Peak Sawdust

Adam1 · Post by **Adam1** » 26 Aug 2008, 21:03

RenewableCandy wrote:Will shredded paper work with composting loos? I mean, how l-o-n-g is it going to be before we ever reach Peak Paperwork ?

Or peak loo paper?

RenewableCandy · Post by **RenewableCandy** » 26 Aug 2008, 21:26

My grandmum had a huge stash of loo-roll in her airing cupboard. She was a woman ahead of her time...

Pani Kova · Post by **Pani Kova** » 26 Aug 2008, 22:01

Yup, and my nana had about 200 bars of soap stashed alongside the scores of rolls of toilet paper. In fact, on her death, her estate largely comprised bog roll and soap. Cheers nana!

Adam1 · Post by **Adam1** » 26 Aug 2008, 22:02

RenewableCandy wrote:My grandmum had a huge stash of loo-roll in her airing cupboard. She was a woman ahead of her time...

The mind boggles. Why the airing cupboard? Did they double up as insulation while they were waiting to be used?

RenewableCandy · Post by **RenewableCandy** » 26 Aug 2008, 22:08

Adam1 wrote:
RenewableCandy wrote:My grandmum had a huge stash of loo-roll in her airing cupboard. She was a woman ahead of her time...
The mind boggles. Why the airing cupboard? Did they double up as insulation while they were waiting to be used?

It was next to the bathroom and it was also the warmest/driest room in the house.

biffvernon · Post by **biffvernon** » 27 Aug 2008, 08:16

kenneal wrote:Biff, I had heard that you need heart of oak for smoking, not sapwood. Do you know if that's true?

That makes sense. The tannins are in the heartwood. If you tried smoking with only sapwood the result might be poor.

emordnilap · Post by **emordnilap** » 11 Jan 2009, 14:23

biffvernon wrote:If you mix sawdust with water and lime (the white powder from the builders' merchant) and then press it onto the internal walls of your dwelling, it dries and sets to form an insulating plaster. Choose the coarsest sawdust - stuff from planers and thicknessers is better than actual saw dust - as you get more airspaces so better insulation. Messy, fun, cheap and effective.

Is that what they call hydrated lime? What sawdust/lime ratio do you use? Is the sawdust damp to start with? What about insects/rodents? Any other info you can give? Presumably you'd have to wear a mask and gloves when doing this work.

I'm considering using this as a method of insulation and the more info I get the better.

biffvernon · Post by **biffvernon** » 11 Jan 2009, 14:41

Hydrated lime is the white powder you get from the builders' merchant when you ask for a bag of lime. Chemically it is calcium hydroxide. It's made by heating limestone, calcium carbonate till it turns into calcium oxide and then adding a little water, just enough to turn it into dry calcium hydroxide but not too much or you get wet calcium hydroxide known as lime putty. When you use it to make mortar, exposing it to air in a damp environment, it gradually absorbs CO2 from the air and turns into calcium carbonate.

Not sure about exact ratio, emordnilap. I used a wheelbarrow full of sawdust with a shovel full of lime. Bit of trial and improvement. Too little lime and the stuff won't stick together, too much and there won't be so much airspace so it will be a worse insulator. You need just enough to get a workable mess. Think wheetabix.

I mixed it dry and then added water. I can't see it being tasty to furry creatures so no more vulnerable than other building materials.

Mask, or stand upwind when mixing the dry stuff. Gloves, lime is caustic, like ordinary cement. Makes tender skin raw after a while so best to wear gloves but I wouldn't get paranoid about it.

When applying it to a wall it's like plastering but a bit more squeezing it onto the wall rather than just sliding the plasterer's float about. Do a bit at a time starting from the bottom of the wall and build upwards.

emordnilap · Post by **emordnilap** » 12 Jan 2009, 15:45

Great post, biff, thanks. The thing is about 'hydrated' is there's another kind of lime called 'hydraulic'; must look up the difference.

So how big an area did you do? How thick/high was the layer? Are you pleased with the result? Do you think it works better than other forms of insulation?

Post by **kenneal - lagger** » 12 Jan 2009, 16:01

Hydraulic lime is a cross between lime and cement. There is some clay in the lime when it's fired which, when mixed with water again, takes up the water to give a quick set, hence hydraulic. The lime part then carbonises over a longer period as ordinary lime does.

There are three grades of hydraulic lime, depending on the clay content, getting stronger with increasing clay.