Has Anyone here tried this insulation?

[Yuuyia_Takahashi]

Hey everyone,

Wasn't sure where to put this thread so it ended up here...


While researching insulation, I came across "Mineral wool". While there are several different brandnames of the stuff, I was curious if anyone has used it instead of the typical "Pink board"...

The reasons I ask is this...

1. It comes in both boards, and batts.. for ease of installation.
2. It has the same R value as pink board in a 2in thickness.
3. Doesn't absorb moisture, but is still breathable. (mold and mildew resistance)
4. Is fire retardant up to around *1300 F.
5. Highly sound dampening.
6. It's a "green" product seeing as its made from recycled stone

The only downside I believe is the cost... ($#!T's pretty spendy.) and I know nearly everyone who's doing a bus is doing it from a budget standpoint.


Feel free to discuss

 

[Twigg-SKO]

Hey everyone,

Wasn't sure where to put this thread so it ended up here...


While researching insulation, I came across "Mineral wool". While there are several different brandnames of the stuff, I was curious if anyone has used it instead of the typical "Pink board"...

The reasons I ask is this...

1. It comes in both boards, and batts.. for ease of installation.
2. It has the same R value as pink board in a 2in thickness.
3. Doesn't absorb moisture, but is still breathable. (mold and mildew resistance)
4. Is fire retardant up to around *1300 F.
5. Highly sound dampening.
6. It's a "green" product seeing as its made from recycled stone

The only downside I believe is the cost... ($#!T's pretty spendy.) and I know nearly everyone who's doing a bus is doing it from a budget standpoint.


Feel free to discuss

Can you provide a link please?

The reason I ask is that we have discussed this type of product before. While it is true that the fibers themselves do not absorb water, in most cases the batts or boards absorb a great deal of water, so I was wondering if this were somehow different.

 

[Yuuyia_Takahashi]

Can you provide a link please?

The reason I ask is that we have discussed this type of product before. While it is true that the fibers themselves do not absorb water, in most cases the batts or boards absorb a great deal of water, so I was wondering if this were somehow different.

Now I feel a bit dumb... the one time I didn't bother using the search..

https://www.rockwool.com/products/comfortbatt/

This is the product that the technical service lady that I spoke with recommended when I told her was I was doing and what my concerns were... However there are numerous products that they offer that would be applicable.

They will also make custom products upon request, but im sure the price of that would be astronomical.

 

[o1marc]

IINM rockwool is used more often in high heat applications, it's what I use to line my powder coating ovens with so it doesn't break down like batt insulation does subjected to 400° for hours on end.

 

[Yuuyia_Takahashi]

IINM rockwool is used more often in high heat applications, it's what I use to line my powder coating ovens with so it doesn't break down like batt insulation does subjected to 400° for hours on end.

Yeah, I read through a multitude of their applications on their site and though “Oh! This might be good for a skoolie..” spent a bit of time on the phone with a rep and got a few recommendations. While a skoolie isn’t a powder coating oven, it behaves like an oven here in the south.. soooooo

Like I said it was just a thought cause it seems pretty rad (aside from the cost of course)

 

[Godspyro]

I have half a bag of ROXUL at home, used it around a chimney pipe.
I can get it wet or pretty much anything else with it if you want some feedback. just let me know what you want to test.

 

[Yuuyia_Takahashi]

I have half a bag of ROXUL at home, used it around a chimney pipe.
I can get it wet or pretty much anything else with it if you want some feedback. just let me know what you want to test.

It’s somewhat dependent on which particular one you have but the only general test I’d say would be that if you have, like a rubber-mate style tote, fill it about half way with water, and stand a batt up in it long ways. Let it set an hour or two. Then pick it up and see if it drains big time, or is it’s majoritivly hydroscopic

That’s the only thing I could think of

 

[o1marc]

Stuck a piece of rock wool in a water dish, sucked up water like sponge.

 

[Tango-SKO]

Any kind of fibers, even if they are hydrophobic, will act that way by virtue of the structure. Steel wool will hold water. And the finer the fibers, the more it holds.

 

[o1marc]

Any kind of fibers, even if they are hydrophobic, will act that way by virtue of the structure. Steel wool will hold water. And the finer the fibers, the more it holds.

It didn't just hold it, it sucked it right up wicking up an inch over the water level.

 

[Twigg-SKO]

It didn't just hold it, it sucked it right up wicking up an inch over the water level.

That's capillary action. Normal and expected.

 

[Tango-SKO]

Same thing that makes factory installed fiberglass a pi$$ poor choice to put inside a metal can. Any condensation just hangs around and makes rust and mold.

 

[brokedown-SKO]

So educate me. What insulation should I be putting in the ceiling/walls? Spray in foam insulation? I'm going to be at that stage soon and the more things I get right the less things I'm doing twice.

 

[Twigg-SKO]

So educate me. What insulation should I be putting in the ceiling/walls? Spray in foam insulation? I'm going to be at that stage soon and the more things I get right the less things I'm doing twice.

Spray foam or Iso Foam Board are the usual products used.

 

[Tango-SKO]

When considering spray in foam...make sure it is closed cell. There are some people spraying open cell which is just another sponge.

 

[RRRVBUS]

Seems to my feeble brain cells that spray in would be about the best you could do. Doesn’t it get in everywhere and expand and seal? It’s my first choice but the budget will make the final decision.

 

[PNW_Steve]

Seems to my feeble brain cells that spray in would be about the best you could do. Doesn’t it get in everywhere and expand and seal? It’s my first choice but the budget will make the final decision.

Yes it does. You are not as feeble as you claim

I had my first bus spray foamed. The difference in the driving experience between driving the bus to the insulation shop and driving it home was amazing.

It was August and the drive home with the bus insulated was soooo much quieter and cooler than the drive to the insulation shop.

It also sealed any air infiltration.

I just finished wiring a bus for another gent here in town and much of the time we were working inside the bus it was 20F-35F outside. He had about 2" of spray foam. With minimal or no heat running we stayed quite comfortable.

My $0.02.... I cannot see myself NOT putting spray foam in my bus.

 

[Yuuyia_Takahashi]

Seems to my feeble brain cells that spray in would be about the best you could do. Doesn’t it get in everywhere and expand and seal? It’s my first choice but the budget will make the final decision.

You would be correct. It does get everywhere that you apply it, and it does expand to seal all crevasses. Like stated above though, use closed cell.

ALSO, there is some fine print associated with expanding foam. Certain chemical compositions of it react poorly with exposed steel, causing a chemical reaction that also causes rust and deterioration.

My opinion is that if you are going to use spray foam, you better make damn sure that any metal that you plan on letting it come in contact with has been properly coated. Either by primer, paint, seam sealer, whatever.... just don't willy-nilly spray it anywhere that you can think of to spray it.

Also remember that the bus bodies are designed to have drainage points. (just like your car does) so don't clog them all up or else whatever moisture accumulation you do get won't have anywhere to go in order to dry out.

 

[PNW_Steve]

ALSO, there is some fine print associated with expanding foam. Certain chemical compositions of it react poorly with exposed steel, causing a chemical reaction that also causes rust and deterioration.

My best understanding is that this is an issue with single part foam. It depends on air contact to cure and in its uncured state it can be corrosive.

I do not believe that the two part, closed cell spray foams that we are using suffer from this issue.

Do we have any foam experts in the house?

 

[Yuuyia_Takahashi]

But yeah, the reason that I brought up the mineral wool was this.... (long explanation inbound, sorry)


The busses like any car have holes here and there in strategic areas to allow for water drainage. This is a good thing.

They then toss in some insulation to make it tolerable for passengers. This is also a good thing.

The first problem comes from the density, and material of the insulation.
(It comes from whatever brand name agrees to a contract helping the bus maker maintain a certain price point) So, while 'acceptable' it's pretty much worthless to us as Skoolies.

The second problem is that the cheap, sparse stuff they use ends up holding quite a bit of moisture. thus causing rust.

Since no mater what we do condensation will be a regularity heres how I thought to deal with it.


First thing that needs to be done is to obviously Coat all exposed metal with some sort of chemically bonded base layer to help prevent rust.

In theory a completely air tight space would be the solution, but the likelihood of having an air tight bus is beyond most of us. So I figure that if an insulation were to be used that 1. Is dense enough to reasonably stop most of the airflow, 2. Resists the accumulation of moisture, 3. Still has the OEM ventilation points to allow for evaporative vapors to escape when the ARE present, 4. Has a high resistance to mold/mildew, and 5. Provides an adequate R value. Then it would be a prime candidate for a conversion.

The particular products that I got directed to from the Rockwool representative also have the added benefit of acoustical dampening, and extreme heat resistance.