I've been trying to design my buildings up north so I don't totally
freeze and ran into a lot of aluminum mylar. I'm having trouble
understanding how, what I hear of light speed radiation is going to go
through plywood and reflect back any kind of substantial energy. Or
through concrete. Can anyone explain how radiant barriers are
effective on buildings or maybe suggest another group to ask? Or
should I just keep it for solar experiments?

I'm also lost on how I can design a system to feed the wood stove,
without opening a window to -20 degrees. I'm thinking of having a vent
to the attic to draw from.

Sunworshipper wrote: (clip) Can anyone explain how radiant barriers are
effective on buildings or maybe suggest another group to ask? (clip)
^^^^^^^^^^^^^^^^^
There is radiation of energy from ANY surface, proportional to the 4th power
of the absolute temperature. The transfer between two surfaces is going to
be proportional to the DIFFERENCE in the 4th powers, affected also by other
parameters, INCLUDING the emissivity of the surfaces. Shiny aluminum has a
low emissivity, so it cuts down the radiant transfer. This has nothing to
do with the fact that the outside of the building is being heated by
sunlight. That sun's energy is converted to thermal energy in the plywood,
concrete or whatever else the walls are made of(raises their temperature) ,
and it travels into the wall by conduction. The inner surfaces of the wall
get warmer as a result, which then transmit some of the energy to other
inner surfaces by radiation. Introducing a reflective radiation shield
within an air space sends most of the radiation back the way it came, thus
reducing the heating inside the room.

So aluminum foil can work in two ways: 1.) If it is adhered to a surface,
it lowers the emissivity. If it is suspended in an air gap, it reflects
energy back toward the source.

On Sun, 24 Aug 2008 18:10:03 -0500, Sunworshipper Sunworshipper
wrote:

I've been trying to design my buildings up north so I don't totally
freeze and ran into a lot of aluminum mylar. I'm having trouble
understanding how, what I hear of light speed radiation is going to go
through plywood and reflect back any kind of substantial energy. Or
through concrete. Can anyone explain how radiant barriers are
effective on buildings or maybe suggest another group to ask? Or
should I just keep it for solar experiments?

I'm also lost on how I can design a system to feed the wood stove,
without opening a window to -20 degrees. I'm thinking of having a vent
to the attic to draw from.

it is a property of aluminium that it reflects 97% of incident
infrared radiation. aluminium sheet make a great infrared reflector.

one of the best insulators is polystyrene foam.

On Aug 24, 4:10 pm, Sunworshipper Sunworshipper wrote:
I've been trying to design my buildings up north so I don't totally
freeze and ran into a lot of aluminum mylar. I'm having trouble
understanding how, what I hear of light speed radiation is going to go
through plywood and reflect back any kind of substantial energy. Or
through concrete. Can anyone explain how radiant barriers are
effective on buildings or maybe suggest another group to ask? Or
should I just keep it for solar experiments?

I'm also lost on how I can design a system to feed the wood stove,
without opening a window to -20 degrees. I'm thinking of having a vent
to the attic to draw from.

The effectiveness of radiant barriers greatly depends on the direction
of the heat flow. They work well for heat flow down, but not very
well for heat flow sideways and not well for heat flow up.

Some wood stoves have a way to use outside air for combustion. Most
houses are not sealed so well that one has to open a window when
using them.

Dan

On Aug 24, 7:10 pm, Sunworshipper Sunworshipper wrote:
I've been trying to design my buildings up north so I don't totally
freeze and ran into a lot of aluminum mylar. I'm having trouble
understanding how, what I hear of light speed radiation is going to go
through plywood and reflect back any kind of substantial energy. Or
through concrete. Can anyone explain how radiant barriers are
effective on buildings or maybe suggest another group to ask? Or
should I just keep it for solar experiments?

I'm also lost on how I can design a system to feed the wood stove,
without opening a window to -20 degrees. I'm thinking of having a vent
to the attic to draw from.

Put your hand under or beside (not over) a bright incandescent bulb.
You can feel the heat. Now place a piece of aluminum foil over your
hand. Aluminum is a very good heat conductor so if it heated up you'd
notice fast, but it doesn't. It reflects the infrared heat radiation.

It's a little more difficult to show that emissivity works both ways,
that surfaces which don't absorb heat also don't radiate it. If you
heat black iron or a stove element you can feel the heat radiating off
it with the back of your hand. I just tried and can detect an iron
frypan at 120 F from a few inches away. Do the same with polished
stainless steel or glass and you can't feel it. In fact once the red
glow fades freshly blown lab glassware is a serious burn hazard for a
long time. Since it doesn't radiate it stays hot much longer than you
expect and doesn't warn your hand.

My wood stove is in the basement and the air to feed it comes in
through normal building leaks, especially around the garage door.
Upstairs is better sealed to keep the warm air in. It's like a hot air
balloon which doesn't leak out the top even though the bottom is wide
open.

Some of the cold air feeds the stove and some of it is warmed and
replaces indoor air. I controlled it by watching the humidity while
weatherstripping the upstairs. When it rose to a comfortable level in
winter I stopped tightening the house. I've never measured the air
change or infiltration rate but cooking smells disappear in a few
hours. The heat loss rate is 2~3% of the difference between indoors
and out per hour. You have to find your own acceptable balance between
ventilation and heat loss, those are simple indicators. Thank you
Jimmy Carter for paying for it.

You can easily check draft and airflow by lighting a wadded sheet of
newspaper in the top of the stove, assuming you don't have a catalytic
converter or a badly creosoted, combustible chimney. For mine only a
whisp of smoke will leak out before the chimney begins to draw. That's
a good way to light a fire cleanly, too. If you open a vent into the
attic you may have smoke-flavored cold air rushing down the chimney
when the fire dies out.

Because the living space doesn't leak much air the temperature
difference between floors and rooms is lower than my neighbors'
similar but less well sealed houses. They have to run their stoves
hotter to keep upstairs comfortable. The disadvantage of a stove in
the basement is that the upstairs warms up very slowly, but it does
keep ashes and firewood debris off the rug. Also my wood stove
accessories include a rusty old anvil on a stump that doesn't match
the living room decor.

In summer I vent the bathroom outdoors after a shower and do steamy
cooking outside. I watch the humidity and open windows on nice
evenings. The window seals are wood frames double-glazed with
polyester film and with a few of them out in summer the house breathes
normally.

I live in southern NH which is humid and reaches 100F and with those
few precautions a single window A/C is enough to keep the house
reasonably comfortable and protect the machine tools from rust. Your
results and especially your temperature tolerance may vary.

Jim Wilkins

On Mon, 25 Aug 2008 18:36:27 +0800, Stealth Pilot wrote:
On Sun, 24 Aug 2008 18:10:03 -0500, Sunworshipper wrote:

I've been trying to design my buildings up north so I don't totally
freeze and ran into a lot of aluminum mylar. I'm having trouble
understanding how, what I hear of light speed radiation is going to go
through plywood and reflect back any kind of substantial energy. Or
through concrete. Can anyone explain how radiant barriers are
effective on buildings or maybe suggest another group to ask? Or
should I just keep it for solar experiments?

I'm also lost on how I can design a system to feed the wood stove,
without opening a window to -20 degrees. I'm thinking of having a vent
to the attic to draw from.

it is a property of aluminium that it reflects 97% of incident
infrared radiation. aluminium sheet make a great infrared reflector.

But for total comfort you need the radiant barrier AND depth
insulation (like fiberglass batts) working together.

one of the best insulators is polystyrene foam.

Which is great, except it's seriously flammable - solid gasoline.
Sheet foam insulation must be sealed in the wall or ceiling joists
behind gypsum drywall for practical use, and NOT behind big radiant
heat sources like wood stoves and kilns...

-- Bruce --

On Sun, 24 Aug 2008 18:10:03 -0500, Sunworshipper Sunworshipper
wrote:

Thanks guys, I guess I'll put it in the walls or at least the ceiling.
Just can't see how it will be worth it under the slab. Oh, I didn't
mention the hydronic heating in the slab, though. Got me, playing
ditch digging and rough plumbing at the moment.

On Sun, 31 Aug 2008 14:10:27 -0500, Sunworshipper Sunworshipper
wrote:

On Sun, 24 Aug 2008 18:10:03 -0500, Sunworshipper Sunworshipper
wrote:

Thanks guys, I guess I'll put it in the walls or at least the ceiling.
Just can't see how it will be worth it under the slab. Oh, I didn't
mention the hydronic heating in the slab, though. Got me, playing
ditch digging and rough plumbing at the moment.

Make an accurate map of where each loop goes, and bring up BOTH ENDS
of each loop at the manifold location, and have a shutoff valve for
each return line too. If you manifold the returns without valves and
you get a leak...

And keep the lines deep so you don't accidentally hit a line when
you nail down the interior wall sole plates, or the kitchen island.
Or when bolting down a machine to the slab out in the garage.
Sacrifice a bit of efficiency for longer service life.

Oh! While you are at the Slab stage, remember Floor Drains and
depressed floors in all rooms with water in them - and trap primers if
they won't get refilled with mop water. So when the dishwasher or
icemaker line pops you don't come home to find Noah loading animals
into the Ark...

I screwed up and didn't ride herd on our tile setter - rather than
tiling the washing machine and dryer in a planned-for depressed 'sink'
area of the slab with a bullnose lip at the front edge so the water
would go right into the floor drain there, he raised the drain ring,
filled in the depression and made the floor dead level the whole room.

"But if I put a depression there you can't slide the Washer in and
out...!" Dumb****, You Don't WANT the washer to slide out easily! It
will walk if it gets an unbalanced spin load - Murphy's Law says the
water hoses always pop before the damned thing will unplug itself.

Could have killed him - SHOULD have killed him. Guilty of "Can't
Follow the Clearly Marked By The Architect BLUEPRINTS!!" No court in
Texas would convict... Unfortunately I'm in Californication. I have
to glue down a strip of vinyl cord duct for a flood dam & chock there.

Oh, and if you don't want a floor drain in the bathroom, consider a
floor urinal. It's a floor drain, too - but SWMBO won't allow one in
any other bathroom than the one for the Garage/Shop. They can't stand
it that we get in and out fast...

-- Bruce --

On Sun, 31 Aug 2008 18:18:39 -0700, Bruce L. Bergman
wrote:

On Sun, 31 Aug 2008 14:10:27 -0500, Sunworshipper Sunworshipper
wrote:

On Sun, 24 Aug 2008 18:10:03 -0500, Sunworshipper Sunworshipper
wrote:

Thanks guys, I guess I'll put it in the walls or at least the ceiling.
Just can't see how it will be worth it under the slab. Oh, I didn't
mention the hydronic heating in the slab, though. Got me, playing
ditch digging and rough plumbing at the moment.

Make an accurate map of where each loop goes, and bring up BOTH ENDS
of each loop at the manifold location, and have a shutoff valve for
each return line too. If you manifold the returns without valves and
you get a leak...


I appreciate the help. Reminds me, I need to read up on the oxygen
barrier that I ran into from a thread at ahhh practical machinist from
surfing. I guess their talking about buying the aluminum lined hose...
I was looking for examples of laying out the hoses in concentric
circles instead of zones. Sure, having the option of having curtain
rooms different temperatures would be neat, but I think it would be
better for the slab if it is all kept at the same temp. Plus, the
inner 'zones' may never have to be turned on with all this sandy well
draining gravel knob. I also need to ask my EE friend about cheap
electronic temp. sending units that I'd like to put all over the place
for fun and practical use down the road.


And keep the lines deep so you don't accidentally hit a line when
you nail down the interior wall sole plates, or the kitchen island.
Or when bolting down a machine to the slab out in the garage.
Sacrifice a bit of efficiency for longer service life.

Oh! While you are at the Slab stage, remember Floor Drains and
depressed floors in all rooms with water in them - and trap primers if
they won't get refilled with mop water. So when the dishwasher or
icemaker line pops you don't come home to find Noah loading animals
into the Ark...

I screwed up and didn't ride herd on our tile setter - rather than
tiling the washing machine and dryer in a planned-for depressed 'sink'
area of the slab with a bullnose lip at the front edge so the water
would go right into the floor drain there, he raised the drain ring,
filled in the depression and made the floor dead level the whole room.


Hadn't thought of that, thanks. Maybe cause the washer and dryer where
outside before.


"But if I put a depression there you can't slide the Washer in and
out...!" Dumb****, You Don't WANT the washer to slide out easily! It
will walk if it gets an unbalanced spin load - Murphy's Law says the
water hoses always pop before the damned thing will unplug itself.

Could have killed him - SHOULD have killed him. Guilty of "Can't
Follow the Clearly Marked By The Architect BLUEPRINTS!!" No court in
Texas would convict... Unfortunately I'm in Californication. I have
to glue down a strip of vinyl cord duct for a flood dam & chock there.


I don't know... Did time for the Just Us system and saw all kinds of
suits that I can't talk about.


Oh, and if you don't want a floor drain in the bathroom, consider a
floor urinal. It's a floor drain, too - but SWMBO won't allow one in
any other bathroom than the one for the Garage/Shop. They can't stand
it that we get in and out fast...

-- Bruce --

Is that why!

I'm having real problems with laying out the bathrooms and such at the
moment. Tried to get some more parts today and they are all out of 2"
PVC and then a master plumber attacked me and was saying to use 3" for
the drain pipes, not 4". So need to check this state laws and may
have to switch. Plus they didn't have any rose bud torches for bending
pipe. Might have to try heating the inside of thin walled pipe with a
small torch up at an angle to see if that works. Really need to get
all the pull lines done before the other real plumbing cause they are
much deeper.