My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven. Things inside (like
projects) get warm to the touch and the ambient temperature soars to
about 105°(40.6°C). I've had to move all glues and solvents and
anything else that might be temperature sensitive into the house. As
you can imagine, it makes things like brushing shellac difficult. Any
ideas for a cheap remedy just for the radiating heat problem? I know I
could insulate the roof, but that isn't the direction I want to go with
this space. Before winter sets in, I want to frame about half of the
inside of the building into a room for the wood shop and insulate that,
but I didn't want to do it now. The building is about a 1000 sq/ft and
the roof is over 12' high at the peak, so that isn't very practical
anyway. I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

In a word, NO! Been there, done that. I had a shed that was hotter
than a firecracker when the sun came out. I painted the roof stark
white and put a thin layer of insulation on the inside of the roof. The
temperature drop was nearly unnoticeable. Years later I tore the shed
down and built my own. fiberglass shingle roof, 2 small gable vents,
thicker insulation AND I insulated the walls that were exposed to the
sun. Now on a HOT, HOT day I can walk into that shed and be greeted by
coolness akin to walking under a large shade tree.

If you don't insulate where the heat load is coming from you can forget
about cooling your shop. Of course the dark roof is much of the
problem, but the larger problem is lack of insulation.

Dave



Hax Planx wrote:
My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven. Things inside (like
projects) get warm to the touch and the ambient temperature soars to
about 105°(40.6°C). I've had to move all glues and solvents and
anything else that might be temperature sensitive into the house. As
you can imagine, it makes things like brushing shellac difficult. Any
ideas for a cheap remedy just for the radiating heat problem? I know I
could insulate the roof, but that isn't the direction I want to go with
this space. Before winter sets in, I want to frame about half of the
inside of the building into a room for the wood shop and insulate that,
but I didn't want to do it now. The building is about a 1000 sq/ft and
the roof is over 12' high at the peak, so that isn't very practical
anyway. I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

"Hax Planx" wrote in message
.net...

Snip
I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

Well I am going to differ from David's view. I live in Houston. Last
year I built a storage room in my back yard with no insulation. I used
Radiant barrier decking for the roof and went with 30# felt and a premium
asphalt shingle on top of that.
The room stays closed up all day long and the inside temperature never feels
higher than the out side temperature. 2 weeks ago I painted the out side a
medium brown color and the inside temperature rose slightly.
While it may not be feasible to re roof your building and put down radiant
barrier decking there is radiant barrier paint that can be sprayed up on the
bottom of the roof. They may help and be relatively inexpensive.
Keep in mind also that insulation does not warm or cool a building it simply
slows the temperature movement going from a warmer area to a cooler area.
If the building does not cool down at night insulation is probably not going
to help. IMHO the trick here is to reflect the heat with the proper
materials.

Oddly the radiant barrier products face towards the inside of the building.
the metallic surface on the decking faced down and the radiant barrier paint
is applied on the same surface facing down.

is that room primarily or wholly in the shade, Leon? There isn't any
way to be comfortable in a totally uninsulated outbuilding here during
the summer if the sun beats down on it. White roof, brown roof, purple
roof--makes such a marginal difference if there's no insulation in the
walls/roof. In fact I've got almost the same roof on my shed as on my
house and the house is hotter than the shed because of all the frickin
single pane glass that I've yet to replace. Removing a wide sliding
door (single pane) on the south side of the house and replacing it with
a 36" triple glazed door helped tremendously to keep that end of the
house cooler. YMMV--and apparently it does. g

Dave

Leon wrote:
"Hax Planx" wrote in message
.net...

Snip
I was thinking along the lines of maybe using a reflective

coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?


Well I am going to differ from David's view. I live in Houston. Last
year I built a storage room in my back yard with no insulation. I used
Radiant barrier decking for the roof and went with 30# felt and a premium
asphalt shingle on top of that.
The room stays closed up all day long and the inside temperature never feels
higher than the out side temperature. 2 weeks ago I painted the out side a
medium brown color and the inside temperature rose slightly.
While it may not be feasible to re roof your building and put down radiant
barrier decking there is radiant barrier paint that can be sprayed up on the
bottom of the roof. They may help and be relatively inexpensive.
Keep in mind also that insulation does not warm or cool a building it simply
slows the temperature movement going from a warmer area to a cooler area.
If the building does not cool down at night insulation is probably not going
to help. IMHO the trick here is to reflect the heat with the proper
materials.

Oddly the radiant barrier products face towards the inside of the building.
the metallic surface on the decking faced down and the radiant barrier paint
is applied on the same surface facing down.

"David" wrote in message
...
is that room primarily or wholly in the shade, Leon? There isn't any way
to be comfortable in a totally uninsulated outbuilding here during the
summer if the sun beats down on it. White roof, brown roof, purple
roof--makes such a marginal difference if there's no insulation in the
walls/roof. In fact I've got almost the same roof on my shed as on my
house and the house is hotter than the shed because of all the frickin
single pane glass that I've yet to replace. Removing a wide sliding door
(single pane) on the south side of the house and replacing it with a 36"
triple glazed door helped tremendously to keep that end of the house
cooler. YMMV--and apparently it does. g


No, not in the shade at all. In fact when I painted it brown it became
slightly warmer. I went with radiant barrier because I wanted to see if it
really worked and it only cost me $24 more than standard decking. I was
really amazed at how much it helped.

"Leon" wrote in message ...

"David" wrote in message

No, not in the shade at all. In fact when I painted it brown it became
slightly warmer. I went with radiant barrier because I wanted to see if
it
really worked and it only cost me $24 more than standard decking. I was
really amazed at how much it helped.

It _is_ amazing how proper construction methods can keep temperatures down
inside a structure.

I just walked in from checking the gas furnace line installation in the
attic of a new house built with radiant barrier roof decking and ridge
venting ... it was no hotter in that attic than it is outside today in
Houston.

As you well appreciate, being in an attic in Houston at 11 AM on a sunny
June day can be a scorching experience in the older houses. AAMOF, the
shingles on this one were already too hot to install the HVAC roof vents ...
I like to have that done at first light, before the sun get overhead, to
keep from damaging the shingles.

Now, if I ever get the time to build that new $hop ...

--
www.e-woodshop.net
Last update: 5/14/05

On Tue, 28 Jun 2005 10:21:13 -0500, Hax Planx
wrote:

My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven. Things inside (like
projects) get warm to the touch and the ambient temperature soars to
about 105°(40.6°C). I've had to move all glues and solvents and
anything else that might be temperature sensitive into the house. As
you can imagine, it makes things like brushing shellac difficult. Any
ideas for a cheap remedy just for the radiating heat problem? I know I
could insulate the roof, but that isn't the direction I want to go with
this space. Before winter sets in, I want to frame about half of the
inside of the building into a room for the wood shop and insulate that,
but I didn't want to do it now. The building is about a 1000 sq/ft and
the roof is over 12' high at the peak, so that isn't very practical
anyway. I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

here in n.c. it gets pretty hot in the summer months. do you have
vents at each end of the building? if so, you could put a large fan
blowing out at one end. my shop is uninsulated also exept for the foam
sheating under the siding. nothing in the roof. it is under a few
shade trees and 2 story so i am sure that is helping. my shop stayes
cool up till around 4 pm in the summer. after then i go to the house.
if you dont insulate then ventilation and air flow are the key to
keeping cool. on days i want to work in the late afternoon i set a fan
blowing in downstairs and one or two blowing out upstairs. seems to
work ok. i have a window a c unit that suposedly works. havent ever
pluged it in so i cant say weather it does or not. you are welcome to
it if ya want to haul it home. maybe it willl make it cooler to work
in there but might be kind o exspensive. lol.

skeez

Hax Planx wrote:
My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven. Things inside (like
projects) get warm to the touch and the ambient temperature soars to
about 105°(40.6°C). I've had to move all glues and solvents and
anything else that might be temperature sensitive into the house. As
you can imagine, it makes things like brushing shellac difficult. Any
ideas for a cheap remedy just for the radiating heat problem? I know I
could insulate the roof, but that isn't the direction I want to go with
this space. Before winter sets in, I want to frame about half of the
inside of the building into a room for the wood shop and insulate that,
but I didn't want to do it now. The building is about a 1000 sq/ft and
the roof is over 12' high at the peak, so that isn't very practical
anyway. I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

I'd start with a gable mounted vent fan.

--
Jack Novak
Buffalo, NY - USA

(Remove -SPAM- to send email)

How about actively removing the heat: a gable-mounted exhaust fan, with
or without a thermostat control. Depending on the CFM, you'll need a
certain area of "inlet" into your shop of fresh air - got a screened
window?

The collateral benefit to the exhaust fan is it moves out the fine dust
too.

-Chris

Hax Planx wrote:
My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven.

"Swingman" wrote in message
...

It _is_ amazing how proper construction methods can keep temperatures down
inside a structure.

It is amazing. My wife and I have been looking at new homes and Ryland is
guaranteeing that heating and cooling costs will not be over about $50 per
month on average for a full 3 years. This is on homes ranging in size from
2,000 to 3000 sq feet. IIRC they are using radiant barrier plus that new
blown in wall insulation that is made up of old newspapers like on TOH.



I just walked in from checking the gas furnace line installation in the
attic of a new house built with radiant barrier roof decking and ridge
venting ... it was no hotter in that attic than it is outside today in
Houston.

That is the way my store room is. You can almost touch the decking and it
is no warmer.


As you well appreciate, being in an attic in Houston at 11 AM on a sunny
June day can be a scorching experience in the older houses. AAMOF, the
shingles on this one were already too hot to install the HVAC roof vents
...
I like to have that done at first light, before the sun get overhead, to
keep from damaging the shingles.

Now, if I ever get the time to build that new $hop ...

Where are you planing on putting that new shop? LOL

Are we really arguing?? Isn't a radiant barrier a form of insulation?

Dave

Leon wrote:
"David" wrote in message
...

is that room primarily or wholly in the shade, Leon? There isn't any way
to be comfortable in a totally uninsulated outbuilding here during the
summer if the sun beats down on it. White roof, brown roof, purple
roof--makes such a marginal difference if there's no insulation in the
walls/roof. In fact I've got almost the same roof on my shed as on my
house and the house is hotter than the shed because of all the frickin
single pane glass that I've yet to replace. Removing a wide sliding door
(single pane) on the south side of the house and replacing it with a 36"
triple glazed door helped tremendously to keep that end of the house
cooler. YMMV--and apparently it does. g


No, not in the shade at all. In fact when I painted it brown it became
slightly warmer. I went with radiant barrier because I wanted to see if it
really worked and it only cost me $24 more than standard decking. I was
really amazed at how much it helped.

"David" wrote in message
...
Are we really arguing?? Isn't a radiant barrier a form of insulation?

No, not really by definition, although its purpose is pretty much the same.
It reflects the heat rather than stops its movement into a cooler area.
Insulation pretty much absorbs heat.

"Leon" wrote in message
news

"David" wrote in message
...
Are we really arguing?? Isn't a radiant barrier a form of insulation?

No, not really by definition, although its purpose is pretty much the
same. It reflects the heat rather than stops its movement into a cooler
area. Insulation pretty much absorbs heat.


As a P.S. to my comment. My supplier was very insistant that knew to lay
the radiant barrier decking with the foil side down as some of the
installers put it with the foil side up and the roofs only lasted 4 or 5
years. Radiant barrier IIRC does nothing to keep a house from getting cold
in the winter.

What about a swamp cooler?

Spray isocythene insulation would be a solution. Also something like
the foil/bubble/bubble/foil insulation would be easy to install (just
need a staple gun and the time) and I did that a couple years ago on
a addition (quasi-garage) we built with BOTH the
foil/bubble/bubble/file AND fiberglass bats in the wall studs, and it
is noticeably cooler in there than outside util be open up the garage
doors at both ends, then it equilabrates to the outside temp

I totally agree, without adding insulation/radiant barriers, you are
not going to accomplish any significant temp reductions

John

On Tue, 28 Jun 2005 15:58:05 GMT, "Leon"
wrote:


"Hax Planx" wrote in message
t.net...

Snip
I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

Well I am going to differ from David's view. I live in Houston. Last
year I built a storage room in my back yard with no insulation. I used
Radiant barrier decking for the roof and went with 30# felt and a premium
asphalt shingle on top of that.
The room stays closed up all day long and the inside temperature never feels
higher than the out side temperature. 2 weeks ago I painted the out side a
medium brown color and the inside temperature rose slightly.
While it may not be feasible to re roof your building and put down radiant
barrier decking there is radiant barrier paint that can be sprayed up on the
bottom of the roof. They may help and be relatively inexpensive.
Keep in mind also that insulation does not warm or cool a building it simply
slows the temperature movement going from a warmer area to a cooler area.
If the building does not cool down at night insulation is probably not going
to help. IMHO the trick here is to reflect the heat with the proper
materials.

Oddly the radiant barrier products face towards the inside of the building.
the metallic surface on the decking faced down and the radiant barrier paint
is applied on the same surface facing down.

$50 a month for heating and cooling ??? They must have
figured out a brand new way to heat water for the
laundry or dish washer.

At the VERY cheap rate of .08 per kwh, that works out
to 625 kwh per month for heat or cooling.

I don't think my home would be that low if "nobody"
was living there.

I assume these homes are NOT total electric ???





Leon wrote:




It is amazing. My wife and I have been looking at new homes and Ryland is
guaranteeing that heating and cooling costs will not be over about $50 per
month on average for a full 3 years. This is on homes ranging in size from
2,000 to 3000 sq feet. IIRC they are using radiant barrier plus that new
blown in wall insulation that is made up of old newspapers like on TOH.

In article ,
Hax Planx wrote:
My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven. Things inside (like
projects) get warm to the touch and the ambient temperature soars to
about 105°(40.6°C). I've had to move all glues and solvents and
anything else that might be temperature sensitive into the house. As
you can imagine, it makes things like brushing shellac difficult. Any
ideas for a cheap remedy just for the radiating heat problem? I know I
could insulate the roof, but that isn't the direction I want to go with
this space. Before winter sets in, I want to frame about half of the
inside of the building into a room for the wood shop and insulate that,
but I didn't want to do it now. The building is about a 1000 sq/ft and
the roof is over 12' high at the peak, so that isn't very practical
anyway. I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

There are a few 'cheap' solutions.

1) a large 'barn fan'. venting to the outside. this will help pull the
'inside' temperature down to 'approximately' what it is outside.

2) "water the roof". Intermittantly -- just enough to dampen it, and let
it evaporate off. As long as the ambient humidity isn't excessive,
your water costs are reasonable, and you don't have excessive amounts
of minerals in the water, this can be suprisingly effective. If tap
water quality is suspect, or expensive, build a cistern to capture
the rainwater from the roof, and 'recycle' it.

On 28 Jun 2005 13:13:11 -0700, "Dhakala"
wrote:

What about a swamp cooler?


I cobbled a swamp cooler together to use in my garage here in the
Dallas area. Box fan with a mister in front of it, water feed from a 2
gal jug. Not fancy but it helps. As outside humidity rises, it becomes
much less effective, but below 40% relative humidity it drops the temp
about 15 degress if ambient temp outside is 85 degrees F. It does,
obviously, raise the humidity in the garage a bit.

Regards.

Robert Bonomi says...

1) a large 'barn fan'. venting to the outside. this will help pull the
'inside' temperature down to 'approximately' what it is outside.

2) "water the roof". Intermittantly -- just enough to dampen it, and let
it evaporate off. As long as the ambient humidity isn't excessive,
your water costs are reasonable, and you don't have excessive amounts
of minerals in the water, this can be suprisingly effective. If tap
water quality is suspect, or expensive, build a cistern to capture
the rainwater from the roof, and 'recycle' it.

Water is an interesting idea. I'll have to try that.

Dhakala says...

What about a swamp cooler?

For 1000 sq ft?

TheNewGuy says...

How about actively removing the heat: a gable-mounted exhaust fan, with
or without a thermostat control. Depending on the CFM, you'll need a
certain area of "inlet" into your shop of fresh air - got a screened
window?

The collateral benefit to the exhaust fan is it moves out the fine dust
too.

-Chris

A gable fan and vent system would be nice, but it is a cinder block
building and the cinder blocks go all the way to the crown. Would a fan
really cut down much on the radiant heat?

skeezics says...

here in n.c. it gets pretty hot in the summer months. do you have
vents at each end of the building? if so, you could put a large fan
blowing out at one end. my shop is uninsulated also exept for the foam
sheating under the siding. nothing in the roof. it is under a few
shade trees and 2 story so i am sure that is helping. my shop stayes
cool up till around 4 pm in the summer. after then i go to the house.
if you dont insulate then ventilation and air flow are the key to
keeping cool. on days i want to work in the late afternoon i set a fan
blowing in downstairs and one or two blowing out upstairs. seems to
work ok. i have a window a c unit that suposedly works. havent ever
pluged it in so i cant say weather it does or not. you are welcome to
it if ya want to haul it home. maybe it willl make it cooler to work
in there but might be kind o exspensive. lol.

skeez

I can only imagine what I would pay for AC out there. No vents and they
would be difficult to install.

Leon says...

Well I am going to differ from David's view. I live in Houston. Last
year I built a storage room in my back yard with no insulation. I used
Radiant barrier decking for the roof and went with 30# felt and a premium
asphalt shingle on top of that.
The room stays closed up all day long and the inside temperature never feels
higher than the out side temperature. 2 weeks ago I painted the out side a
medium brown color and the inside temperature rose slightly.
While it may not be feasible to re roof your building and put down radiant
barrier decking there is radiant barrier paint that can be sprayed up on the
bottom of the roof. They may help and be relatively inexpensive.
Keep in mind also that insulation does not warm or cool a building it simply
slows the temperature movement going from a warmer area to a cooler area.
If the building does not cool down at night insulation is probably not going
to help. IMHO the trick here is to reflect the heat with the proper
materials.

Oddly the radiant barrier products face towards the inside of the building.
the metallic surface on the decking faced down and the radiant barrier paint
is applied on the same surface facing down.

I'm thinking a radiant barrier would help a lot. Actually, just about
any barrier would probably help. I asked about radiant barrier paint
today at a box store and the paint guru said they had glow in the dark
paint and fluorescent colors. I said nothing and walked away with a
permanent loss of an IQ point. I saw I could get 1000 sq ft of radiant
barrier online for $100 and $40 shipping, but installing it would be an
interesting challenge. That's probably the way to go for the long run
though.

David says...

In a word, NO! Been there, done that. I had a shed that was hotter
than a firecracker when the sun came out. I painted the roof stark
white and put a thin layer of insulation on the inside of the roof. The
temperature drop was nearly unnoticeable. Years later I tore the shed
down and built my own. fiberglass shingle roof, 2 small gable vents,
thicker insulation AND I insulated the walls that were exposed to the
sun. Now on a HOT, HOT day I can walk into that shed and be greeted by
coolness akin to walking under a large shade tree.

If you don't insulate where the heat load is coming from you can forget
about cooling your shop. Of course the dark roof is much of the
problem, but the larger problem is lack of insulation.

Dave

I know renovation is probably the way to go, but I was hoping for a band
aid cure for now.

Does anyone have any actual experience with the radiant barrier paints?
Are they as effective as aluminum barriers assuming both are applied
against the roof decking?

On Tue, 28 Jun 2005 10:21:13 -0500, Hax Planx
wrote:

My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven. Things inside (like
projects) get warm to the touch and the ambient temperature soars to
about 105°(40.6°C).

I think more attic ventilation would probably help.
Use roof vents or a powered fan in the gable end. If you have soffits
add soffit vents and if not put a passive vent in the opposite gable
end. Since it sounds like the building does not have a ceiling you
could get your lower ventilation from leaving windows open.

Mike O.

On Tue, 28 Jun 2005 18:18:34 -0500, Hax Planx
wrote:

skeezics says...

here in n.c. it gets pretty hot in the summer months. do you have
vents at each end of the building? if so, you could put a large fan
blowing out at one end. my shop is uninsulated also exept for the foam
sheating under the siding. nothing in the roof. it is under a few
shade trees and 2 story so i am sure that is helping. my shop stayes
cool up till around 4 pm in the summer. after then i go to the house.
if you dont insulate then ventilation and air flow are the key to
keeping cool. on days i want to work in the late afternoon i set a fan
blowing in downstairs and one or two blowing out upstairs. seems to
work ok. i have a window a c unit that suposedly works. havent ever
pluged it in so i cant say weather it does or not. you are welcome to
it if ya want to haul it home. maybe it willl make it cooler to work
in there but might be kind o exspensive. lol.

skeez

I can only imagine what I would pay for AC out there. No vents and they
would be difficult to install.

its a window unit. missing the inside grill but in a shop it wont
matter. i was going to cut a hole in the wall for it but my shop seems
to stay cool enough.

skeez

I re-roofed my entire house and garage in January. I went back with
radiant barrier and ridge vents AND a BLACK roof! The garage (my shop)
is now cooler than it has ever been. I lower the garage door about
half way in the afternoon to block the afternoon sun. Its the first
time I've been able to tolerate working out there during the day in the
summer. Yes, I need a fan blowing on me, but it used to be unworkable
at all.

As you know, I too, live in Houston.

Bob Davis

Why not a swamp cooler for 1000 sq. ft.? Today, I saw a $350 unit at
Home Depot rated for 800 feet. The $450 unit was rated for 1500 feet.

It's not for your square feet. It's for your comfort, right? :-)

On Tue, 28 Jun 2005 18:11:23 -0500, the opaque Hax Planx
spake:

Robert Bonomi says...

1) a large 'barn fan'. venting to the outside. this will help pull the
'inside' temperature down to 'approximately' what it is outside.

2) "water the roof". Intermittantly -- just enough to dampen it, and let
it evaporate off. As long as the ambient humidity isn't excessive,
your water costs are reasonable, and you don't have excessive amounts
of minerals in the water, this can be suprisingly effective. If tap
water quality is suspect, or expensive, build a cistern to capture
the rainwater from the roof, and 'recycle' it.

Water is an interesting idea. I'll have to try that.

Put a small sprinkler up there and plumb it indoors so you can turn
it on and off at will.

- This product cruelly tested on defenseless furry animals -
--------------------------------------------------------
http://diversify.com Web App & Database Programming

"Pat Barber" wrote in message
...
$50 a month for heating and cooling ??? They must have
figured out a brand new way to heat water for the
laundry or dish washer.

I don't think my home would be that low if "nobody" was living there.


Laundry and dishwashing are not heating and cooling costs directly.

The $50 sounds very cheap given today's energy, but not impossible in a well
insulated house. I can do 2000 sq. ft. for less than $100

As for the people living there, they add to the total heating, not to the
cost.

Body functions = heat
Light bulbs = heat
Computer = heat
Cooking = heat
Washing + drying clothes = heat

Larry Jaques says...

Put a small sprinkler up there and plumb it indoors so you can turn
it on and off at will.

That's an even better idea. Thanks.

"Hax Planx" wrote in message
.net...
My ancient detached shop/garage has an uninsulated roof and now that
temps are parked in the 90's with full sunshine most days, the heat
radiating from the roof turns it into an oven. Things inside (like
projects) get warm to the touch and the ambient temperature soars to
about 105°(40.6°C). I've had to move all glues and solvents and
anything else that might be temperature sensitive into the house. As
you can imagine, it makes things like brushing shellac difficult. Any
ideas for a cheap remedy just for the radiating heat problem? I know I
could insulate the roof, but that isn't the direction I want to go with
this space. Before winter sets in, I want to frame about half of the
inside of the building into a room for the wood shop and insulate that,
but I didn't want to do it now. The building is about a 1000 sq/ft and
the roof is over 12' high at the peak, so that isn't very practical
anyway. I was thinking along the lines of maybe using a reflective
coating for the roof or tacking down tarps to cut down on the heat
absorbing properties of the black shingles. Does this sound practical
at all?

I'd say you need to put in some roof vents. If the air inside is hotter than
the air outside then it will try to escape upwards. If you have no
ventilation in the top half of your building then the heat has no place to
go. Thing to remember is, if you ventilate the top of your building, you
need to allow intake vents in the bottom half of your building too. Vents
come in all types and sizes some powered others not. I've had good luck
cooling my houses attic crawlspace and workshop (small as it is it don't
take much..) with Whirly turbine type nonpowered vents. These are the
spinner type you see on warehouses and such. They are cheap and effective.
Venting isn't the cure all answer, but it is an affordable starting place.
Good luck getting the heat out.

Aloha...
Craig

Leon says...

No, not really by definition, although its purpose is pretty much the same.
It reflects the heat rather than stops its movement into a cooler area.
Insulation pretty much absorbs heat.

Ah, takes me back to my college physics days. The reason why insulation
and a radiant barrier are needed is because heat can be transferred in
two ways: by physical contact of one substance that is hotter than the
one next to it, or by infrared radiation. Insulation protects against
the first type of heat transfer, but like you said, unless it
incorporates a reflective barrier, which a lot of it does now, it will
absorb infrared along with the rest of the house. This is bad in both
the summer and winter. In the summer, your house, including the
insulation, absorbs infrared from the sun. Then long after the sun goes
down, your house may still be hot and sticky because it has stored all
that energy and continues to radiate it onto you. It is bad in the
winter because when it absorbs the infrared, it eventually must radiate
it away, but the radiation goes in every direction. Some goes back into
your house (good), some is radiated away (bad). When IR hits a
reflective material, it bounces off instead of being absorbed. Infrared
isn't heat, it becomes heat when it is absorbed by some material.
Infrared barriers act the same way a mirror does, which is why they are
bright and shiny. Infrared barriers are good in summer and winter
because in the winter, it reflects the infrared back into your house
heating some object that can absorb it, and in the summer, it reflects
IR from the sun instead of allowing the material under it to absorb the
IR and beam it inside.

I know that's more than anybody wanted to know, but since I spent five
years cramming on this stuff, it should be useful for something.

"Hax Planx" wrote in message
.net...
I asked about radiant barrier paint
today at a box store and the paint guru said they had glow in the dark
paint and fluorescent colors. I said nothing and walked away with a
permanent loss of an IQ point.

I believe the radiant paint is a Sherwin Williams product. And, I
believe it is available as an interior wall paint, in colors for those
rooms that catch a lot of sun on their exterior walls. I've heard it
opined that if you are not going to condition the space then insulation
is not the way to go. But, maybe that's just for high humidity locales
like Houston.
I'm also not a fan of blown-in cellulose insulation. I'd be afraid
it will break down as the years go by, make dust. Not to mention the
chemicals it's likely treated with.

--
"New Wave" Dave In Houston

On Tue, 28 Jun 2005 10:21:13 -0500, Hax Planx
wrote:

Any
ideas for a cheap remedy just for the radiating heat problem? I know I
could insulate the roof, but that isn't the direction I want to go with
this space.

Have you considered installing a fan in the wall near the peak of the
roof, where the heat collects? If you do that, and open a window at
your level, it should cool the place down fairly quickly and
signifigantly. Even a good size passive vent might help quite a bit.

On Tue, 28 Jun 2005 18:15:34 -0500, Hax Planx
wrote:

TheNewGuy says...

How about actively removing the heat: a gable-mounted exhaust fan, with
or without a thermostat control. Depending on the CFM, you'll need a
certain area of "inlet" into your shop of fresh air - got a screened
window?

The collateral benefit to the exhaust fan is it moves out the fine dust
too.

-Chris

A gable fan and vent system would be nice, but it is a cinder block
building and the cinder blocks go all the way to the crown. Would a fan
really cut down much on the radiant heat?

It dropped the temperature in my old shop from scorching hot to
whatever temperature it was outside in a matter of minutes, and it
sounds like you have exactly the same situation in yours. IIRC, they
had some vent fans that mounted directly to the inside of the roof
right next to the ones mounted on the wall at the hardware store, so
that may be easier.

Prometheus says...

Have you considered installing a fan in the wall near the peak of the
roof, where the heat collects? If you do that, and open a window at
your level, it should cool the place down fairly quickly and
signifigantly. Even a good size passive vent might help quite a bit.

Most people are recommending vents and fans, but it is a cinder block
building and they would be difficult to install.

Prometheus says...

It dropped the temperature in my old shop from scorching hot to
whatever temperature it was outside in a matter of minutes, and it
sounds like you have exactly the same situation in yours. IIRC, they
had some vent fans that mounted directly to the inside of the roof
right next to the ones mounted on the wall at the hardware store, so
that may be easier.

If they are in the roof, what about rain? Or maybe you are talking
about a hooded vent?

D. J. MCBRIDE says...

I believe the radiant paint is a Sherwin Williams product. And, I
believe it is available as an interior wall paint, in colors for those
rooms that catch a lot of sun on their exterior walls. I've heard it
opined that if you are not going to condition the space then insulation
is not the way to go. But, maybe that's just for high humidity locales
like Houston.
I'm also not a fan of blown-in cellulose insulation. I'd be afraid
it will break down as the years go by, make dust. Not to mention the
chemicals it's likely treated with.

Thanks. I'll look at Sherwin Williams products.