Has anyone used Matte R-max plus3 insulation

[BusZen2003]

Just wondering if this is good for Skoolie insulation. It seems to show a better r rating than EPS or XPS

[john61ct]

Best for extreme winter is mostly polyiso but a thin skin of xps on the freezing side.

[JDSquared]

Originally Posted by BusZen2003

Just wondering if this is good for Skoolie insulation. It seems to show a better r rating than EPS or XPS

I think that's the stuff I was looking into. And it needs like a 3-inch air gap to get that insulating property. They use it against the stud wall in buildings, they don't fill the cavity with it.

[john61ct]

If you're talking about Mylar based reflective barriers

that is not insulation at all, pretty much a waste of time and money in a mobile context

[JDSquared]

Originally Posted by john61ct

If you're talking about Mylar based reflective barriers

that is not insulation at all, pretty much a waste of time and money in a mobile context

We aren't.

[john61ct]

OK looked it up, polyiso good stuff but forget the brand generic is fine.

Highest R-value per thickness, good stuff, but see above wrt needing a layer of XPS for extreme cold.

Would not bother with thicknesses under 2-3" total myself, but depends on context and goals.

Getting a completely well sealed vapour barrier is critical, more so than R-value.

Also eliminating thermal bridging.

Spray foam is a great tool for both in combination.

[musigenesis]

Originally Posted by john61ct

Best for extreme winter is mostly polyiso but a thin skin of xps on the freezing side.

Polyiso has its nominal value of R-6.5 per inch at higher temperatures; this declines at temperatures below 60F (most insulations have a declining R-value with higher temperatures, which makes polyiso fairly unique). But its low-temperature R-value is still about as good as EPS or XPS, so it's still fine for low temperatures but is best-suited for warmer weather.