔🤔🤔

[@plasterking]

Great video i have been lime plastering since the 80s and in Europe using machines plastering if you listen carefully mike tells you which lime to use because he listed which ones he was not using in Europe on clay blocks we used premixed lime and lime skim plaster because the walls were weak

[@oliverandrews2446]

Hello, thank you for posting these enlightening videos. Over the last few weeks I've been attempting to repoint a Victorian red brick garden wall with NHL 2 (Secil - yes, I know, but I didn't when I began...). I'm mixing this up in a ratio of 1:2.5 and it seems to have set well. One thing I'm not clear about though is the shelf life of opened NHL powder: some websites say two to three days at most. I've been mixing up small batches from the same bag over a longer period. Is it obvious when the powder should no longer be used (for example, will it be clumpy), or will it partially set resulting in a weaker mortar that'll fail during its first winter?

[@michaeljamesdesign]

Hi Oliver. Secil NHL2 certainly isn't the worst lime. It's got a decent free lime content and I'm happy using it for walling at its compressive strength is higher than some 3.5s. You don't want it too weak otherwise there's the possibility of frost damage whilst it's carbonating. Please feel suitably commended. I shall be using the same for a low garden wall myself in a couple of weeks and it was purchased back in 2019. I think there're many old wives tales about opened bags of NHL or NHL when it gets old. Many of these tales can be discarded as pure hokum. As long as you've kept your lime dry it's fine. Even if it gets a bit lumpy because it's been exposed to some moisture then just sieve out and get on with it. Some may disagree but I've never had any problems. Ever.

[@oliverandrews2446]

@@michaeljamesdesign In that case I'll rest easy. Glad to hear the Secil is appropriate for this application too; at the time it was a toss up between NHL2 and NHL3.5. I did worry that NHL2 would be too soft but I've since learnt that Secil is more cementitious than other limes and I'm glad I avoided 3.5 (more by luck than judgement). Anyway, thanks for your help and I look forward to more videos from you -- I'm very much enjoying using lime mortar and learning more about it.

[@xl5006]

ive reused 200 year old lime mortar saved from old walls and buildings, better than stuff you can buy today, this is only when theres plenty left to use, otherwise i use 3.5. also in cold weather i put couple of shovels of old mortar in the mix if i have some to send it off bit quicker, or some powdered chalk, i have been working as a flintknapper for about 30 years

[@rollingsculpture2413]

Love your videos Mike but don't mystify using lime to much otherwise you'll put people off and they will just carry on using cement.

[@michaeljamesdesign]

Not if they're listed buildings they won't. They can use whatever they like on anything else.

[@rollingsculpture2413]

@@michaeljamesdesign I live in a 200 year old cottage that's not listed and I care! To be honest with you in my area listing does absolutely nothing other than preventing a building from being knocked down. There's a chapel up the road from me that's listed and it's just had cement slapped all over it. Thanks for getting back to me and keep up the good work Mike.

[@as3cs3]

well said. he spends most of the video making negative observations but gives virtually no solutions

[@richardgrimbleby7853]

​@@as3cs3 very true is he a wanna be wizard

[@plummetplum]

Oh bugger I just bought a 25kg bag of Hanson NHL 3.5 to practice some tuck pointing on my house. You are the second person who I spoke to on KZbin who wouldn't recommend Hanson as well. It's a learning curve. I appreciate that you aren't going to say which brands to buy, but could you help by saying what I should be looking for to help guide my purchase. So for example free lime content above a certain threshold etc thx

[@michaeljamesdesign]

Chalkdown lime for some LaFarge 3.5 Nathural. Free lime rate: 44%

[@paultant6741]

Using hydrated lime to point a stone house in the west of Ireland at the minute. 1lime and 2 concrete sand which is very gritty. Is this ok as getting confused with watching videos

[@michaeljamesdesign]

Hey Paul, lime hydrate, for lack of a decent in depth explanation, is regarded as a lesser lime. Nevertheless, it was used prolifically back in the day. It has a very high free lime content and a low compressive strength which is great. However, it becomes inert if it isn't used fresh and is mainly used as a plasticiser for cement mortars. You'll be fine with it and it sounds like you have a nice sand to use. And you're mixing it at the correct ratio. The lime hydrate in the States is better than that what we have over this side of the pond but there's no reason you can't steam ahead with your project. But it might be worth thinking about adding a pozzolan to yours to give it a bit of early strength which would help it through its first winter.

[@paultant6741]

Thanks for quick reply. More confident now. Winters here are fairly mild. But will look into pozzolon.

[@deribrown]

What pozzolan do you use? I’ve only ever used trass but want to experiment with possibly adding an nhl lime in the mix.

[@michaeljamesdesign]

I try not to add NHL as it can mess with the setting processes. I only use it if I've got some lying around that I don't want. Trass is good but you can't use too much. The right amount is essential. Wood ash is difficult to find, metakaolin isn't ideal because it's expensive.

[@rosslukeshay]

Hi Mike, could you use fire ash from your own home ( ie timber & coal grounded down ) as a pozzolan

[@benllewellyn1887]

​@rosslukeshay yes.

[@towerdave4836]

Mixing ; by weight or volume? I’ve seen recommendations for both on KZbin . I’ve always mixed by volume.

[@michaeljamesdesign]

Always by volume.

[@maxcrooks2593]

Lafarge my favourite NHL I like to rework it a day before to reduce strength further

[@michaeljamesdesign]

You, are the man. Those who know, know.

[@shervinmokthari1251]

Thank you kings 🙏❤️

[@mw1460]

Hi, hot lime means not hydrated lime with sand and water or hydrated lime / slaked lime with sand? I don’t find any formula for hot lime.

[@michaeljamesdesign]

Slaked lime with sand.

[@thewinchesters8751]

Hi Michael. Does NHL 3.5 have to get added with sand or not for laying reclaimed quarry tiles? Thanks

[@michaeljamesdesign]

Yes

[@thewinchesters8751]

@@michaeljamesdesign what would you suggest to use for 're grouting all of the tiles once done thanks

[@michaeljamesdesign]

@@thewinchesters8751 Speak to Declan at Chalkdown Lime.

[@devugadhvi9629]

What should I use for my new house build? Cement or lime?

[@michaeljamesdesign]

Email me your architect's proposal and a complete set of plans with a proposed schedule or works and I'll let you know.

[@anthnymalclmrberts3847]

Very good info .iv done a couple of jobs .nhl 3.5lime mortar and french lime

[@michaeljamesdesign]

Ah, but was it the right French lime!

[@anthnymalclmrberts3847]

We built a extension using reclaimed bricks with french lime mortar in long melford just out Sudbury in in sufolk back in 2005 .it was a good job with my old boss. Then jointed up with a old broom handle.

[@michaeljamesdesign]

@@anthnymalclmrberts3847 I get what you’re saying but what kind of lime was it. I understand you used French like but there are a number of these.

[@anthnymalclmrberts3847]

i cant remember. It was that long time ago

[@anthnymalclmrberts3847]

If i vaguely remember we mix it a 3 sharp sand .3 soft sand 1 french lime. The french lime .i cant rember what it was called

[@grantduncan7301]

. Maybe worth speaking to masons mortar who have 3 branches in scotland . They used to stock lafarge with its big free lime content but stopped selling it.

[@michaeljamesdesign]

I'm not sure I follow. Are you suggesting I contact them?

[@adammapletoft6334]

Hi MIchael, bit confused when you say you'd use an NHL 2 but only one with a high compressive strength. Aren't you using Otterbein CL80 quicklime which has a higher lime content but a much lower compressive strength than say St Astier NHL 2? To give you some background, I'm repointing my red brick Victorian property c1890 and am thinking St Astier 2 but I notice from other videos of yours that you recommend using St Astier NHL 2 internally and Otterbein CL80 to do the external repointing. Any help is much appreciated.

[@adammapletoft6334]

FYI I'm also rebuilding the bay window so I was thinking Otterbein NHL 3.5 using a 1:3 mix of lime to course grained sharp sand.

[@michaeljamesdesign]

Hello Adam, you have to be a bit careful with NHL2 as some are low compressive strength and some are high. Same for free lime content. St Astier has loads of available lime (probably the highest free lime content available). But it'll still be lower than quicklime. So if you're going to build then I wouldn't recommend St A unless it was a 3.5. The Otterbein is difficult to get in the UK so if you're going to use a hot mix then I'd just go with Calbux and there's no issue with supply. But you'd need a pozzolan. Maybe a bit of wood ash or perhaps some trass. For red brick Victorian then you should be fine with St Astier NHL2 as long as it's not overlooking the sea or on top of a weatherprone hill. NHL gains strength over time. Colour is an issue though as it tends to dry really creamy white. If you want something a little less in your face than I find Secil NHL2 is lovely. Very workable. I like to use it 1:2.5. Any questions then just follow up.

[@adammapletoft6334]

Thanks Michael, very helpful. I do have one complication, and that is that I own the ground floor flat and so I'm only repointing a third of the building (the other flat owners didn't want to repoint at the same time as me), so I need to try to match the colour of their mortar which is unfortunately sand and cement, which is why I'm raking it out and getting it done property with lime. I think the Lime Centre has a colour matching service and I'm just wondering whether you have any experience of colour matching mortar? The other issue I have is that we've removed a concrete plinth surrounding the building and have discovered that the slate DPC has been drilled through in the distant past by a damp wally. I've had some gravimetric testing done of the brick just above the DPC to see if it's still doing it's job, and in the most part it is, with only slightly elevated levels, so I don't think we're going to resort to chopping out bricks and installing a new physical DPC. But I would like to fill the holes in the brick. This is obviously brick and not mortar so I guess it should be something with a high compressive strength, so an NHL 3.5 with a 1:2 mix I'm thinking? I guess I can go for and NHL with a high compressive strength and not necessarily a high lime content because we're talking about adding strength to the damaged brick rather than mortar. Thanks again.

[@michaeljamesdesign]

@@adammapletoft6334 I often us Masons Mortar for brick and stone repair products. You'll never get an NHL to match a cement mortar. The only thing you could do is introduce pigments but they have to be lime stable. Lamp black will darken down any lime mortar. Or you could use Ionic Old White NHL3.5. Standard free lime content unfortunately but it's the greyest on the NHL colour spectrum. You could use fireplace soot but that's pretty difficult to get hold of nowadays. And difficult to gauge. Hence the recommendation for Ionic Old White. As it's meant to re-create the look of a slightly polution stained brick mortar. Hope this helps.

[@adammapletoft6334]

Hi Michael, I’ve been looking into the colour matching a bit more, and I think I’m just going to follow your recommendation of Secil NHL 2, which by the looks of things has a greyer tone and should come close. Thanks, Adam

[@Offensiveword]

I’m pointing with lime and I can only find hydrated lime … is it gunna work ?

[@michaeljamesdesign]

You can only find hydrated lime because all you've done is gone down your local builder's mechant's Am I right? You need to mail order the right lime from a specialist supplier. Hydrate will work but t it must be fresh out of the factory gates, not left around open for days on end. Once open, use within a couple of days and throw away. If there's any left at the end of the week then bin it. Mix 1:3.

[@JustTis]

What if your lime putty isn’t half water and is a nice slacked lime/agg mix that’s been left to cure a bit? Would you still have an nhl preference for this work? Mind, I would mix a small amount of NHL with this..

[@michaeljamesdesign]

You'll have to disclose your lime to sand ratio otherwise I can't offer an opinion.

[@JustTis]

@@michaeljamesdesign mmm probably 5/6 to 1 depending on scenario? And then 1 shovel of nhl to a whole mix? I mean I’m working for a company at the moment so it’s not me or my works but I am learning and experimenting etc

[@michaeljamesdesign]

@@JustTis Always specify binder first. So in your case it would be 2:5/6?

[@as3cs3]

that's what I was thinking @Just Tis. He says it as if the putty HAS to be half water. Your pint is valid and he comes back with a stupid response about the lime to sand ratio instead of answering your point. must be all those years working as a psychology teacher 😂😂

[@matthemason7918]

Interesting about the NHL’s I didn’t know that. What you can do is mix nhl with lime and with the lime water as long as it’s settled ie. clear spray it on the wall as this is the only way I’d recommend to slow down the decay of the lime stone. Personally I make all my mortar using quick lime and a well graded washed sand best practice is to use an engineered sand. I sand slake for those reading this hot mix that’s gone cold then put into buckets and left for months. Also not all quick lime is the same as limestone is very different from quarry to quarry sometimes what part of the same quarry. Lime is touchy feely if it feels right/nice on the trowel it will work for you. Note. The more water in your mix the more water that needs to come out and that leads to cracks. Sorry if there are any spelling mistakes 🎓

[@ricdavid7476]

I moved into a victorian cottage just over a year ago, it is called lime cottage. It needed repointing and as i am retired and not well off i thought i would study up on the subject as i knew nothing about lime or re pointing. I watched a lot of your videos and got nigel copseys book on your recomendation although it was a bit heavy going. I shopped around for a lime supplier and upon your recomendation i landed on Chalk down lime. I explained what i needed and that i was a novice and asked them what they recomended and they recomended cecil tek 3.5 NHL. Over the summer i bought about £1000 of this ghastly stuff i kept on having to go back to them to buy more of the junk and each time they were happy to sell me more. By the end of an exhausting summer the end result was terrible i had half a house with the lovely original soft lime mortar and the other half with this rubbish. i lime washed the building afterwards and it just made the cecil tek stand out more. I then came across another of your videos in which you said that you should not use any supplier who supplies cecil tek 3.5 while in another video singing the praises of chalk down lime. I have now bought a good supply of non hydrolic ready mixed mortar and have started the exhausting labour of hacking out the year old cecil tek that has set as hard as any concrete i have seen. You need to warn people against chalk down lime rather than promote them or be more consistent in your videos. Listening to you and chalk down lime has wasted a year + of my life and a not inconsiderable amount of money.

[@michaeljamesdesign]

Hi David, Chalk Down Lime do indeed advertise Secil Tek premixed dry bagged mortar and as you had no experience they've obviously recommended it to you. I would never recommend that anyone should use a premixed dry bagged NHL3.5 mortar as they're about as far removed from traditional mortar as it's possible to get and they tend to set very hard. I learned my lesson long ago when I bought some from the Old House Store. Cost me a fortune and it was only to do a fireplace. But this is the hard earned and costly experience that us pros have to build up as we go through our working lives. Dry bagged premix tends to be expensive because you're paying a factory to source the materials and combine them but you're paying mostly for the sand. I must add though, that it is actually possible to achieve a good finish with a pre-mix. However, if Chalk Down Lime have suggested you use this product then that's their responsibility and I can't be held responsible for their recommendations or your choices. What I would always suggest though, is that a novice or a professional does a square metre to see what it looks like and if they're pleased with the product and their own ability then there's nothing stopping them going ahead. I'm surprised you did your whole house before the disappointment set in. This is, I'm afraid, your house and your rules. I can't stop people doing what they want on their own properties. I'm not responsible for the fact that you've had a go a lime pointing yourself and it hasn't come out well. I hate to say it but a good conservation mortar specialist can make just about any mortar look good. It's what we get paid for. Chalk Down Lime stocks some very good NHL and excellent putty. Either of these, and a bit of clean sand, is all anyone ever needs. But it takes years to get good at pointing with lime. I've been doing it nearly two decades and I'm still honing my skills. What you've now got is some of your very own experience. Costly yes, but it's just a start. It honestly takes years of being out in all weathers. Chalk it up to experience and keep on learning. But whether you do it yourself or pay someone to do it for you it will cost you something in some way at some point. You've learnt a hard lesson but all of us who are self employed have done the same. And it never stops. As a point of information, Chalk Down Lime no longer advertise Secil NHL3.5 on their website.

[@ricdavid7476]

@@michaeljamesdesign Hello Mr James thank you for the courtesy of a reply. If i could have afforded to get someone in to do the pointing i would have done but i am old now and live off a pretty small pension so could not. Yes you are right it is all down to experience and i have learned a lot in a year and still love lime and look at pointing and stonework wherever i go now. I hired a van and went down to dorset to Rose of Jericho to buy the non hydraulic lime mortar earlier this week and it was wonderfull going through towns like dorchester to see so much lime everywhere. Lime is something i was completely unaware of as a building material till about a year ago. I have only done half the house with cecil tec fortunately the remainder appears to be the original soft lime mortar and the difference between the 2 halves is very apparent. I am hacking out the cecil tec now and it is hard work. I wrote my comment to you ( and an e mail to chalk down lime ) after a long hard day in the sun today hacking this stuff out and as my head boiled i was thinking about who to blame other than myself whereas you are right it is my house and i made the decision but i cannot for the life of me think why chalk down lime made the recomendation they did. Anyhow its good to see that you are still hard at it. If you ever tired of the cotswolds there would be a lot of work for you in Dorset is should think

[@michaeljamesdesign]

@@ricdavid7476 Rose of Jericho do top gear. Really good.

[@ricdavid7476]

@@michaeljamesdesign Yes and they are happy to share their expertise with people and not just chase after a sale. Sadly this was not my experience with chalk down lime they could not get you off the phone quick enough and while i understand that time is money and these operations are businesses the ethos behind Rose of Jericho seems to be completely different they seem to be genuinely interested in their products and their customers.

[@michaeljamesdesign]

@@ricdavid7476 Yep, absolutely agree. All the suppliers have their virtues and their, shall we say, less attractive characteristics. There are some I hate to use but they have what I want so I'm bound. To be honest I buy from nearly all of them but Declan at Chalk Down Lime has the right NHL and the right quicklime at the right price. They're all mega busy at this time of year so I try to order online when and where I can. Nevertheless, even that has its disadvantage. But thanks for reminding me about Rose of Jericho as I need to place an order there myself.

[@tablettwentytwo1750]

Can I ask a question? Sweated tears over your own, (and others) videos on NHL limes and their applications. Now then; I've embarked on attempting to re point a 120 yr old external wall. I seek neither methodology nor lime recipes. Time will tell, if my feeble efforts will fail or not. Assuming I've applied a 'friable' mix; sandy mix , or damn bugger nose what mix, my question Mike is this: are any of these mixes detrimental to a wall that was otherwise 65% devoid of any mortar joints whatsoever? Am I helping or hindering the wall with my DIY attempts? I'm thinking now I should have perhaps left said wall well alone. I won't advise of mix ratio. Too; I'm not seeking 'set in stone' secrets...(pun intended.), from yourself neither. I'm honestly thinking the voids in the wall were probably fairing well enough, given the air blowing through them probably aids in the wall drying out process before I came along and attempted to treat it with lime mortar. Thoughts? Cheers. Les

[@michaeljamesdesign]

House or garden wall?

[@tablettwentytwo1750]

@@michaeljamesdesign External garden wall....

[@michaeljamesdesign]

@@tablettwentytwo1750 It sounds like it may well have been dry built. They often get pointed up but as there's no mortar in the centre and they flex a lot then the mortar tends to fall out. Look to see if there's stone packing in the middle and if so it's dry built so won't ever need pointing.

[@grantduncan7301]

St asteirs on there website ; restoration and conservation. Paragraph 3 states that a high free lime content might not be as suitable as they are supposed to be. They give all the reasons for that. Interesting , contrary to what i was thinking.

[@michaeljamesdesign]

I think you have to look at the original mortar in your property and try and match likewise. It's always the case that a high free lime content pointing mortar was used for older properties. I know what works in most areas of England but one has to allow for pozzolanic addition.

[@quantumofconscience6538]

Well, obviously pour OFF the water at the top of the lime putty bucket before mixing with sand, mix for a long time, and give it a long time to "set up"

[@michaeljamesdesign]

Is that a fact.

[@grantduncan7301]

...and my last coments on the matter , st asteirs paragraph 2 also states important information on free lime content. You also state in this video that there would be no point in using NHL 5 , you would be as well using cement . Compression strength of a cement morter , 28 to 40 ish N/nn.....NHL 5 St Astiers........Under 9 N/nn and many times more permeable .

[@michaeljamesdesign]

I all depends on the NHL5. But that aside, let me ask you this: what's the compressive strength of a St A NHL 5 after 5 years? Does it increase in compressive strength between 5 and 10 years?

[@as3cs3]

I think he's rambling @grant duncan. he hasn't read any of the information on the manufacturer's sites and gives bizarre answers when anyone wants a detailed response.

[@winnieman-fx1hu]

The puddle and cars splashing it up the wall is probably a big issue too

[@michaeljamesdesign]

Au contraire. Old mills were always built beside water so this could be used to drive the water-wheel to grind the grain to flour. The buildings always stayed dry; they had to as wet flour meant starvation. And yet, all people have been wanting to do since the 60s is tank them. Lime mortar is incredibly tough and will outlast cement by hundreds of years. A bit of splashing wont hurt it. It's necessary to wick away the moisture from the stone and keep it dry.

[@winnieman-fx1hu]

@@michaeljamesdesign I completely agree. i did say "too"! if it is constantly being splashed, it wont have the opportunity to ever dry out. another thing to consider is the effect of road salt being splashed on the wall, salt can destroy some stone

[@michaeljamesdesign]

@@winnieman-fx1huIt's not being continually splashed and the base is very dry. The stone at ground level is sound. On these old houses it's often the apex which suffers the most. Thanks for taking the time to comment.

[@lxpollitt]

Thanks for making this video. I learnt a lot from it. Unfortunately I've found it very difficult to compare NHL product since the datasheets vary so much in what information they include. My local builders merchant stock Rugby NHL 3.5 (Cemex) which say all the right things in the marketing material about suitability but I can't the information you mentioned as being important. (Or if it is there, I don't have knowledge recognise it.) I have some repointing to do on a 1930s brick building (mix of red and yellow bricks) which has lime mortar currently and I'm thinking this NHL 3.5 is probably going to be fine for that - but it's just a guess. The local builder who has repointed many houses on the street uses 1:1:6 lime:cement:sand mix, but if I've understood correctly this just acts as a plasteriser and doesn't significantly increase breathability compared to cement mortar (or certainly not as much as NHL would?). I've really struggled to find out more. Do you have any insights? Or can you point me in a direction of resources to learn more without having to spend many days reading books or similar?

[@michaeljamesdesign]

1:1:6 is a standard builder repointing mix. Guaranteed to fail and guaranteed to cause damp and rot stone and brick. There are worse products than Rugby 3.5. It'll roughly 25% free lime so will have some vapour permeability and will always have higher capillarity than cement mortar. However, there're much better high free lime content NHLs being sold be Chalkdown Lime. There you'll get around 40% which means more capillarity. LaFarge Nathural has a free lime rate of 44%. Or you could go for NHL2 which is a bit softer. And read Nigel Copsey's book.

[@shaunpage4498]

@@michaeljamesdesign I'm reading Nigel Copsey's book based on your recommendation to this person above. I'm a restoration carpenter in the USA but not a mason, and am definitely struggling with his book as he makes the assumption that the reader knows pretty well what he's talking about. It seems his target audience old-work masons in the UK who are used to using NHL mortars.

[@michaeljamesdesign]

@@shaunpage4498 The book is derived from an MA which he did at York. It needs to be approached from an understanding of common (earth) mortars inherent in propertied built circa 1700. Most of the heritage which remains in the UK was built in this century. We lost our understanding of working with timber framed houses and plaster because of the second world war. So we're all having to re-learn the crafts. The best thing you can do is back your reading up with some of Nigel's youtube tutorials. You're not along. The scales do eventually fall away and when they do you'll wonder why you didn't get it.

[@richardgrimbleby7853]

You don't actually learn off this guy he just trys to give an air of mystery of secrets only he knows

[@michaeljamesdesign]

Depends on what you want to learn. These videos are based around my need to attract good clients and not good students. They're promotional videos and not teaching aids. Very few people will show you how to do it because their living depends on their knowledge base remaining exclusively there's. Sorry I couldn't help.

[@richardgrimbleby7853]

​@@michaeljamesdesign ah so more of an advert sorry

[@grantduncan7301]

I had mentioned that it in my humble opinion that i thought St Asteirs produce a outstanding product. You replied to say speak to chalk down about St Asteirs . I responded to say it may be worth speaking to masons morter on there thoughts regarding lafarge.

[@michaeljamesdesign]

Sorry mate, I'm still not with you. Are you suggesting I speak to Masons Mortar concerning Lafarge?

[@Southpoint2019]

Quicklime all the way.

[@dangreen9446]

Hello. I just wondered if you suffered from shrinkage and small cracks when using quickline in the Summer months...? Thanks.

[@peterwalton1502]

Why should people find this out for themselves? Isn’t that what your channel should be about helping people making informed decisions?

[@michaeljamesdesign]

Making one's own discoveries is learning. Good teaching isn't about serving information. People feel much better about themselves when they make their own discoveries. I'm happy to aid and facilitate but it's not actually my job to teach. I gave that up years ago.

[@DevAnubis]

It needs to be common knowledge... But I'm not going to tell you... That's not how you get to common knowledge...

[@IannoneBuilding]

I am in the dead middle of the worlds Arse hole for historic masonry restoration, please make an exception on your rule of not revealing the brand's that work. I am 38 years old, passionate about saving historic masonry, even the dwellings owned by individuals who could never afford one of the few national restoration companies we have in the USA. It took me months to find an actual supplier of lime anything. There was no lime putty, no premixed lime plaster bags, no NHL, no quicklime, no limewash, not even any hydrated lime available for sale in my town, county, or even state... which is crazy because I live in NYS. I literally drive 8 plus hours round trip twice a year with a truck and trailer to purchase various lime products, natural aggregates, and natural additives. Shipping cost makes it an impractical solution. What this means is that I only have access to literally three or four brands, two of which were on your do not use list, and two of which are not, the brand I normally use you did not mention, so I am praying I am getting quality product. The mortars and plasters I mix and use are significantly better than portland cement based mortars in every aspect I can think of, but, the one thing I am always fighting is the lack of knowledge and overload of ignorance about historic masonry and the special materials and methods required to properly and safely restore, repair, or preserve it. Meaning I really cant afford to have these code idiots find one reason to throw me off a project and have one of their destructive forces take over... if I see one more beautiful stone, brick, early concrete building fail due to Portland cement or disrepair due to financial lacking on the part of the owner, I may just go back to breaking fingers and collecting loans for a living. Seriously, it saddens me everytime another building is lost... if I provide you the names of the brands available to me. Can you provide me your honest opinion of them, please. I had no teacher, no mentor, no help whatsoever on this journey, just a felony on my record and my only legal passion being masonry, which through shear determination, passion, and hard work (and, a lot of research, and trial and error testing....) I have managed to make a difference and have saved numerous deteriorating, crumbling, or collapsing historic structures all using historical compatible building materials and methods, but, like I said, the powers at be would rather see me fail and their old buildings gone, than for otherwise.... sincerely, a desperate, but determined upcoming, middle aged, historic restoration and preservation mason!

[@michaeljamesdesign]

I feel your pain brother. Please forward brand names and I'll tell you if I've heard of them. I might not though. I am surprised that you can't get any lime hydrate. As I understand it, it's a component of S type mortar so should be readily available. Used fresh then this is fine mixed with 3 or 4 gauges of sand.

[@IannoneBuilding]

@@michaeljamesdesignthank you kindly for your quick and approving reply! Much appreciate your honest and highly expert advice, on anything your willing to pass on to a not so young, but young in the game lad! Apparently I only have two choices now, and neither are the one I have been using, and rather liked the workability of with both natural and very sharp local sand, and well graded, fine quartz plaster sand (as well as, the results have so far been quite amazing as compared to Portland based products, but that's not that difficult to do! lol.... ) which was "Roundtower." The brand my usual supplier now carries is "Secil Tek," which I obviously have not tried, having just found out about the change to this product. The other brand is the ever famous, St. Astier, which I could have sworn you said to avoid in this video, but, in another video, you seemed to be approving of it, for certain applications... but, preferred the cl90. So, while impatiently awaiting your possible reply, this whole availability and newly discovered NHL information making me extremely uneasy, I started sourcing quicklime suppliers, with poor luck, unless willing to pay a large upcharge for shipping. Then, last night, I made a first attempt at making my own, but, due to a misunderstanding with assuming the info I found was in farenheit, like a dumb American would, haha, I failed. Tonight its raining, but tomorrow I will give it a second go, now armed with a newly purchased infrared temperature device and a powerful blower to achieve the heat required... My wife's reaction when I told her about my upcoming experiments was priceless, "very interesting, I am curious to see how it turns out..... just please don't blow up our garage.... we can't afford that right now...." :)

[@michaeljamesdesign]

@@IannoneBuilding Secil are getting in everywhere. Their marketing strategy must be one of a kind. The problem with Secil is it's really cheap shit which has traces of gypsum and amounts of chalk to make up for the lack of available lime. It's also from rock which is high in clay. In direct contrast St Astier is made from siliceous rock and it also which makes for a more attractive finished mortar. St Astier is a quality product and it's a favourite of mine. I try to go for NHL2 when and where I can. Depending on the size of joints you may need some sharp sand. For brickwork I tend to not bother but for stone I always include a gauge. The only problem with NHLs is their ongoing need for hydration and their increase in compressive strength. Because of the availability of quicklime we tend not to use them nowadays but there's always a place for them. Particularly on walls regularly saturated with rainfall, permanently damp areas, cold and wet north facing elevations, working at height etc etc. But any NHL is preferable to Portland Cement. It's all about capillarity and quicklime ranks the highest here. If I were you I'd steam ahead with the St A. If you want quicklime then maybe an agricultral supplier might be an option as it's used as a soil conditioner. The only problem you might have is volume as it's difficult to get it in 25kg bags. However, quicklime as a soil conditioner might be more readily available as it's used extensively by gardeners to bring down acidity levels in soil. Just don't use Dolomitic lime and if using quicklime then don't go any lower than CL70.

[@IannoneBuilding]

@@michaeljamesdesign omg, you are a damn good man for providing me with this rare and important information! I will always take the word of a skilled tradesman with personal experience over suppliers, manufacturers, or, usually, academics (with the exception of A.) My wife, who is a brillant Art Histotian who specializes in the study of Byzantine Enamel and B.) The majority of gentlemen and gentlewomen in Europe with regards to Historic Masonry research, they are top notch in my book.) I really just dont get how people here, in the USA, completely disregard the importance of, and, necessity for, using compatible materials on these amazing old buildings and structures. I mean, I dont get it, but, I do understand it, because the vast majority of Americans possess a general lack of knowledge, care, respect, patience, appreciation, attention to detail, and/or pride in thy self, their workmanship, and one's trade; instead, they possess in abundance the following traits: ignorance, selfishness, greed, laziness, stubborness, and a complete disregard for traditions, history, or anything involving hard physical labor. Not to mention, their ridiculous and negative view towards any/all artisans/craftsmen/artists/skilled tradespersons, and, most notably, towards laborers. People here would rather completely knock down a magnificent historic building or structure that is full of history and was built with skill, pride, and hard work, instead of preserving, restoring, or repairing them; only to erect some modern day monstrosity built with either recycled steel *the reason trucks ten years old are falling to pieces quite literally, whilst pre-1985 trucks are still functional and structurally sound*, or pressure treated genetically modified lumber (33% weaker than the same dimension lumber was 100 years ago), that will sit on an oversized footer, with one foot thick concrete foundation walls *which I will likely be called to repair within 5 to 10 years time of its buidling*, and, then clad it with a plethora of ugly, poorly made, and worthless siding materials such as thin brick veneer, artificial stone veneer, or worse still, fiber cement siding or vinyl siding (which at least the vinyl keeps the walls dry if installed correctly, but talk about ugly....) When today's children finally grow up, they will most likely not know what an actual solid brick, mortar, stucco/plaster, or veneer plaster even is, let alone how to make or use them (it), and, I will be surprised if any will have the desire, and be both able and willing, to become masons. I personally am trying to change that as much as I possibly can with the few resources and time I have available... and, having no one, I myself can learn from in person, unless of course, I had thousands of dollars to take actual classes taught by the few experts who live in America and offer them, at a high cost, to the public. Which I do not, nor is my faith in their expert knowledge and ability. Basically, this novella is my attempt at illustrating to you how important your knowledge is, and how appreciative I am of it and you. You arent just helping one curious mason, but hopefully, this information will be inspiring and educating a new generation of skilled, intelligent/knowledgeable, and proud "heritage" masons. (Here we are called "historic masonry restoration/preservation experts" we have to overcomplicate everything here.) THANK YOU

[@SuperDiagnostic]

Just don't get it.. you are trying to educate yet don't help when it comes to product. Are you running a consultancy perhaps? Clearly your unable to work everywhere so why not help the end user and get your point across so we can all do the right thing and preserve buildings? I'm in Portugal BTW if you fancy a bus-mans-holiday, I'll point you at the building and give you the keys if your interested?

[@michaeljamesdesign]

I used to be a psychology teacher and I never gave my students the answers. Instead they had to use their brains and go do the work themselves rather than just sitting back and passively receiving. There's no merit in that. Teaching is creating a hunger and providing motivation whilst offering up information. But never too much. I've offered up heaps of information in this video and someone has already clarified a good brand in the comments. So wake up. I'm the same with apprentices, they have to learn to become independent of thought and get creative so I give them space to make their mistakes. Teaching and learning is dynamic. I'm doing my bit so do yours.

[@jacobnadin8513]

@@michaeljamesdesign Absolutely agree. So well put. A bunch of dummies working with the right materials won't get the right job done - that's why most people do terrible work nowadays; because they just don't have enough depth of understanding...about anything let alone building. There's my psychology 101 on the building trade; whether you asked for it or not.

[@michaeljamesdesign]

@@jacobnadin8513 Much appreciated Jacob. Always welcome.

[@as3cs3]

@@jacobnadin8513 so they wouldn't get the job done better by following correct guidance?

[@295walk]

@@michaeljamesdesign I was just thinking this as clearly you said 'im not going to tell you' Brilliant as it gets us researching further to hopefully build up a circle of awareness and knowledge

[@as3cs3]

this is possibly the most annoying video I've ever watched: you give a list of mortars not to use yet don't recommend any that you should use. You veer off into a pointless bit about NHL5, when immediately prior, you were on 3.5. I had to rewind to make sure I was understanding it right. The things you said about NHL5 were lifted straight off stuff I've seen before (sea defences etc) but you (angrily) say ppl would be as well using cement instead of NHL5 when other sources suggest the 5 (newtons or whatever) strength of that is way lower than the 46 (?) attributed to cement. You cite certain brands of NHL3.5 as not having much free lime in them etc etc. Where are you getting this information from? Have you done a chemical analysis of the makeup of all the brands you dissed? If all you are saying about the 3.5 from these brands is correct would it not be better using their NHL2. I could go on further but would have to go back and listen to the whole thing again. It sounds like a lot of unscientific rambling to me

[@ianmorgan8624]

all a bit secretive with the lime. sorry but you just annoy me rather than offer some good advice.

[@michaeljamesdesign]

That'll all stop soon. Thing is, when you rely on a trade you can't dish out all the knowledge otherwise you ain't got a job.

[@user-lt3qd9pz6o]

Totally confusing

[@michaeljamesdesign]

Sorry. How can i unconfuse it? How may I help.