Diathonite questions

[charlieroper]

We're meant to be using a diathonite thermactive to insulate the walls of our old stone barn we are rennovating. The architect is dead keen on it and from what I read it is great (if expensive and hard to apply). I can't however find anything that goes into any detail about two points:

1) Can you treat it like a normal plaster wall for hanging pictures/putting up shelves? I'm concerned that it's spongy makeup might make it disintegrate if we did. The builder has suggested pattressing with insulation board where we might want to hang heavy things but we want to have flexibility in the future given we don't really own any art now but might want to in the future
2) Given it is "breathable" it needs to be painted with "breathable" paint however there seems to be no universally accepted view of what that actually means. Clay based natural paints seem to be compatible but cost an absolute fortune and we don't want to spend a load of money on the insulation to then ruin it with the wrong paint.

Does anyone have any lived experience of using Diathonite Thermactive and can answer these questions?

[Redbeard]

I have never used Diathonite but I have done a lot of wood-fibre, which also needs 'breathable' paint. Various sources out there - it does not have to be clay-based, but also 'Contract Matt emulsion'. Just avoid anything with 'vinyl' in its name.

 

Lois Hurst at luneretrofit.com will certainly have 'lived experience' of Diathonite. I don't know if she gives the advice you need, but it's worth a try.

 

You say:

10 minutes ago, charlieroper said:

Can you treat it like a normal plaster wall for hanging pictures/putting up shelves?

 

and that the builder has suggested

7 minutes ago, charlieroper said:

pattressing with insulation board where we might want to hang heavy things

 

Hmm... Well, with normal plaster and a heavy painting you'd screw-fix back to the masonry, going thro say 20mm of plaster. With perhaps 100mm of Diathonite you have looong screws and a thermal bridge. Stainless steel is less conductive (and more expensive) than mild steel.

Assuming that's with something 'green' (wood-fibre or cork, perhaps) then it's probably not a huge deal more load-bearing than Diathonite.

[jayc89]

Never quite understood Diathonite. Seems to be targeting the "vapour open" market, yet is made with NHL5, so might as well have been made with cement. 

[Joshdobbins]

I'm about to use Dyathonite Thermactive on a barn conversion near Leeds - being applied by Jordaya Contracting - at about 60mm thickness.

 

Our architect took us up to a property near Grassington who had used it and they didn't see to have any issues drilling into it to hang things. Ecological Building Systems also sent us a sample piece which we played around with and the finished product seems pretty solid, at least enough to hang a shelf off although you will end up with a bit of a thermal bridge. 

 

On the breathability of the paints. I was in a similar conundrum and reluctant to go down the clay/ lime wash options as a lot of the wall will be in an open plan kitchen, and we want something washable. We think we will go with Beeck Mineral Sillicate paint, at least the stats look good.

 

Diathonite should be going on early Jan so happy to share any feedback post then if you wan. 

[charlieroper]

Thanks @Joshdobbins - that's  very reassuring on the ability to hang things, I was wondering if plastic screws for this purpose (given they're not supporting much weight) might be a good option to prevent bridging?

On the breathability front I got the technical information which I needed (from 21 degrees which i think is the new name of Ecological Building Systems?). The paint needs to have an SD (steam diffusion) value of 0.0225 or lower for the diathonite to function properly. I did some research as to paint brands/products that fit this criteria, how much they cost, and what their advertised coats/coverage are to give a cost per m2 of finished wall in each case. This is not definitive but might be of some use nonetheless....

[Redbeard]

21 Degrees is the new name for Green Building Store.