Experimenting with HEMP Lime Plaster

We're planning to use hemp lime plaster to add some additional insulation to our walls but there's a problem.
We don't know if it's possible to hot mix lime (quicklime) and hemp and we don't know the most suitable ratio of hemp to lime when working with quicklime.
So it's time for an experiment. We have no idea if this is going to work but we'll do a few test mixes to see what seems to be the best. And then we'll test our almost non-existent plastering skills. What could possibly go wrong?
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www.makedogrow.com
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Here's some links to other videos relating to hemp plastering
Hemp plastering with a trowel: • 21. Plastering with Hemp
Lime hemp plaster with hands: • Insulating a Solid wal...

[@reannejarvis9464]

This is exciting …getting plastered with Kylie and Guy. Great Saturday night. Rock on🇦🇺🎸⚡️🤘🏿🤘🏼💋❤️ a silicone oven mitt could be useful to smooth it in

[@carlroge]

Such a good solution to the cement problem, and you'd never get a first coat of render on that thick. Brilliant work

[@bobyonker8642]

Oh my goodness. My wife gasped when you made the statement "the first coat". It is very interesting to watch and see what you discover and accomplish. You two are very industrious and fun to watch. Thanks for sharing your experiences.

[@sandyziegler592]

Thanks

[@steveevans1247]

I haven't seen any videos explaining all the different types of lime. I would find that interesting. great work.

[@MAKEDOGROW]

We’ve got some explanations in a few different videos, but perhaps in the future we’ll do a consolidated one. Try these in the meantime: kzbin.info/www/bejne/hZjdaZd6oqxgn7s kzbin.info/www/bejne/e6bTc3qcf8ekqtU kzbin.info/www/bejne/i32Wo3eaedmee9U

[@suesparks4301]

I use that exact hemp in the UK to put in my raised beds as an organic, moisture retaining, bug repelling and soil nourishing material and is available on Amazon... love the idea of using this mix 👍 Great work 👏👏

[@MAKEDOGROW]

Hadn’t thought of using it in the raised beds, but what a great idea. Definitely going to mix some into the next couple we build, and use as a mulch where we need it 😀

[@nancibishof6462]

Portugal from Scratch is also using lime hemp to build/plaster. She is first slaking the lime then adding in the hemp after the lime is slaked.

[@bofostudio]

I'm really looking forward to the update after it's properly set and you've added the topcoat. Fascinating stuff, thank you!

[@MAKEDOGROW]

That might be quite some time from now, it’s probably going to take us a couple of months just to get the scratch coat on 😂

[@luminyam6145]

I love your courage to just try new things. You guys are awesome 💖

[@tracybrown6207]

interesting. Could you do a thick hemp layer for the insulation value and then just a lime top layer to make it smooth. Problem with 'bumpy' walls is they get dusty and you either have to sweep or vacuum them regularly. Ive also seen people use a sponge to get a smooth finish on lime after leaving the plaster for a while, that might be an option to get it smoother. Good luck

[@florentinalily]

if you wet the trowel to trowel it up after you have hurled it onto the wall it's easier. (we threw it onto the wall in blobs then trowelled up with the wet trowel) The consistency looks fine - and then you can polish it up with a watered trowel without overwetting. The final coat can be just a fine lime plaster. I find using my hands is just too slow and I can't get it off my gloves.. and also eats through gloves faster than I can get them😁 We also put on three coats - two of hemp lime and one final finishing plaster coat

[@MAKEDOGROW]

Yeah, we’ve been thinking a more hurling type approach might work better, especially on the big walls. Did you add any sand to your mix? We’re thinking to experiment with that for our float coat

[@florentinalily]

@@MAKEDOGROW No we didn't add sand to the hemp mix base but for the float coat we did go back to using 1:3 slaked lime and fine sand with hemp. Then 1:1 slaked lime and fine sand for the finishing coat.

[@MAKEDOGROW]

@@florentinalily that’s pretty much what we’re thinking of doing - a really fibrous (and thus max insulating properties) for the base cost, then some sand in the float coat to make it more smooth. Depending what the float coat looks like we might only do a top cost in some places … in effect so we get different finishes in different rooms

[@florentinalily]

@@MAKEDOGROW it's looking great! I use Distemper on the walls by Little Greene.

[@stevewoodw]

It might be worth getting the temperature within the rooms (compared to outside) that you're putting the lime-hemp mix on the walls, if you haven't already, so you can say if there's a big temperature difference (cooler inside in summer/warmer inside in winter) when you've hempcreted the walls. With hemp insulation, it's thick and there will be more data available on it and how well it insulates - with this mix it will be similar to when walls are made from hempcrete. I haven't seen this used elsewhere with some data on how effective it is. Potentially there is something quite interesting you could do in terms of gathering data but with open doorways you're not likely to be able to do more than try to generate some general info - but this isn't that readily available. Good video..

[@sueg2658]

It reminds me of cream cheese frosting with toasted coconut. Looks very promising!

[@laurareiner]

I was thinking of crabmeat-cream cheese dip. Yum.

[@leestimis9264]

Hemp use is the bomb diggity. Love learning along with you 2

[@sjblack9135]

I’m really glad Kylie is the one who said it looks like tuna mayonnaise, because that’s exactly what I was thinking! I think you guys are doing such a clever job of it, and once it’s on the wall it looks great!

[@monalingan9523]

This is a very interesting plaster combination. I’ve never heard of using hemp in plaster, but I can see how advantageous it is. Kylie was really filling up indentations quickly.

[@neagacosmin8265]

Hemp is a wonder-plant! It's great that you are experimenting with it! There are thousands of products that can be made out of it, from bread flour to furniture grade particle boards... Maybe the smell reminded you of beer brewing because hemp is in the same family with hop... If you want to add a thermal insulation to the house, there are some 40x80 cm and 10-20 cm thick (or something similar) indoor hemp thermal insulation rigid blocks instead of rockwool. Being rigid, i think it can be used also under the floor boards. Good luck!

[@jackpatteeuw9244]

Hemp and marijuana are NOT the same plant. Close cousins, but not the same. Hemp has almost ZERO THC.

[@neagacosmin8265]

@@jackpatteeuw9244 Yes, i know, hemp has under 0,5% THC, i was talking about industrial hemp in my comment, not its medical/recreational cousin.

[@jackpatteeuw9244]

@@neagacosmin8265 Just informing the rest of the viewing public. I know industrial hemp can be used for a variety of purposes, I just don't know what they are.

[@dianeleirer9878]

@@jackpatteeuw9244 Hemp rope production was nudged out by nylon. And with regards to the hemp/ marijuana confusion, marijuana growers actually don’t want hemp plants growing in proximity to their crops-if I remember correctly, the cross-pollination that can occur reduces the marijuana potency. The documentary “Hempsters” was fascinating. I’m glad to see a renewal of hemp growing.

[@jimurrata6785]

4:15 on, Kylie trying to get around calling hemp a weed just cracks me up! 😅 It's always great to watch you two experiment and build new ski!!s.

[@vickihoneycutt456]

Absolutely excellent work 👏

[@j963s]

Just thinking you may want to pre-soak the hemp fibers before you mix it in, this could eliviate the issue of the hemp pulling all the moisture while mixing up a batch.

[@ladyrickysummers777]

Hi you guy's Nick from "Project Portugal" is a true handyman and he always help everyone around the area. He have a great nolige of building and all different things. He is our super hero well loved by the of grid farmer's. 🐓🍷🌶

[@sadjaxx]

It is so exciting seeing that entire bit of wall covered, in the name of experimentation!

[@MAKEDOGROW]

Looks even better now that it’s dried 😀 Eagerly waiting for our pallets of hemp to arrive so we can crack on with the bigger walls

[@jeniceowen5184]

Very interesting. You two are so hard working!

[@lynh8378]

Ya'll come up with some really neat ideas. Love the sound of the bubbly lime lol.

[@SwimCoach8]

Have you considered pre wetting/soaking the hemp? The hemp wouldn't be fight with the slaking process to absorb water. Just a though. The whole idea of including hemp it really interesting. Can't wait to see the final out come. Thanks for all your time, good luck!

[@CarolSteele]

Yes, I was going to suggest that maybe you hadn't calculated in that the hemp would adsorb some of the water that you added - which would account for the density of the original mix.

[@suesparks4301]

I really appreciate the time you take to make your videos and inclusion of ratios as someone who may want to follow your research with this mix or any materials, onto an old stone wall... Good work and good luck 👏👏👍

[@Hagar2670]

I was going to suggest that they wet the hemp and let it absorb the water it needs/wants While the Lime is slacking, then mix the things together. So the mix would be Lime Putty, sand and hemp water to get the consistency you want.

[@MAKEDOGROW]

If you were to pre soak the hemp it would then take a lot longer for the walls to dry. There’s a really fine balance between hydrating the lime correctly and not over soaking the hemp. We’re going to try a couple of different mix orders once our hemp arrives, we have a few ideas that should make things a little better

[@heathermorgan2265]

Whoo way to go guys that is looking really good brilliant job 👏

[@moiragoldsmith7052]

That looks lovely to work with! 😃🥰. Hope it dries beautifully.🤞🙏

[@WPGinfo]

Great fun! Can't wait to see the end result

[@tracy2092]

I love how the hemp plaster looks 👌👌

[@onefatmanbetterthantwofatl2886]

I am really enjoying your Videoes and I am sure you will work out the right ratio for the hemp lime keep up the good work

[@carolerodeghiero8157]

Love watching the process of what ratio is best

[@dawndyreed8031]

Love how it looks. Keep on......love your videos.

[@gaynor3976]

What do I know about plastering but I think that wall you've done looks really good and has a interesting surface. Well done both of you, can't wait to see the other walls done the same xx

[@marcellasimerly8233]

Wow. Hemp lime breathing walls. Wow. Good job.

[@Allison-405]

Aussie tradition to just give it a crack! Good experiments you two!

[@jenniferbaker19]

Great work

[@lisascenic]

Very impressive! Your sampling process is commendable. I use recycled paper pulp as an additive to some of the textures I make to cover theatrical scenery. We’ve found that ore-soaking it got about an hour makes a huge difference in the overall consistency of our mix. A decorative painter friend uses a cheap flip-flop when she’s plastering any walls that aren’t flat. She swears by them, because they conform to the surface of the wall. I also really like swimming pool trowels, which are more oval than rectangular. I find this keeps me from having to spend a lot of time battling tool marks.

[@ScaseFacetime]

🤯 I hope it all turns out well! I have seen other channels use a ready made hemp block solution with loose hemp behind. Good luck, but then you guys do so much research I think you won’t need it 👍🏻

[@norma2310]

Hemp is the future, hemp will replace plastic and it’s fast growing, great for clothing, win win!

[@bcarithers22]

I really enjoy your process of experimenting. I used fiberglass strands mixed into clay for added strength in making sculpture. The hemp may need more water in the mix because of being an absorbent material. I hope it drys well and sticks well as it drys. Love your attitudes and your channel!

[@footplate0]

This looks like quite a bit of fun and hard work all at the same time. I think a lot of lime plaster walls are made up of 3 layers. Each layer taking over a week to dry, but you more than likely all ready know that. Maybe pre-soaking the hemp might improve the handling of the finished plaster. I honestly don't know, but it would be interesting to see the results of this and other experiments that you could dream up. Well done in trying this, hemp was used a heck of a lot in the 1900's but has seemed to be out of favour these days. I am in favour of the ball, splat and mush approach to apply the plaster. It just seems a so satisfying approach to doing things. Thanks very much for posting this very enjoyable video

[@dianeleirer9878]

Make. Do. Grow……Ball. Splat. Mush.😆

[@rubiracing6637]

nice work is gonna look great.

[@Ida-fz3ir]

I took for my walls (nature granit rocks) -> Weber's Dress... and I'm very satisfied!

[@apmgold]

Great insight into the process of discovering the trials and tribulations of developing a new set of skills. As a humble suggestion, would dampening the wall help reduce the drying out of the plaster mix. Currently it is possible that the water is being drawn into the wall and this may be giving you issues. Good luck, I'm sure you will get there in the end. 👍

[@MAKEDOGROW]

The wall had been sprayed down, just not on video 😀 Needs to be sprayed down only a little however, and in some instances not at all (unlike when doing pure lime plastering)

[@apmgold]

@@MAKEDOGROW OK. Just trying to help. Keep at it, you will nail it in the very near future, I'm sure👍

[@MAKEDOGROW]

@@apmgold we still have a couple more experiments to do once the big batch of hemp arrives … I’m sure we’ll eventually get to something that we both like 😃

[@SuperAbcdabcdabcdabc]

You two are hilarious. I could hear the moisture as you were slapping it on and I could see the fibres. The high lime mix looked like a child’s putty craft type mix and the high hemp looked like a scone mix.

[@machellep1]

Recommendations I’m finding are 2 parts lime binder to 1 part hemp by weight . Add water a little at a time till you get the consistency you want. Important not to over due water. I’m sure you will find your perfect mix.

[@MAKEDOGROW]

Unfortunately that’s not a hot mix recipe. When hot mixing all the water has to be added to the lime at the same time else the lime won’t slake properly. Sounds more like a nhl + hemp recipe 😀

[@bccochrane1]

Good work you two, it’s great seeing how thorough you are in trying new things. I’ve worked with lime for 10 years but never used hemp. You could slake some hot lime to a putty and then mix that 50/50 with a fine sand to use as the top coat. Best of luck with it, really enjoy watching your vids 👍🏻

[@MAKEDOGROW]

We have a couple of barrels of slaked lime waiting in the wings … we might experiment with it too just for fun 😀

[@tobiaswinkler6971]

O man, this video shows why builders won’t do anything with this guys. They must have it very hard

[@andreacrashe9894]

*Kylie and Guy getting totally 'plastered' from top to bottom... I am thinking that Kylie's way of doing it all by hand, was going on faster... But maybe time each other as a test, to see how much wall gets covered in say 1 hour. A little competition for you both.*

[@davidfellowes1628]

Brilliant thanks

[@jimmyjohnstone5878]

I like the practical experimental process which you used on this. It is not a disaster if it doesn't dry as it should once on the wall as you can always scrape it out and start again.

[@MAKEDOGROW]

The good news is it’s dried well, and we think it looks awesome 😃

[@jimmyjohnstone5878]

@@MAKEDOGROW That's great. Have some more wine to celebrate !

[@mariushegli]

I have nothing to say really, but I appreciate your content, and wish to help with the yt-algorithms.

[@lorimontcalm9086]

Looks like working with cobb. You guys, hot sticky balls!!! Too funny you are! Hugs from 🇨🇦

[@DommaPasce]

certainly a vegetable fiber absorbs much more water in a mixture than other types of additions but it will be the cause of the spectacular insulation capacity it will have once dried. 💪

[@rosannehart7325]

Hi to you both. Check out De Hoeve. Old Belgium restoration. They used hemp as an insulation in brick form. They also used hemp behind the block walls as a second form of insulation. Good luck with this project. Looks like you are going to be at it for a while. Love your vlogs.

[@markhellemans3440]

They also do interesting things indeed

[@terrytongacan6042]

I was thinking of those couple too. They seem to be doing okay insulating with hemp. I hope Guy & Kaylie will check them out.

[@rosannehart7325]

Isn’t amazing that even if we aren’t the ones doing renovations, by watching those who do, we can pass on information

[@monicacruz4407]

Kylie, washing up gloves for cob or hempcrete, zero moisture coming through to corrode your skin, but yes, gets a bit sweaty. From what I have seen the lime mix is always applied in thinnish layers, very labour intensive, that’s why heritage building is so expensive. I’ve also often seen the first layer applied like a slurry and flicked on. Love your lime alchemy and the process of finding what works for you. Good luck 👍

[@joy959]

The de Hoeve old Belgian farm channel used hemp bricks and loose hemp behind to insulate their farm. It seemed quite a good idea.

[@sadjaxx]

Seemed to reduce the room size A fair bit tho. This method doesn't seem to to that although they may not need quite so much insulation in Portugal.

[@flowersflowers473]

I think putting at least the first layer on by hand is correct - when they used to insulate houses with cowdung/straw/water in the old days (also a very fibrous and insulatin mix), it was put on by hand.

[@glenyscallaghan1195]

Bye, happy plastering xx❤❤

[@vickiel1284]

Good luck working with your hemp and lime mixture. I found out I was allergic to hemp when working on a macrame project. I hope you don't develop the same allergy.

[@cheryljohnston9723]

Love how you guys aren't afraid to experiment. Also, thank you for making me laugh - you guys are awesome!

[@nena4215]

I’ve never seen anything like that and it is very interesting stuff. I don’t believe you will have many problems with that, the one plastered wall looked quite good.

[@paulan5989]

“You can have a lot of fun with chicken beddings and reactive powders” you are my SML!

[@PauloRSilva-mu3tk]

No shame, but why cover that beautiful stone wall that gives the place such a nice character. I love the channel!! 👊🏼

[@MAKEDOGROW]

Don’t worry, we’ll be exposing some of the stone walls, just not all

[@kelvynnash4333]

Hi Guys, Love your videos . I've watched a guy here in the UK. Called Kris Harbour who used lime plaster to do his walls in his buildings. He might be able to give you some more advice. Best of luck with this.

[@ReformationsGlassArt]

just finished a big job using this - i made a brick kinda shape at the bottom of the wall with hemp, using hands with marigolds ,then made another 'brck'next to it, and so on,then from those bottom rows of bricks i went about ameter along the wall...then added t the top of those bricks, until i was at the ceiling. a circular rubbing motion works best

[@ReformationsGlassArt]

the hemp was about 3 inches thick off the wall

[@hemlock40]

I wonder if pre-wetting the hemp fibers would be helpful in having the mix be more workable, and perhaps dry a bit more gradually. That might help with crack prevention as well as just being easier to mix with the lime and get on the wall into the nooks. Very interesting experiment.

[@Mrs-Emcee]

Very interesting again! They also use hemp for chicken bedding, the deep layering, and because it absorbs so well, you can leave it for up to two years! Some do it even longer. Probably you need much more water in this way of using the hemp… But hey.. I’m not an expert in chickens and plastering either😅

[@offgridwanabe]

I would like the idea more if it could be sprayed on in layers. I see others have similar projects using straw.

[@layna8924]

HELLO KYLIE & GUY...THAT WALL LOOKS SMASHING, ALBEIT WITH A WHOLE LOT OF FIDGETING, ETC. TO GET IT GOING...I DO HOPE YOU WILL LEAVE SOME OF THAT BEAUTIFUL OLD ROCK SHOWING IN THESE ROOMS...IT'S ALL VERY ENTHRALLING & I COULD SIT HERE FOR HOURS WATCHING ALL THIS, BUT, IT WOULD MAKE FOR AN INCREDIBLY EXHAUSTING EFFORT ON YOUR PART...STILL, I DO LOVE THE LONG VIDEOS...ALL THE BEST...🙏🏻;)

[@InonoYazy]

Hemp was traditionally used for walls in Ukraine before the industrial era. Now some designers built some energy-efficient houses with this eco-material to try out. I really see the facture of dry grass i see on the wall you do ( 15:54 ) . WAITING TO SEE HOW IT LOOKS ALL DRIEd.

[@gavin6538]

Soaking the hemp first and then flicking the mix at the wall could be time saving as once the wall is covered you would just need to float it level. When you see a professional pointing a wall they seem to be able to flick it on and it seems to suction and hold that pointing with a trowel doesn’t. Would make a good video and for the two of you no end of wrist action innuendo😉

[@shonalogan1581]

Woodchip wallpaper comes to mind. X

[@rt3box6tx74]

OMG, dying to get my hands in this. It's a cross between finger-painting and sculpting. Hope it dries well.

[@maickelwand9100]

We use linen fibers with CL90 and some fine sand for the finishing layer. The linen strands are somewhat finer I guess.

[@1CelloOne]

hi from Florida! that would be me lol but I love watching your videos -

[@samuelgeiger9691]

Non native english speaker here so I don't know if I use the right wording. You can mix the quicklime and water way in advance and let it sit in e.g. a barrel. The lime should get better over time. In German it is called "Sumpfkalk" swamp-lime or "Grubenkalk" pit-lime. 25 year old pit-lime is also called church-lime because it was used to decorate the inside of churches. You should be able to buy big garden water barrels, put your quicklime and water in an have hydrated lime ready whenever you need it.

[@MAKEDOGROW]

We actually already have 2 barrels of slaked lime, sitting for over a year. We’ll use that when we get to painting but for this type of plaster work we need a lot more than we could produce via this method

[@alwayslearning7672]

It's called Putty in English.

[@lpkay]

The example video using trowel, the hemp fibres were very wet and mixed, mixed, mixed until aerated. Just an observation. You'll figure it out, best of luck!

[@carolbulmer8253]

Good morning, Kylie and Guy. It’s always interesting watching you experimenting. It’s great that you’re using hemp. The resulting texture reminds me a bit of grass wallpaper.

[@dotcorke]

Been watching with interest your channel. Though today been watching something more historical. And picked up a small snippet about Lime Plaster, and thought you may be interested. It was on the site Inside The Fight To Save Henry VIII's Medieval Hunting Lodge | Historic Britain | Absolute History at the time of 16:57. Just a very short snippet, of the Lime plaster they are using to fix a Medieval Building.

[@carlosbotelho1425]

A pouco referi aparas de madeira ,más também se usava palha misturada

[@dropshot1967]

The most used aplication of hemp by far is as a resource for the production of linen the varieties that are used for that are not used for smoking (no active ingredients aka thc)

[@Brigidz]

Quicklime is calcium oxide with the chemical formula CaO. Hydrated lime, which is quicklime with added water, is calcium hydroxide with the chemical formula Ca(OH)2. Chemistry is awesome.

[@notyouraveragegringos]

After the initial mix it looks like oatmeal! We would love to experiment with hempcrete for its insulation and fire resistant properties. Yes we went the cement route. Cement is used successfully in the Caribbean, South America and Central America so it should work fine here. I would think the rainy season in Belize is comparable to the winters here, albeit a lot warmer. 🤔 Guess time will tell.

[@helenavanmaanen6733]

You say cement is used succesfully in South America. My experience of having lived there for 12 years and having seen the difference between adobe/tapial building and cement is that houses built from earth are much warmer and earthquake resistant (as long as they are built with smaller boxes which are being overlapped from one layer over the other, much like bricks in a wall are overlapping, and also interlocking at the corners using an L-shaped box) than cement based houses. The hotel&restaurant I built 25 years ago is still standing and surviving earthquakes, absorbing the heat of the day in the walls and passing it on to the interior during the night thus keeping the temperature comfortable most of the year. (During the rainy season the nights could get chilly, I must be honest. ) My former neighbor built herself a cement bloque house (Ecuador has been heavily influenced in the past 30-odd years by american style box-shaped arquitecture) and at 55 years of age is aching all over her body and unable to work , most likely because of the cold floors and walls. In addition to that, in heavy earthquakes the rigidity of the steel rods will cause the cement blocks will break, whereas adobe/tapial walls have no reinforcement and will move (with the earths movement so to speak but not break nor tumble. Great video Kylie and Guy, learned a lot again.

[@notyouraveragegringos]

@@helenavanmaanen6733 yes the cement vs. natural materials debate could go on forever. Both have their benefits. Adobe buildings are particularly beautiful but we are on a tight time-frame and cement and blocks just goes faster. I survived hurricane Irma 🌀 in Sint Maarten in a cement building sustaining minimal damage. My husband built a house in Ecuador and the builders were Cuban, so it’s a cement house in the Cuban style. So far our house in Portugal is cooler in summer than the original build and we are happy with our renovations to date. We love watching this channel for their creativity and informative approach. They are absolutely amazing!

[@carolined3058]

You are like builders alchimists .

[@royking7298]

Looks like using the hemp, makes the lime plaster a lot more like cobb, and less like regular lime plaster. Therefore using the hands rather than a trowel works best.

[@FranciscoOliveiraDias]

Gosto muito dos vossos vídeos e da forma creativa como abordam as divessas tarefas que têm pela frente. Como estão em Portugal talvez fosse uma boa ideia experimentarem em vez de hemp porque não granulado de cortiça?

[@MAKEDOGROW]

O cânhamo também é cultivado em Portugal ... mas infelizmente os fornecedores que encontrei são demasiado caros em comparação com os outros fornecedores franceses/espanholes. O cânhamo é também melhor do que a cortiça do ponto de vista ambiental. Procurei cânhamo granulado, mas não encontrei ninguém disposto a entregar-nos por um preço razoável.

[@jorgeleite_vvvv]

👌

[@LumunGames]

Have you seen the videos from de hoeve? A couple in Belgium are restoring an old farmhouse and have used solid hemp blocks as insulation. They have some very interesting videos about it that you may find interesting.

[@baggedr32mk5]

Everytime Guy does a piece to camera i can’t but help think he’s the double of Johnny Bravo 🤣

[@richardforster9816]

Hi. Have you tried loo,I gather the old lime plaster. Put it in water and look at what the fibre is. Here in UK horse hair, straw were the go to fibre. Oh! Nearly forgot horse muck, urine were also added. It also appears that the proportions were inthe the hands ,experience of the mixer. The layer you are on now hand fill first then trowel finish leaving a rough finish. Top coat use a lot less hemp or horse hair or even none use slightly more water to make it feel like a gypsum plaster. Hope this helps if not please feel that you can ignore the words of an old man. :-))

[@sandrarooke9921]

Watch de heove farmhouse renovation, they have just insulated with hemp, might be helpful xx

[@jodylynncr]

Your work ethic is superb. I know you have good masks on while mixing but you should be worried about so much fumes inside the enclosed area. Please mix and let the lime cook outdoors. The fumes will be on your skin, eyes, hair and soak into your body. Your skin is the biggest organ the body has. Please be careful.

[@IlkkaVuoristo]

As a material that looks more like cobb or daub than plaster, so the hands-on technique will probably work better. Maybe trowel on just the last coat.

[@flibbertygibbette]

The downside of hemp is that it requires a lot of water to grow. This is not terrible if it's grown in a place with a lot of natural rainfall where it doesn't need irrigation, but if it has to be irrigated, it uses a lot more water than people think and is considered a water-intensive plant. It's also frequently grown with the use of a lot of pesticides, as it's susceptible to a lot of pests and diseases. So it's not quite the wonder plant that a lot of folks think it is, but like flax it can be very useful and versatile. Flax is another extremely sustainable plant and flax can be used like hemp in flaxcrete (like hempcrete), which is strong and has a lot of water and fire resistance.

[@rynait]

i would have gone with much more wetter mix and throw it on walls. then spread -smooth out with finishing trowel. Since you are using hot lime, pre wet your wall before you stick mix on it. I also wonder if lime-wash coat wall then hemp lime layer (then lime plaster layer) on the wall helps?

[@Chateau-Whetstone]

For the technique and background of mixing and working hot lime mortars, it’s worth watching the Nigel Copsey Demo video/s. The mix needs to slake at at least 100 degrees C and you need to be careful not to drown the mix with too much water nor burn it with too little… and probably not a good idea to mix in plastic buckets as the temperature can reach several hundred degrees C if you get the ratios or process wrong!

[@MAKEDOGROW]

We have the book and have been hot mixing for a long time now, it’s just the hemp part that is new. Almost no info out there on how to hot mix with hemp

[@Chateau-Whetstone]

@@MAKEDOGROW Yes... I get where you're coming from. I've been hunting the same info and as you say, it's just not out there. What has helped enormously is the >3hour Nigel Copsey video I mentioned... It's a very different kind of help than his book. Very practical and helps you understand the design parameters and qualities of the various mixes and so can tweak the ratios accordingly. Also, I've been in contact with the people who wrote the Hempcrete book. They recommend equal volumes of hemp shiv to lime binder (for walls and roof). The binders they offer are fast setting but they don't really give much info on the ingredients. They have rapid set qualities, so I suspect some NHL, but I can't be certain...maybe pozzolans?!? The problem Hempcrete UK outline is that with a slow set, the hempcrete can rot before it dries. Like you, I want to use the hot lime mix (using Calbux 90 powder here), so I'm experimenting with ratios, and building up the layers. I'll let you know if I whip up a good mix!

[@MAKEDOGROW]

@@Chateau-Whetstone pretty much everything I’ve read that says ‘fast setting’ has some NHL in it, some though only have 10% which isn’t too bad. But there’s pretty much none of that available here. The hemp provider we found has their own mix but it was 55% nhl which I don’t want. The 1-1 lime-hemp ratio is almost always either hydrated, putty or nhl …. Which equates to 1-2 with our quicklime. … it’s also most often the limecrete mix rather than plaster. For standalone limecrete we’ll use nhl but we don’t want to use that on our stone walls We do have some slaked lime so we’re going to experiment with that too. Will check out Nigel’s video, good to know it’s different to the book 😃

[@andrewmullen4003]

I was going to suggest exactly what you concluded Guy, the lime rich hemp is more a finishing mix, good job. I am not say anything about Kylie and her playing with sweaty balls.

[@midlifecrisistheportugalye6682]

An uncanny resemblance to tuna mayo

[@daddylaugh1983]

I wonder if you do your initial layer of the more fibrous mixture and then use the less fibrous mixture as a finish coat so you have a nice smooth layer

[@MAKEDOGROW]

That’s pretty much the plan, though we do want to experiment with adding some sand into the mix for workability (once the proper hemp arrives)

[@daddylaugh1983]

The sand should be a great addition. I did research on new concrete mixtures in college for my engineering degree. So this video was super interesting. If there is anything I can do to help let me know

[@inelouw]

I'm thinking of doing this with a finer fiber, maybe flax shives. I have the feeling that the plaster would be easier to spread out if the fibers weren't as chunky.

[@MAKEDOGROW]

I asked our supplier about a finer material and he said that the thermal properties are greatly reduced, to the point that most people have stopped using the finer versions. We’re also going to try a 1 sand / 1 hemp / 1 lime mix, apparently it’s more like a traditional plaster consistency. Of course it’s then heavier and reduced thermal properties… but might be a c good option for the float coat

[@inelouw]

@@MAKEDOGROW That's good to know! Thanks!