On Jun 30, 3:00�pm, Joe wrote:
I have rock wool insulation stapled to the rafters of my cape cod
built in 1952. It's in pretty good shape but I'm not sure if it should
be replaced or augmented. My 2nd floor is always a degree or two
colder than my 1st floor in the winter so I decided I'm in need of
some insulation. I checked and noticed that where the dormers were
added there is a lack of insulation. A handyman I had doing other work
on my house said that the wool insulation is better than the
fiberglass and I should keep it and just add some insulation to the
knee joints near the dormers where it is lacking and that should be
enough. I'd like to take care of this correctly so I'm wondering what
the conventional wisdom of rock wool insulation is. Is there an R
value for it?

appears rock wool and fiberglass are same per inch, around 3

closed cell foam is over r6 per inch.

i would pull up the rock wool and replace with closed cll foam

wrote:

On Jun 30, 3:00�pm, Joe wrote:

I have rock wool insulation stapled to the rafters of my cape cod
built in 1952. It's in pretty good shape but I'm not sure if it should
be replaced or augmented. My 2nd floor is always a degree or two
colder than my 1st floor in the winter so I decided I'm in need of
some insulation. I checked and noticed that where the dormers were
added there is a lack of insulation.

appears rock wool and fiberglass are same per inch, around 3

closed cell foam is over r6 per inch.

i would pull up the rock wool and replace with closed cll foam

Only if it's completely covered with plaster or drywall, right?
Because foam burns like crazy and must never be left uncovered. I
don't think any codes allow it to be left exposed. If covering the
insulation isn't possible or practical, there's dense fiberglass, also
rated about R-6 per inch, that's safe to leave uncovered.

On Jun 30, 9:17Â*pm, "larry moe 'n curly"
wrote:
wrote:
On Jun 30, 3:00�pm, Joe wrote:
I have rock wool insulation stapled to the rafters of my cape cod
built in 1952. It's in pretty good shape but I'm not sure if it should
be replaced or augmented. My 2nd floor is always a degree or two
colder than my 1st floor in the winter so I decided I'm in need of
some insulation. I checked and noticed that where the dormers were
added there is a lack of insulation.

appears rock wool and fiberglass are same per inch, around 3

closed cell foam is over r6 per inch.

i would pull up the rock wool and replace with closed cll foam

Only if it's completely covered with plaster or drywall, right?
Because foam burns like crazy and must never be left uncovered. Â*I
don't think any codes allow it to be left exposed. Â*If covering the
insulation isn't possible or practical, there's dense fiberglass, also
rated about R-6 per inch, that's safe to leave uncovered.

Spray in place closed cell foam is superior because it expands and
seals all the tiny gaps, holes around electric outlets etc.

Rooms will be noticeably quieter and more comfy.

if your going to all the work to replace the insulation you might as
well go with the best!