Insulation

As insulation should be the first step to reduce bills and make the living space more comfortable an new product popped up on my news feed.

Now there are several eco alternatives out there from hemp waste product to wood fibre waste product and now grass. My biggest issue is the cost of these products is often so much higher than the not so eco versions like foam or XPS etc. I did not build a non supporting wall from hemp blocks as it worked out to be 5x the cost of concrete blocks which were also load bearing which in the circumstance was preferable in the end. I thought I would post the link to the new grass product just in case anyone was interested

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Sounds interesting - one assumes they would treat it in some way so that it didn’t get eaten by loir, ragondin, sanglier, or tyrannosaurs…

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Yes I would expect borax for insect, animals and fire resistance

We are currently installing this product:

Mostly 150mm thick on walls and 300mm between floors as ceilings are very high.

Accoding to their technical data rodents are not an issue…

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That is the part I may have issue with as the little criters can and do nest in most materials so using stainless steel mesh is probably the best measure you can take.

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It would seem that Gramitherm is £18.91 per square meter (including VAT) https://www.ecologicalbuildingsystems.com/product/gramitherm-sustainable-grass-insulation?srsltid=AfmBOor9DJAHq8E0YtPP7zaTNiwNMkOz1QggRaWaZ9f6Eg6B4fBjXHFu for a 100mm thickness giving an R value of 2.44 and so a 200mm thickness would be £37.82 per square meter giving an R value of 4.88 whereas using Glasswool at 200mm thick to give an R value of 5 is £5.87 a square meter at today’s exchange rate. (Bricot Depot price)
That makes the Gramitherm 6.44 times more expensive.
That’s a lot to pay for being eco friendly.

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Although I dont like glass wool as I have had to remove lots of it over the years as you buy it at 100mm and a few years later its about half of that. If it gets damp it collapses even faster, at least rockwool doesnt have either of those problems and can stop the spread of fire. Years ago I used “eco” friendly, made from plastic bottles and bags insultaion, I checked this a while ago when running a cable and its just dust now, like an old plastic bag after a few years it just fractures to dust, lesson learnt.

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We have had rodents making nests in our polystyrene block insulation in the garage roof, so I’d be of a similar mind.

I have metres and metres of rodent mesh around the eaves etc. Just missed I spot and a loire got in! No more though. I have some more to do at the back bedroom when I re chaux the wall. The snake keeps guard over that part for now.

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Yes, I agree that Rockwool is better, especially in view of its fire resistance properties.