My last question before I get started with insulating my crawl space.
Remember this is my first time doing this. What does the "R" mean for
insulation. I was going to insulated my crawl space with fiberglass
insulation but a man from the big orange box told me that for a crawl
space I could use (i forgot the exact name) styrofoam and glue it to the
walls and it would have an R10 rating (or something like that). What did
he mean and is styrofoam just as effective as insulation (in Colorado) for
keeping the heat in?

"cece e." wrote in message
news:a7e539f1bc9dfc6800930e84a7875f5d@homerepairli ve.com...
My last question before I get started with insulating my crawl space.
Remember this is my first time doing this. What does the "R" mean for
insulation. I was going to insulated my crawl space with fiberglass
insulation but a man from the big orange box told me that for a crawl
space I could use (i forgot the exact name) styrofoam and glue it to the
walls and it would have an R10 rating (or something like that). What did
he mean and is styrofoam just as effective as insulation (in Colorado) for
keeping the heat in?

R is for resistance to heat movement. Some info here
http://www.rvalue.net/

Styrofoam is about R4 per inch, same with expandable polystyrene.

On Wed, 12 Jul 2006 03:30:45 GMT, "Edwin Pawlowski"
wrote:


"cece e." wrote in message
news:a7e539f1bc9dfc6800930e84a7875f5d@homerepairl ive.com...
My last question before I get started with insulating my crawl space.
Remember this is my first time doing this. What does the "R" mean for
insulation. I was going to insulated my crawl space with fiberglass
insulation but a man from the big orange box told me that for a crawl
space I could use (i forgot the exact name) styrofoam and glue it to the
walls and it would have an R10 rating (or something like that). What did
he mean and is styrofoam just as effective as insulation (in Colorado) for
keeping the heat in?

R is for resistance to heat movement. Some info here
http://www.rvalue.net/

Styrofoam is about R4 per inch, same with expandable polystyrene.


And here I always thought it meant "Rob". The higher the R value the
more money they ROB from your wallet.

Styrofoam is R4-4.5" Blue or pink foamboard is R5" Foil faced
Polyisocyanurate foamboard is R7.2" R value is resistance to heat flow,
foam costs more, in certain areas it is better where area to insulate is
minimal, it also provides a vapor -air infiltration barrier.

m Ransley errs again:

Styrofoam is R4-4.5" Blue or pink foamboard is R5"

Same thing. All R5 per inch. Open cell expanded polystyrene
(white coffee cup material) is R4 per inch...

Foil faced Polyisocyanurate foamboard is R7.2"

These days, it's often stamped "R6.8" (per inch.)
Add about R3 per foil, if the foils are exposed.

Nick

Nick, White Styrofoam is not R5", extruded polystyrene, the pink Owens
Corning or blue Dow is R5" . White Styrofoam board is sold just like R5
extruded polystyrene board, in the same manner, but is inferior in R
value, workability and stability.

Polyisocyanurate foilfaced newly used rating of 6.7"-6.8" is the aged
or mature R value after R 7.2" polyiso outgasses.

Perhaps you could provide us with some detailed mathematicals of your
opinion.

Nick, foilfaced does not increase R value by 3R per foil, or R6 for
both side, please provide proof of your statement. At most it
contributes R-.5, if that.

wrote in message

Same thing. All R5 per inch. Open cell expanded polystyrene
(white coffee cup material) is R4 per inch...

That would be closed cell.

"cece e." wrote:

My last question before I get started with insulating my crawl space...
What does the "R" mean for insulation.

Resistance to heat flow. Specifically, Ohm's law for heatflow says I = E/R
Btu/h, where E is an F temp diff and R is the R-value of 1 square foot of
insulation. For A square feet, multiply the heatflow by A.

For instance, a 2'x8' R5 Styrofoam (vs R4 beadboard) wall that's 70 F on
one side and 30 F on the other will have I = (70F-30F)2'x8'/R5 = 128 Btu/h
of heat (38 watts) flowing through it.

Nick

R is the fraction of heat loss compared to an air gap the same thickness.
So R-19 insulation will conduct 1/19 as much heat as an air gap the same
thickness. If you place two pieces of insulation on top of each other you
can add the R value. For example two 6" fiberglass bats (R-19 each) equals
R-38.


"cece e." wrote in message
news:a7e539f1bc9dfc6800930e84a7875f5d@homerepairli ve.com...
My last question before I get started with insulating my crawl space.
Remember this is my first time doing this. What does the "R" mean for
insulation. I was going to insulated my crawl space with fiberglass
insulation but a man from the big orange box told me that for a crawl
space I could use (i forgot the exact name) styrofoam and glue it to the
walls and it would have an R10 rating (or something like that). What did
he mean and is styrofoam just as effective as insulation (in Colorado) for
keeping the heat in?

"cece e." wrote on 11 Jul
2006:

I was going to insulated my crawl space
with fiberglass insulation but a man from the big orange box
told me that for a crawl space I could use (i forgot the exact
name) styrofoam and glue it to the walls and it would have an
R10 rating (or something like that). What did he mean and is
styrofoam just as effective as insulation (in Colorado) for
keeping the heat in?

We're talking two different strategies for insulating a crawl space
here, I believe. You intended to put fiberglas batts between the
floor joists, and he wants you to insulate the walls of the
crawlspace.

The difference is how the crawlspace functions. In your system, it
stays close to the temperature (and humidity) of the outside air.
You open the small vent windows in the summer and block them off in
the winter. In his system, the crawlspace is insulated space --
warmer in the winter and colder in the summer. The crawlspace
isn't ventilated at all in any season.

So it seems to me you and he are talking apples and oranges. Both
methods are routinely used these days. You might want to talk to
your local utility and get their recommendation for what works well
in your area -- and, if you seal the crawlspace, how to deal with
heating equipment in the crawlspace (needs an intake air duct for
combustion air).


--
Doug Boulter

To reply by e-mail, remove the obvious word from the e-mail address

Have you tried Aluminium foil its cheaper and more practical
fire resistant and easier to install it is something you could buy from
a grocery store
R means retardant
cece e. wrote:
My last question before I get started with insulating my crawl space.
Remember this is my first time doing this. What does the "R" mean for
insulation. I was going to insulated my crawl space with fiberglass
insulation but a man from the big orange box told me that for a crawl
space I could use (i forgot the exact name) styrofoam and glue it to the
walls and it would have an R10 rating (or something like that). What did
he mean and is styrofoam just as effective as insulation (in Colorado) for
keeping the heat in?

According to zyberengel :
Have you tried Aluminium foil its cheaper and more practical
fire resistant and easier to install it is something you could buy from
a grocery store

And has _zero_ insulation value. Except inosofar as it may seal
air leaks. He's trying to insulate it, not improve its fire resistance.

R means retardant

R is insulation factor. Not fire retarding rating.
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.