[TheForge] Re: rFoil vs Fibreglass Insulation

Wed Jan 22 20:31:02 2003

From looking at http://www.we-intl.com/rfoil_garage.html, I think this stuff
is a rip and their information looks like the same stuff their peddled with
snake oil.  If the only thermal energy you want to contain or resist is
radiant, maybe it will work.  The trouble is we want to have warm air on our
front and back sides.  That means convection and probably conduction has to
happen.

U get what U pay for.  R value costs money but that's what works as long as
it's dry and stays in place.  If your insulation gets wet from water/roof
leaks or condensation the R value goes away until it gets dry.  If your
insulation is from an inert gas that disappears over time your R value goes
away.

Buy the right insulation for the right location.  If it won't resist
moisture penetration, protect it on the warm (humid) side with a vapor
barrier.

Just and FYI:  When we do thermal calculations for heat loss/gain, we use
the thermal conductivity of each building component.  From that we can
calculate and graph the temperature gradiant across the wall to see what is
really happening and where the dewpoint will actually occur.  We want it in
the insulation.  If it's on the surface or inside a material that is porous,
you get wet whatever.

BTW ... I see they say they have some sort of bubble wrap that has a good R
value.  Unless the bubbles are microscopic, I doubt it.  That's because the
air inside the bubble starts moving and then .... you got it - convection
across the bubble then conduction out the otherside.

Walt
(just an architect too)

-----Original Message-----
From: Patricia J. Stanley <[email protected]>
To: [email protected] <[email protected]>
Date: Tuesday, January 21, 2003 10:12 PM
Subject: [TheForge] Re: rFoil vs Fibreglass Insulation

>Getting ready to insulate the addition on  my shop(post frame
construction).
>Has anyone used rFoil Reflective insulation? Any feedback?
>
>See www.we-intl.com/rfoil
>
>Phil
>Jordan Forge
>
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