Sorry - another Vermiculite Question

[thebadger]

Gang,

I did search the threads first and didn't see answers to my question(s).

Background
I'm picking up supplies and my local garden store has both Perlite and Vermiculite (same price $19.99/ 4 cu ft).

The Perlite says "horticultural" grade and the granuals look like pictures I've seen

The Vermiculite has a "check box for horitcultural grade and a check box for fine med course - but nothing is "checked" (the worker says it's "med/course not fine") but the vermiculite looks like it is very small flakes - almost like sand but flatter. I picked up 4 bags but can exchange if needed...

Question(s)

1. Are the size of Vermiculite flake okay/does it matter?
2. Should I just go with perlite instead (same price and they have plenty of both)
3. Is one safer vs the other (I guess a non issue "after" it's installed?)
4. Can I use a "cheap" drywall mask or should I get a ~$25 respirator?

Thanks
Dick

[asudavew]

Re: Sorry - another Vermiculite Question

I used both.
Perlite and Verm.

The verm. was so much easier to work with than the perlite.
Hands down.
I will NEVER play with perlite again!
It was dusty, fine, and blew everywhere~!

My opinion....

As you were!

DAve

[gjbingham]

Re: Sorry - another Vermiculite Question

Try a search on this forum for coarse verm. and one for fine verm. There's been several discussions regarding your question. I believe the medium was generally found the easiest to work with, but don't quote me on that.

I used coarse, without any major issues. The grain size was bb shot size up to twice that size - maybe 4 - 5 mm.

[david s]

Re: Sorry - another Vermiculite Question

I agree ,vermiculite is better to work with, and prefer to use it, but perlite has slightly better insulation value.

[thebadger]

Re: Sorry - another Vermiculite Question

Gang,

I did do a search and only found one post about fine vs. course vermiculite. The preference was for for course but nothing "bad" was said/or suggested not to use fine. I want to use this to make my 5-6 inch insulating hearth (going a little thicker) but didn't want to use the wrong stuff. I've attached some pics... Maybe this stuff is "okay" - I just started to question when I saw the different grades on the package (none are marked).

Is this okay to use? I'm assuming the 5 to 1 ration is still okay with this type. Again, the place I bought it from has perlite that looks like the pictures I've seen posted and I can easily exchange it.
Let me know.

Thanks
Dick

[Dutchoven]

Re: Sorry - another Vermiculite Question

I will suggest the use of vermiculite...probably coarse...only because it has a tendency to break up a bit with mixing...perlite is what I used and it blew around horribly and was difficult to get properly mixed...
Best
Dutch

[gjbingham]

Re: Sorry - another Vermiculite Question

I think it will be fine. I like the idea of six inches of floor insulation too.

[thebadger]

Re: Sorry - another Vermiculite Question

George

Thanks - I'm doing the 6" insulating hearth for two reasons - extra insulalion and extra height.

Does everyon agree that the 5 to 1 ration is still okay for this "finer" Vermiculite (I'm assuming this is a finer grade)?

Given a 5 to 1 are there any guidelines (in parts) for the water i.e., 1/2 part water? I know it says "an oatmeal consistency..." but I've made some pretty soupy oatmeal in my day.

Thanks for the advice...

Dick

[thebadger]

Re: Sorry - another Vermiculite Question

Gang,

I just called a local pool supply place - he was very familiar with vermiculite as that's what he uses in pool construction.

He told me it's usually fine like sand - but that's not what I've seen in the pictures on the forum???? Hence my confusion/concern.

I am going to order the FB board but would still like to put a small layer 2-3" of vermiculite/concrete down first.

What does everyone think?

Thanks
Dick

[asudavew]

Re: Sorry - another Vermiculite Question

I believe some of the pool vermiculites are coated with silicon, which can create a problem with blending it with cement and water.

Try a local plant nursery and get medium or large course vermiculite.

I got 4 cubic foot bags at my local nursery for about $23.00.

They did have to order it though.... but they received it with their normal delivery.
(Translation - 4 day wait.)

Hope this helps!

Dave

[Frances]

Re: Sorry - another Vermiculite Question

When I did my vermiculite layer, I got worried because mine was very coarse and everyone was using fine grain stuff... maybe its another of those things where it doesn't really matter much either way so long as you get the hydration and concrete proportion right?

[thebadger]

Re: Sorry - another Vermiculite Question

That's kind of my issue.

What I have is very fine - almost like sand. To be on the safe side I'll probably get the Isol board but still want to pour a smaller insulated hearth...

My main question is should the "fine" stuff be okay? 5 to 1 ratio as well?

Thanks
Dick

PS - George - I did see your response but want to get a consensus. This is something I can't change once my floor is down...

[gjbingham]

Re: Sorry - another Vermiculite Question

Otter,
You can't hurt my feelings. I would do the same! I thought you said you could take it back and exchange it?

[thebadger]

Re: Sorry - another Vermiculite Question

George,

Thanks!

I can - and I think I will take it back for the perlite... I'll probably put down a 3 1/2 inch layer (extra height and insulation) and then 2 inches of Iso board on top... That should bring my oven height to ~43".

Thanks
Dick

[gjbingham]

Re: Sorry - another Vermiculite Question

I like that! Lots of insulation under the floor. Great idea!