We are going to plaster our internal walls with lime hemp plaster to try and insulate it but finding the cost is expensive. We are wondering about making it ourseves ie buying the hemp and lime separately but although researching are finding it hard to find out whether you need to use hydraulic or non hydraulic lime and the ratio of the mix.Any ideas anyone please.
- Thread starter Bevmarley
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Flyfisher
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I don't know what you mean by expensive but you may be interested in this 'insulating plaster' product.
http://www.anglialime.com/products/dry-ready-mix-mortars-renders-plasters/thermalime-insulating-lime-plaster
Just pointing out this as a possibility - I've not used it myself.
http://www.anglialime.com/products/dry-ready-mix-mortars-renders-plasters/thermalime-insulating-lime-plaster
Just pointing out this as a possibility - I've not used it myself.
That Thermalime linked to above is a very good product, and will do your job nicely. However, don't have unrealistic expectations as to the thermal performance of any so-called insulating plasters. Their performance is marginal at best, and given the thickness at which they are applied will make very little if any difference to the thermal behaviour of the house. Thermalime, for instance, has about the same insulating qualities as a similar thickness of plywood. Even the best performing insulants currently available would have little impact if fitted in thicknesses typical of plaster (6 to say 20/ 25 mm), and these plasters are no-where near as effective as the best performing modern insulation products.
Bevmarley said:
Places where we've just limewashed the stone are noticeably colder to the touch than where we plastered. It isn't going to save hundreds on your energy bills but it will make the room feel ambit more comfortable.
Plus if as in my case you haven't finished repointing the outside yet, and there are draughts coming through, plaster should at least seal those from the inside until you can get out there in the spring.
88v8
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As has been said, there will not be an economic payback.
However it will make the room a little more comfortable.
More to the point, it will make a significant difference to appearance. If smooth plastered it may look rather.... modern. If you get it bagged so it follows the undulation of the stone, that gives a more rustic appearance. Not all plasterers can do bagging.
As a footnote, I believe that hemp plaster is not used for top coat, the surface being somewhat rough. Rather as an undercoat followed by a conventional lime skim.
Ivor
However it will make the room a little more comfortable.
More to the point, it will make a significant difference to appearance. If smooth plastered it may look rather.... modern. If you get it bagged so it follows the undulation of the stone, that gives a more rustic appearance. Not all plasterers can do bagging.
As a footnote, I believe that hemp plaster is not used for top coat, the surface being somewhat rough. Rather as an undercoat followed by a conventional lime skim.
Ivor
Would something like the Pavatex* wood fibre boards be an option for insulating your walls ?
I've not done any thermal calculations on the stuff, but I'm sure it would be more effective than hemp plaster on its own.
*) https://www.mikewye.co.uk/product-category/natural-insulation/pavatex-wood-fibre-insulation-systems/wood-fibre-insulation-boards-internal-applications/
I've not done any thermal calculations on the stuff, but I'm sure it would be more effective than hemp plaster on its own.
*) https://www.mikewye.co.uk/product-category/natural-insulation/pavatex-wood-fibre-insulation-systems/wood-fibre-insulation-boards-internal-applications/
skier-hughes
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We had hemp lime plaster undercoats in our kitchen and bedroom.
We had normal lime plaster in our bathroom.
I cannot tell the difference between the two in thermal performance.
I would suspect that plastering would help with making the room more comfortable, but I doubt you would ever recoup the money spent, well not in a short period in fuel bills.
We had normal lime plaster in our bathroom.
I cannot tell the difference between the two in thermal performance.
I would suspect that plastering would help with making the room more comfortable, but I doubt you would ever recoup the money spent, well not in a short period in fuel bills.
88v8
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If you have condensation on that wall, the plastering will stop it. In terms of keeping warm, I doubt you will notice the difference.
Ivor
Ivor
If the lime hemp has a slightly warmer surface curing the condensation then the room should heat up a lot faster becuse you won't need the latent heat to evapourate the water. The insulation value isn't great if you're after a constant temperature 24/7 but if you heat periodically (evenings/mornings) then the improved warm-up time will be something you'll appreciate - I believe.
For the record I've just filled a hole in our bedroom wall with lime-fennel plaster - I moved a light fitting and found there was just bare lath underneath with gaps through to the timber cladding that makes up the outer wall and only had finish plaster or coarse stuff available, nothing haired or hemp - so found the closest fibrous plant in the garden and chopped some of that...
For the record I've just filled a hole in our bedroom wall with lime-fennel plaster - I moved a light fitting and found there was just bare lath underneath with gaps through to the timber cladding that makes up the outer wall and only had finish plaster or coarse stuff available, nothing haired or hemp - so found the closest fibrous plant in the garden and chopped some of that...
