Concern about mold

[kebwi]

As I have been building my oven in the damp northwest (especially the fall and winter), I have already had mold issues in that my masonite arch forms have become quite fuzzy. I imagine that the rather damp plywood that has been the floor protection for the last four months is probably pretty moldy too, but I'm not too worried about it since the inside of the oven is going to be virtually sterlized anyway.

What I am a little concerned about is the fluffy InsWool insulation. I'm not using a blanket, I'm using loose "bulk" (with some sort of wire mesh to hold it in place, I haven't quite figured this out). I'm worried that it will become damp and totally run through with mold before I get a chance to fully enclose it, either in a vermicrete dome or in a "building" subsequently filled with loose vermiculite.

Any thoughts on this? Does it not matter if it gets totally moldy before I put it a vermicrete dome over it? What if I do the building, roof, and loose vermiculite? In that case it is never truly sealed and will almost certainly be damp forever, or every winter.

[Wiley]

Re: Concern about mold

Kebwi,
As a fellow resident of the Pacific Northwest I am familiar with the mold/algae/fungus growth of which you speak. I suspect that the insulation is inorganic (ie akin to spun ceramic... kaowool), if kept clean such are not a food source for such organisms. Yes, lichen grows on barren clean rock but hopefully you will finish before that occurs. Lichen feeds on rock decomposing into dirt, primarily feldspar into clay minerals if I remember correctly something I once read and that takes significant time.

All that being said I would endeavor to keep it as dry as possible at the same time trying not to create an environment condusive to growth. A plastic sheet might seem ideal until on a hot day you get condenstion and higher temperatures from the greenhouse effect of the plastic sheet. I have friends who have air dried wood successfully out-of-doors by good airflow and space between the weather proof layer and the top layer of wood. And of course "ricking" the layers of wood.

Rainwater being a "scrubber" of the air it falls thru is not clean at all and should you get the insulation soaked thru with rain water I would (personally if it were mine) give the whole a good spraying with a clorox water solution. I'm saying "soaked" not "dampened". If soaked wouldn't be any wetter and by doing so it at least wouldn't be growing anything.

Glass blower friends have told me that typically they wet kaowool with water before working with it to keep the errant broken fibers from becoming airborne. That may be fine but then one must dry it out which again takes time. I'm not familiar with the insulation you are using, is it hollow tubes (like fiberglass insulation) or solid strands (like kaowool)? Once wet fiberglass will never fully dry out as the tiny tubes suck water thru capilary action (which then becomes trapped).

In the end it probably doesn't matter much if it gets a little bit moldly, your "totally run thru with mold" would be something I would do alot of work to avoid.

Hope this has helped,
Wiley

[Neil2]

Re: Concern about mold

No structure can be made absolutely waterproof. Design your enclosure so that there is reasonable ventilation to enable the insulation layer to dry out if water gets in.

With an enclosure, you can skip the wool insulation or blanket . Just use straight vermiculite.

[kebwi]

Re: Concern about mold

I'll take all of that under advisement. I'm still trying to figure out how to build a "building", walls and roof.

Thanks.