Insulating below a floor
 

I've mentioned in other posts about our 135 yr old house we're working on.
At this point I'm rebuilding the floor on the lower level. This house
basically sits on the ground. My new joists will be about 4" off the dirt.
I've been through the "to vent or not to vent" threads about crawl spaces.
I've decided not to ventilate. It's been closed for 135 years, it can keep
being closed. My question is, IS there any reason why I shouldn't fill this
space will insulation? Whether it be fiberglass or blown cellulose? In a
few days I'll have all new joists and proper center support and will
probably insulate unless there's some reason I shouldn't.

thanks!

--
Steve Barker

Insulating below a floor
 

In article , "Steve Barker LT" wrote:
I've mentioned in other posts about our 135 yr old house we're working on.
At this point I'm rebuilding the floor on the lower level. This house
basically sits on the ground. My new joists will be about 4" off the dirt.
I've been through the "to vent or not to vent" threads about crawl spaces.
I've decided not to ventilate. It's been closed for 135 years, it can keep
being closed. My question is, IS there any reason why I shouldn't fill this
space will insulation? Whether it be fiberglass or blown cellulose? In a
few days I'll have all new joists and proper center support and will
probably insulate unless there's some reason I shouldn't.

I don't see how that insulation will do much insulating. A shallow
unvented crawl space makes for a reasonable insulator by itself.
However, it could provide a bridge/path for moisture or bugs to cross
from the dirt to the joists and floor. It might also make subsequent
jobs a little harder (e.g. pulling some new power or CAT-5 cable).

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

Insulating below a floor
 

Malcolm Hoar wrote:
In article , "Steve Barker LT" wrote:
being closed. My question is, IS there any reason why I shouldn't fill this
space will insulation?

I don't see how that insulation will do much insulating.

I concur with Malcolm. I'd just insulate the perimeter walls, making
very sure to use appropriate flashing or whatever to make a barrier
between the ground and the insulation (which would otherwise provide a
termite/bug/stuff path). Maybe you also want to put down a sturdy vapor
barrier over the entire dirt floor, if you haven't already.

Other than that, the air itself will provide decent insulation.

-kevin

Insulating below a floor
 

"kevin" wrote in message

Other than that, the air itself will provide decent insulation.

-kevin

If that is true, why don't they just leave the air space between the
sheathing and drywall in a house? Why do we waste money putting up all the
fiberglass?

I'd insulate with two inches of foam board at a minimum.

Insulating below a floor
 

Been there done that, pointless waste of time and materials. The floors
were nearly, if not, as cold after the install. We did a good job &
hung R-19 between the joists with chicken wire to hold it in place.
Warm air rises, cold air sinks you aren't really changing anything.

Insulating below a floor
 

Now any moisture passes up through the house that comes up from the
ground, who knows how much water the insulation might hold possibly
leading to rot. 1st put down a plastic moisture barrier on the dirt.
Your location, amount of rain and soil humidity need to be known first.
If its to high you will have problems.

Insulating below a floor
 

"Eric in North TX" wrote in message
oups.com...

Been there done that, pointless waste of time and materials. The floors
were nearly, if not, as cold after the install. We did a good job &
hung R-19 between the joists with chicken wire to hold it in place.
Warm air rises, cold air sinks you aren't really changing anything.


You certainly are changing things. Heat moves three ways, conduction,
convection, radiation. You are addressing only convection. While hot air
is rising, heat can also be conducted to the ground that is a lower
temperature. Heat always moves to where there is less of it. Laws of
physics, not opinion.

Were the floors as cold after you insulated? Any flat smooth surface is
going to feel cool at room temperature. It has to do with skin contact to
the smooth surface. Your body is about 97 degrees. The floor is about 70
degrees. Following the laws of physics, the heat from your body is drawn to
the cooker surface. A flat wood, tile, or concrete floor is going to feel
cooler than a carpeted one because of the greater surface contact as
compared to a bumpy one with air pockets.

Putting insulation under the floor reduces the amount of heat that can pass
as it is drawn to the cooler area.

Insulating below a floor
 

All I know is that any other improvement to insulation, (better doors,
better windows, walls stuffed, attic R level raised) have shown a
marked and noticeable difference both in utilities and comfort. The
floor joist job was a 1 on a scale of 1-10 with 1 sucking and 10 as
fantastic, if I had it to do over, I'd just have thrown the same amount
of insulation into the attic.

Insulating below a floor
 

In article , "Edwin Pawlowski" wrote:

"Eric in North TX" wrote in message
roups.com...

Been there done that, pointless waste of time and materials. The floors
were nearly, if not, as cold after the install. We did a good job &
hung R-19 between the joists with chicken wire to hold it in place.
Warm air rises, cold air sinks you aren't really changing anything.


You certainly are changing things. Heat moves three ways, conduction,
convection, radiation. You are addressing only convection. While hot air
is rising, heat can also be conducted to the ground that is a lower
temperature. Heat always moves to where there is less of it. Laws of
physics, not opinion.

Were the floors as cold after you insulated? Any flat smooth surface is
going to feel cool at room temperature. It has to do with skin contact to
the smooth surface. Your body is about 97 degrees. The floor is about 70
degrees. Following the laws of physics, the heat from your body is drawn to
the cooker surface. A flat wood, tile, or concrete floor is going to feel
cooler than a carpeted one because of the greater surface contact as
compared to a bumpy one with air pockets.

Bingo! Air pockets.

Still air is an excellent insulator. Most insulation materials
are largely comprised of ummmm, air.

Putting insulation under the floor reduces the amount of heat that can pass
as it is drawn to the cooler area.

The OP already has some of that under the floor. His crawl space
is sealed (not vented) and shallow. Additional insulation will
help in theory but the effect will be insignificant in practice,
in my view.

If his crawl space was 3 foot deep and ventilated, that would
be a very different situation.

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

Insulating below a floor
 

put your zipcode in the manufacturer's blank at:
http://www.owenscorning.com/around/r...?ckie=complete

and read up at:
http://www.buildingscience.com/resources/homeowner.htm


Steve Barker LT wrote:
I've mentioned in other posts about our 135 yr old house we're working on.
At this point I'm rebuilding the floor on the lower level. This house
basically sits on the ground. My new joists will be about 4" off the dirt.
I've been through the "to vent or not to vent" threads about crawl spaces.
I've decided not to ventilate. It's been closed for 135 years, it can keep
being closed. My question is, IS there any reason why I shouldn't fill this
space will insulation? Whether it be fiberglass or blown cellulose? In a
few days I'll have all new joists and proper center support and will
probably insulate unless there's some reason I shouldn't.

thanks!

--
Steve Barker

Insulating below a floor
 

Eric in North TX wrote:

Warm air rises, cold air sinks...

But air conducts and heat radiates downwards. A vapor barrier on
the ground to avoid moisture and a layer of foil over the joists
with air gaps above and below can save energy.

Nick

Insulating below a floor
 

Edwin Pawlowski wrote:

... Your body is about 97 degrees. The floor is about 70 degrees.
Following the laws of physics, the heat from your body is drawn to
the cooker surface.

Then again, we have shoes, and a small foot surface.

Nick

Insulating below a floor
 

In article , wrote:
Eric in North TX wrote:

Warm air rises, cold air sinks...

But air conducts

...less than almost anything other than a vacuum. Check
the thermal conductivity of air in a suitable reference
work.

and heat radiates downwards.

And a floor, which is generally not very warm to start
with, isn't going to radiate very much (in any direction).

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

Insulating below a floor
 

IF my crawl space was 3', I'd be in hog heaven!! LOL! It's amazing the
planning you have to do with plumbing and electrical if you don't want, (or
can't get) ANY of it below the floor.


Steve


PS. THANKS for all the replies. I think I'll plastic the dirt, and perhaps
foam board around the perimeter and be done. I'll post pictures someday.
G

s


"Malcolm Hoar" wrote in message
...
In article , "Edwin
Pawlowski" wrote:

"Eric in North TX" wrote in message
groups.com...

Been there done that, pointless waste of time and materials. The floors
were nearly, if not, as cold after the install. We did a good job &
hung R-19 between the joists with chicken wire to hold it in place.
Warm air rises, cold air sinks you aren't really changing anything.


You certainly are changing things. Heat moves three ways, conduction,
convection, radiation. You are addressing only convection. While hot air
is rising, heat can also be conducted to the ground that is a lower
temperature. Heat always moves to where there is less of it. Laws of
physics, not opinion.

Were the floors as cold after you insulated? Any flat smooth surface is
going to feel cool at room temperature. It has to do with skin contact to
the smooth surface. Your body is about 97 degrees. The floor is about 70
degrees. Following the laws of physics, the heat from your body is drawn
to
the cooker surface. A flat wood, tile, or concrete floor is going to feel
cooler than a carpeted one because of the greater surface contact as
compared to a bumpy one with air pockets.

Bingo! Air pockets.

Still air is an excellent insulator. Most insulation materials
are largely comprised of ummmm, air.

Putting insulation under the floor reduces the amount of heat that can
pass
as it is drawn to the cooler area.

The OP already has some of that under the floor. His crawl space
is sealed (not vented) and shallow. Additional insulation will
help in theory but the effect will be insignificant in practice,
in my view.

If his crawl space was 3 foot deep and ventilated, that would
be a very different situation.

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

Insulating below a floor
 

thanks for the links. I need all the mold info i can get.

steve


"buffalobill" wrote in message
oups.com...
put your zipcode in the manufacturer's blank at:
http://www.owenscorning.com/around/r...?ckie=complete

and read up at:
http://www.buildingscience.com/resources/homeowner.htm


Steve Barker LT wrote:
I've mentioned in other posts about our 135 yr old house we're working
on.
At this point I'm rebuilding the floor on the lower level. This house
basically sits on the ground. My new joists will be about 4" off the
dirt.
I've been through the "to vent or not to vent" threads about crawl
spaces.
I've decided not to ventilate. It's been closed for 135 years, it can
keep
being closed. My question is, IS there any reason why I shouldn't fill
this
space will insulation? Whether it be fiberglass or blown cellulose? In
a
few days I'll have all new joists and proper center support and will
probably insulate unless there's some reason I shouldn't.

thanks!

--
Steve Barker

Insulating below a floor
 

Steve Barker LT wrote:

I've mentioned in other posts about our 135 yr old house we're working on.
At this point I'm rebuilding the floor on the lower level. This house
basically sits on the ground. My new joists will be about 4" off the dirt.
I've been through the "to vent or not to vent" threads about crawl spaces.
I've decided not to ventilate. It's been closed for 135 years, it can keep
being closed. My question is, IS there any reason why I shouldn't fill this
space will insulation? Whether it be fiberglass or blown cellulose? In a
few days I'll have all new joists and proper center support and will
probably insulate unless there's some reason I shouldn't.

thanks!

Hi,
When I converted my backyard deck(lean to house) into a 4 season sun
room, I replaced decking with a ready made floor panel sections
sandwiched with R-30 foam core. This was installed on top of joists.
Then directly Armstrong vinyl flooring roll was put down.
I believe this foam core comes in various thickness for your needs.

Insulating below a floor
 

In article , "Edwin Pawlowski" wrote:

"kevin" wrote in message

Other than that, the air itself will provide decent insulation.

-kevin

If that is true, why don't they just leave the air space between the
sheathing and drywall in a house? Why do we waste money putting up all the
fiberglass?

1. There's typically a lot more outside wall than there is
floor (in terms of square feet). More heat loss.

2. Because warm air rises and the walls are therefore
normally a lot warmer than the floor. More heat loss.

3. And most of all, because the outside walls are subject
to the wind chill effect. More heat loss. The floor is
insulated by the dirt and rock -- quite a few feet of
it too ;-)

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

Insulating below a floor
 

"Malcolm Hoar" wrote in message

3. And most of all, because the outside walls are subject
to the wind chill effect. More heat loss. The floor is
insulated by the dirt and rock -- quite a few feet of
it too ;-)

But the earth is cooler than the inside air. As long as it is cooler, is not
Insulated, it is drawing heat. Insulation helps. Energy efficient homes are
built with 1" or 2" of insulation under the slab.

I agree that other places have much more heat loss, but over time, loss is
loss and if you can stop it you save money. Don't just take my word for it.

http://www.hgtvpro.com/hpro/bp_insul...463250,00.html

http://www.buildingscience.com/resou...r_basement.pdf

https://www03.cmhc-schl.gc.ca/b2c/b2...00420000000051

Insulating below a floor
 

In article , "Edwin Pawlowski" wrote:

"Malcolm Hoar" wrote in message

3. And most of all, because the outside walls are subject
to the wind chill effect. More heat loss. The floor is
insulated by the dirt and rock -- quite a few feet of
it too ;-)

But the earth is cooler than the inside air. As long as it is cooler, is not
Insulated, it is drawing heat. Insulation helps.

Sure, more is always better. Insulatio ad absurdum.

Energy efficient homes are built with 1" or 2" of insulation under the slab.

But the OP doesn't have a slab.

Besides, what is 1" or 2" of insulation under a slab? It's
effectively 1" or 2" of air.

The OP already has that and more.

I agree that other places have much more heat loss, but over time, loss is
loss and if you can stop it you save money.

It generally costs money to insulate and some of those
investments can pay for themselves very quickly. Others
never recoup the initial cost.

And if inappropriately installed insulation creates or
contributes to moisture problems, rot and mold one has
a highly negative return.

Don't just take my word for it.

http://www.hgtvpro.com/hpro/bp_insul...150_3463250,00.
html

http://www.buildingscience.com/resou...our_basement.p
df

https://www03.cmhc-schl.gc.ca/b2c/b2...1EN&areaID=000
0000042&productID=00000000420000000051

Since the OP doesn't have a basement or a slab I'm not
sure what point these links are trying to make.


--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

Insulating below a floor
 

Malcolm Hoar wrote:
In article , "Edwin Pawlowski" wrote:

"Malcolm Hoar" wrote in message

3. And most of all, because the outside walls are subject
to the wind chill effect. More heat loss. The floor is
insulated by the dirt and rock -- quite a few feet of
it too ;-)

But the earth is cooler than the inside air. As long as it is cooler, is not
Insulated, it is drawing heat. Insulation helps.


Sure, more is always better. Insulatio ad absurdum.


Energy efficient homes are built with 1" or 2" of insulation under the slab.


But the OP doesn't have a slab.

Besides, what is 1" or 2" of insulation under a slab? It's
effectively 1" or 2" of air.

The OP already has that and more.


I agree that other places have much more heat loss, but over time, loss is
loss and if you can stop it you save money.


It generally costs money to insulate and some of those
investments can pay for themselves very quickly. Others
never recoup the initial cost.

And if inappropriately installed insulation creates or
contributes to moisture problems, rot and mold one has
a highly negative return.


Don't just take my word for it.

http://www.hgtvpro.com/hpro/bp_insul...150_3463250,00.
html

http://www.buildingscience.com/resou...our_basement.p
df

https://www03.cmhc-schl.gc.ca/b2c/b2...1EN&areaID=000
0000042&productID=00000000420000000051


Since the OP doesn't have a basement or a slab I'm not
sure what point these links are trying to make.


Don't listen to these people, insulate.

As far as venting etc, you are chinging things from what they were over
the last 150 years, so things will change....

If you are worried about moisture etc, use foam.

Insulating below a floor
 

In article ,
Malcolm Hoar wrote:
In article , wrote:
Eric in North TX wrote:

Warm air rises, cold air sinks...

But air conducts

..less than almost anything other than a vacuum. Check
the thermal conductivity of air in a suitable reference
work.

and heat radiates downwards.

And a floor, which is generally not very warm to start
with, isn't going to radiate very much (in any direction).

Indeed!

I recall from eons ago class that the radiation amount
varies as the (absolute!) temperature TO THE FOURTH POWER.

David