Thank you for the video, excellent work. Slightly concerned following textbook advise: Normally limecrete floor screed (sharp sand & nhl5 lime) is mixed dry in a forced action pan mixer. your floor is wet because you had to use a cement mixer. Did the floor crack after water evaporation ? Has it fully cured.
Someone please.. the accent is hard for me to understand. What is the dark aggregate material in the bags. It appears to be very light. Is plain old lime used for the cement? What is the ratio? How much water? Why was the dark granular material put on the bottom? Is this structural or just for sidewalks? In the United States we specify strength by number of sacks of concrete per cubic yard of finished material. 4 sack, 6 sack, etc will give varying strengths. Does the same principal apply with lime.. is there a minimum mix.. is there a maximum desirable mix? What is the light granular material @ 12:13?
The aggregate is LECA (lightweight expanded clay aggregate) foamed glass is also available and has better U valves. Use 10-20mm coated LECA for the loose insulation layer circa 300mm thick, the large pore spaces act as a capillary break negating the need for a DPM in a historic structure. The hessian is acting as a layer separation mechanism, i'd recommend a open plastic geotextile for the base layer as the Hessian would rot in damper areas such as Cornwall. The 100mm thick screeded layer should be 3 parts 0-20mm uncoated LECA and I'd add a couple of handfuls of 30mm fibreglass hair per mix and one part hydraulic lime NHL 5. The resulting leca-crete is strong and breathable - which is the point of the above demo video. If you are not worried about breathability of a building (which you should be in a historic one
The person leading the tutorial says in the video that the hessian is used to prevent the limecrete from draining into the insulating aggregate they laid. He also acknowledges that some people think it's not necessary. I'm just guessing, but perhaps one reason is that if the limecrete slab itself is not touching compacted soil below the insulating gravel, and just floats on top of it (many people use a special kind of glass gravel which is whipped full of air, to make it very insulating), then it's harder for heat to conduct out of the slab. As I understand it, there is also some kind of thin layer of cork that goes between the slab where it meets the walls, also for the purpose of making it harder for heat to leave the slab. Just a guess.
Quite clearly these people don’t really know much at all. Together with the little concern for the students well being all skin should be covered all those people near to the mixer should be wearing goggles. Joke really.
Thank you to the Tutors. Very informative.
What are the proportions for lime, sand and LECA for the limecrete please?
don't you need a reinforcement for the floor slab?
Thanks for posting this interesting video. The lack of dust masks makes me cringe though!
Thank you for the video, excellent work. Slightly concerned following textbook advise: Normally limecrete floor screed (sharp sand & nhl5 lime) is mixed dry in a forced action pan mixer. your floor is wet because you had to use a cement mixer. Did the floor crack after water evaporation ? Has it fully cured.
i know Im kinda randomly asking but does anyone know a good site to stream new series online?
So a pallet Jack to move the form to cement mixer?
Someone please.. the accent is hard for me to understand. What is the dark aggregate material in the bags. It appears to be very light. Is plain old lime used for the cement? What is the ratio? How much water? Why was the dark granular material put on the bottom? Is this structural or just for sidewalks? In the United States we specify strength by number of sacks of concrete per cubic yard of finished material. 4 sack, 6 sack, etc will give varying strengths. Does the same principal apply with lime.. is there a minimum mix.. is there a maximum desirable mix? What is the light granular material @ 12:13?
The aggregate is LECA (lightweight expanded clay aggregate) foamed glass is also available and has better U valves. Use 10-20mm coated LECA for the loose insulation layer circa 300mm thick, the large pore spaces act as a capillary break negating the need for a DPM in a historic structure. The hessian is acting as a layer separation mechanism, i'd recommend a open plastic geotextile for the base layer as the Hessian would rot in damper areas such as Cornwall. The 100mm thick screeded layer should be 3 parts 0-20mm uncoated LECA and I'd add a couple of handfuls of 30mm fibreglass hair per mix and one part hydraulic lime NHL 5. The resulting leca-crete is strong and breathable - which is the point of the above demo video. If you are not worried about breathability of a building (which you should be in a historic one
Thank you!
I think it is charcoal ..it's like volcanic rocks
@@rupertridout-jamieson85 what is opc you refer to
@@colmgray OPC=Ordinary Portland Cement
Optiroc fill perhaps
Headphone user warning in 3:00
I Can't understand why hessian layers were used?
The person leading the tutorial says in the video that the hessian is used to prevent the limecrete from draining into the insulating aggregate they laid. He also acknowledges that some people think it's not necessary. I'm just guessing, but perhaps one reason is that if the limecrete slab itself is not touching compacted soil below the insulating gravel, and just floats on top of it (many people use a special kind of glass gravel which is whipped full of air, to make it very insulating), then it's harder for heat to conduct out of the slab. As I understand it, there is also some kind of thin layer of cork that goes between the slab where it meets the walls, also for the purpose of making it harder for heat to leave the slab. Just a guess.
Never trust a guy who puts his collar up in 2011.
Quite clearly these people don’t really know much at all. Together with the little concern for the students well being all skin should be covered all those people near to the mixer should be wearing goggles. Joke really.
That group is too big to teach.