We have converted a three season porch into a four season by adding a
gas stove and some new windows. Below is an unfinished basement - the
joists and subfloor are exposed. Do I gain any efficiency by
installing insulation between the joists?

Thanks in advance for any advice.

MathWhiz wrote:
We have converted a three season porch into a four season by adding a
gas stove and some new windows. Below is an unfinished basement - the
joists and subfloor are exposed. Do I gain any efficiency by
installing insulation between the joists?

Thanks in advance for any advice.

I would guess little to none.

--
Joseph Meehan

Dia duit

"MathWhiz" wrote in message
oups.com...
We have converted a three season porch into a four season by adding a
gas stove and some new windows. Below is an unfinished basement - the
joists and subfloor are exposed. Do I gain any efficiency by
installing insulation between the joists?



Sure do. How much depends on the temperature differential. If the basement
is only a few degrees cooler, there will be little savings, but if it is 20
degrees, you will retain more heat and save quite a bit. .

Sure do. How much depends on the temperature differential. If the basement
is only a few degrees cooler, there will be little savings, but if it is 20
degrees, you will retain more heat and save quite a bit. .

I'm in New England. At times, it's 50 degrees cooler.

"MathWhiz" wrote in message
oups.com...
Sure do. How much depends on the temperature differential. If the
basement
is only a few degrees cooler, there will be little savings, but if it is
20
degrees, you will retain more heat and save quite a bit. .

I'm in New England. At times, it's 50 degrees cooler.


Then you must insulate for comfort, as well as energy savings.

50 degrees cooler meaning 20f? where is you heating system and pipes,
you will save and the basement might be colder, are pipes and ducts
insulated.

Underneath the three season porch is a seperate basement (attached to
main basement via a door). There are no pipes or ducts down there
and it's unheated. When it's 0 outside in Feb, it's probably not more
than 20-30 down there. Pipes, furnace, etc, are in the main basement.

We have a natural gas stove that heats the room up in about 20 minutes.
Gets it too hot.

I live in Mass..........

If it was me, I would tear out the deck flooring and install a subfloor
with wood flooringon top of it..

But thats just me. But yeah, it would definetly be the wiser to install
an insulation. Your floor would then be warm, not as cold as
underneath. That would be terrible to have a warm room with cold feet.
:-) Save some money too.

If it was me, I would tear out the deck flooring and install a subfloor
with wood flooringon top of it..

Thanks... I wasn't clear. We have a full subfloor/floor. It's not
"deck flooring"

What I'm confused about...if heat rises and the basement is unheated
and cold, why would the floor be warmer? Do I lose heat through the
floor?

Now you're getting it. :')

Heat does not rise. Warmer air is less dense than cooler, etc., etc.

Heat is transferred by conduction, convection and radiation. You passed
on the third.

Basic physics.

Oh ... and sealing is also extremely influential, and you don't mention
insulation in the rest of the shell. Nowadays, moreso tomorrow, you
can't have too much.

HTH,
J

MathWhiz wrote:
If it was me, I would tear out the deck flooring and install a subfloor
with wood flooringon top of it..

Thanks... I wasn't clear. We have a full subfloor/floor. It's not
"deck flooring"

What I'm confused about...if heat rises and the basement is unheated
and cold, why would the floor be warmer? Do I lose heat through the
floor?

Heat will move wherever there is a difference in temperature.
Basically, heat flows from areas of warmth to areas of cold.

Many people believe that because hot air rises, most heat loss will be
through the ceiling. This is not necessarily so. Heat moves in any
direction - up, down or sideways - but always from a warm spot to a
colder one. A heated room over an unheated garage or basement will lose
heat through the floor. Similarly, heat loss can occur through walls in
the basement or crawl space, as well as above the ground. Heat moves to
the cold. It's the job of the envelope to control the flow of heat
between the indoors and outdoors. To maintain our indoor environment,
the envelope must control the flow of heat, air and moisture between
the inside of the home and the outdoors.

http://oee.nrcan.gc.ca/english/index.cfm?attr=4

I got the above from this site. Its about energy efficiency. It has
alot. Take a look. It explains a great deal.

Dean

MathWhiz wrote:
Sure do. How much depends on the temperature differential. If the
basement is only a few degrees cooler, there will be little savings,
but if it is 20 degrees, you will retain more heat and save quite a
bit. .

I'm in New England. At times, it's 50 degrees cooler.

If your basement is 30º F colder, I reject my original answer and
suggest a good amount of insulation.

--
Joseph Meehan

Dia duit

The question is how much, the best would be foam sprayed on of R7 per
inch, second best would be an inch or two of R 7.2" foamboard then
fiberglass batt, the least effective is just fiberglass batt of R 3.5.
Your temp difference is great, foam will also stop air infiltration,
which you dont detect but is happening.

On 1 Sep 2006 03:09:00 -0700, "MathWhiz"
wrote:

We have converted a three season porch into a four season by adding a
gas stove and some new windows. Below is an unfinished basement - the
joists and subfloor are exposed. Do I gain any efficiency by
installing insulation between the joists?

Thanks in advance for any advice.


I hope so, since my house has an unfinished basement, and the whole
first floor has insulation in the floor joists.

The basement gets to low 60's in winter, and floor feels warm. So it
must be working.

later,

tom @ www.WorkAtHomePlans.com

MathWhiz wrote:
We have converted a three season porch into a four season by adding a
gas stove and some new windows. Below is an unfinished basement - the
joists and subfloor are exposed. Do I gain any efficiency by
installing insulation between the joists?

Yes ... but if you ever plan to heat that basement below, it would make
sense to insulate the basement walls now, rather than insulate the
floor, and then the walls later. If not, insulate the floor ... if the
floor feels cold as in, even wall to wall carpet with underpad would
probably provide all the insulation you need. To continue, I had a
similar situation with a hadwood floor ... I insulated the basement
walls.

Sure, but before you do, staple up a loop of some pex tubing between
the joists, and hook it up to a heat exchanger associated with the gas
stove. Warm water circulating under the feet will allow you to stay
comfortable through the winter.

MathWhiz wrote:
We have converted a three season porch into a four season by adding a
gas stove and some new windows. Below is an unfinished basement - the
joists and subfloor are exposed. Do I gain any efficiency by
installing insulation between the joists?

Thanks in advance for any advice.