Vermicrete or Concrete slab with Cal sil?

[kallipigous]

Does it make any difference adding vermicrete under 2" cal sil boards or should I just create the concrete slab instead?

Is it overkill?

Regards

Toby

[okn]

Re: Vermicrete or Concrete slab with Cal sil?

Probably would make a slight difference, to have more insulation. The 2 inches of CalSil is the 80-90% solution. I have 3 inches of CalSil and I would say that's about 90-95% of as good as it gets. That's my non scientific 2 cents.

[kallipigous]

Re: Vermicrete or Concrete slab with Cal sil?

Ok well maybe I'll grab 3" instead. Seems a lot easier that mixing up 4" of Vermicrete and the concrete slab should provide a flatter surface I'm thinking.

I'm ordering the Thermo Gold. I take it that will hold up the brick dome fine? I did see some concerns in one thread that it was compressible but then many others seem to have used it so I'm assuming it's fine.

I see you're not far from me (I'm in Santa Clarita). Can I ask where you sourced your Cal sil?


Cheers

Toby

[RandyJ]

Re: Vermicrete or Concrete slab with Cal sil?

I have not fired my oven yet but I went with 4" of calsil board under my oven. I am glad I did not mess around with the vermicreete that seamed like a pain to do. I am excited to see my results. I am also filling my enclosure with vermiculite over the top of the 3"of blanket.

Randy

[okn]

Re: Vermicrete or Concrete slab with Cal sil?

I bought Insblock 19 from Harbison Walker. I think you made a good choice to go 4 inches. IMHO that's as good as it gets. Your insulation on top sounds good to. Then only other pivotal part for insulation is to have a well insulated door. The door makes a huge difference.

[kallipigous]

Re: Vermicrete or Concrete slab with Cal sil?

Yes I've been thinking about the door. I was going to take a look at the cal sil board when it comes and see if there are enough cuts left over to use that as the fill. I think 2" of insulation with metal and wood either side should do the trick.

[RandyJ]

Re: Vermicrete or Concrete slab with Cal sil?

Yes I have plenty left to do a door. I have one full box still so 2- 2'x 3'sheets of 2" so I am planning to do a 4" door.

Randy

[kallipigous]

Re: Vermicrete or Concrete slab with Cal sil?

ok I'll plan on that

[RandyJ]

Re: Vermicrete or Concrete slab with Cal sil?

I don't know where you plan to get your insulation fom but I got mine from McGills Where house. It was pretty reasonable. Good luck.

Randy

[kallipigous]

Re: Vermicrete or Concrete slab with Cal sil?

International Insulation Distributors and Custom Fabrication

They have the Thermo Gold at a reasonable price. It'll go down and collect it next week.

[Gulf]

Re: Vermicrete or Concrete slab with Cal sil?

Kallipigous,
I used DI for my insulation, as well. Then, they were only on located in some gulf states and a little up the east coast. I read where they have been doing some acquisitions to the west. I found them to be reasonably priced and very knowlegeable.

Randy,
I have a 4" CalSil, 26 guage metal clad door. It works great as an insulator. But, it is a little on the "heavy" side. I have enough CalSil to build a 2" version. Which, I plan to do as soon as it comes up to the top of the prioriaty list. My list, that is . SWMBO's list takes prority over mine .

[RandyJ]

Re: Vermicrete or Concrete slab with Cal sil?

Thanks gulf. I have enough left over to do both a 4" door and a 2" as well. I can see where that might be a good idea. One for max heat retention, and one for ease of use.

Randy

[kallipigous]

Re: Vermicrete or Concrete slab with Cal sil?

I'm sure given that it's stopping hot air and radiated heat rather than bricks right up against the insulator 2" will be fine.

That's my uneducated guess anyway.

[RandyJ]

Re: Vermicrete or Concrete slab with Cal sil?

I am sure that 2 " is probably good enough for most of the time but when it is -20F here if I wanted to bake bread then 4" is maby a better way to go. Plus I already have the insulation so no loss there. If I got one more box I could have done 6"and still done a door.

Randy

[kallipigous]

Re: Vermicrete or Concrete slab with Cal sil?

Di took over Pacific Insulation here in socal so that's why I went to them. It took some detective be work but I found them.