After a snow here in the NW, we often get the "pineapple Express," warm
moist air from Hawaii.

This causes a huge amount of water to condense in my hangar. The floor will
have 1/8 inch of water on it. This has only happened once in 5 years. But
today I bought a couple of big fans and plan to cut holes in the hangar door
and continuously vent with the fans.

Do you think I should blow air in, or out. Or should one be in and the other
out. Or is this just a dumb idea and something else would work much better.
The builder of the hangar did not consider condensation and there are no
roof vents.

Best,
Karl
"curator"

Where are you in the northwest?

I assume that you have a metal roof. It needs to be insulated. My
rented hanger has an uninsulated metal roof. When frost or snow
accumulates on the roof, then is warmed by the sun: drippy ceiling.
Conversely, my shop building at home has a metal roof with 2 inches of
fiberglas insulation: No drip. No wet insulation.

Al
KSFF/Spokane, WA

karl gruber wrote:
> After a snow here in the NW, we often get the "pineapple Express," warm
> moist air from Hawaii.
>
> This causes a huge amount of water to condense in my hangar. The floor will
> have 1/8 inch of water on it. This has only happened once in 5 years. But
> today I bought a couple of big fans and plan to cut holes in the hangar door
> and continuously vent with the fans.
>
> Do you think I should blow air in, or out. Or should one be in and the other
> out. Or is this just a dumb idea and something else would work much better.
> The builder of the hangar did not consider condensation and there are no
> roof vents.
>
> Best,
> Karl
> "curator"
>
>

My uninsulated, unheated, drafty hangar would do this with regularity. My
insulated, heated, tight as a drum hangar never does it. I think the key is
keeping the insides warm which keeps the humidity down. When the warm moist
air does make an appearance it seems the low humidity in the hangar is able
to absorb the added moisture without condensing.


"karl gruber" > wrote in message
...
> After a snow here in the NW, we often get the "pineapple Express," warm
> moist air from Hawaii.
>
> This causes a huge amount of water to condense in my hangar. The floor
> will have 1/8 inch of water on it. This has only happened once in 5 years.
> But today I bought a couple of big fans and plan to cut holes in the
> hangar door and continuously vent with the fans.
>
> Do you think I should blow air in, or out. Or should one be in and the
> other out. Or is this just a dumb idea and something else would work much
> better. The builder of the hangar did not consider condensation and there
> are no roof vents.
>
> Best,
> Karl
> "curator"
>

The hangar is at Bremerton. It has about 6 inches of insulation on the
ceiling. One wall is on the outside end of the hangar row and has a fire
wall on that side. Just metal is between the individual hangars.

Best,
Karl
"Al" > wrote in message
. ..
> Where are you in the northwest?
>
> I assume that you have a metal roof. It needs to be insulated. My rented
> hanger has an uninsulated metal roof. When frost or snow accumulates on
> the roof, then is warmed by the sun: drippy ceiling. Conversely, my shop
> building at home has a metal roof with 2 inches of fiberglas insulation:
> No drip. No wet insulation.
>
> Al
> KSFF/Spokane, WA
>
> karl gruber wrote:
>> After a snow here in the NW, we often get the "pineapple Express," warm
>> moist air from Hawaii.
>>
>> This causes a huge amount of water to condense in my hangar. The floor
>> will have 1/8 inch of water on it. This has only happened once in 5
>> years. But today I bought a couple of big fans and plan to cut holes in
>> the hangar door and continuously vent with the fans.
>>
>> Do you think I should blow air in, or out. Or should one be in and the
>> other out. Or is this just a dumb idea and something else would work much
>> better. The builder of the hangar did not consider condensation and there
>> are no roof vents.
>>
>> Best,
>> Karl
>> "curator"

I wish my hangar were so tight!

It would take more money than I'd like to spend to somehow screen off the
hangar doors (they are on both sides and you can drive straight through) and
insulate the other walls. I am hoping to do this with venting....but don't
know.


Karl



"Dave Stadt" > wrote in message
et...
> My uninsulated, unheated, drafty hangar would do this with regularity. My
> insulated, heated, tight as a drum hangar never does it. I think the key
> is keeping the insides warm which keeps the humidity down. When the warm
> moist air does make an appearance it seems the low humidity in the hangar
> is able to absorb the added moisture without condensing.
>
>
> "karl gruber" > wrote in message
> ...
>> After a snow here in the NW, we often get the "pineapple Express," warm
>> moist air from Hawaii.
>>
>> This causes a huge amount of water to condense in my hangar. The floor
>> will have 1/8 inch of water on it. This has only happened once in 5
>> years. But today I bought a couple of big fans and plan to cut holes in
>> the hangar door and continuously vent with the fans.
>>
>> Do you think I should blow air in, or out. Or should one be in and the
>> other out. Or is this just a dumb idea and something else would work much
>> better. The builder of the hangar did not consider condensation and there
>> are no roof vents.
>>
>> Best,
>> Karl
>> "curator"
>>
>
>

"karl gruber" wrote:
> After a snow here in the NW, we often get the "pineapple Express," warm
> moist air from Hawaii.
>
> This causes a huge amount of water to condense in my hangar. The floor will
> have 1/8 inch of water on it. This has only happened once in 5 years. But
> today I bought a couple of big fans and plan to cut holes in the hangar door
> and continuously vent with the fans.

The problem is the concrete's temperature. It has been cold-soaked below the
ambient air's dewpoint. Until the former rises or the latter falls, there's
no stopping the condensation.

Forced air venting will help the floor warm up more quickly. The most
effective remedy would be to apply radiant heat to the floor, but that could
get expensive.

> Do you think I should blow air in, or out. Or should one be in and the other
> out. Or is this just a dumb idea and something else would work much better.


In & out would be best. You want a lot of air changes/hour to warm the floor.

--
Dan
T-182T at BFM

I had that happen in my hanger. When I put in two cieling fans and keep
the air circulating, it never happend again. The air in motion can hold
a lot more moisture. Previously the dehumidifier was not able to fix it.
The cieling fans run continously at about 50 percent, blowing air down.
One time I went into my hanger (before fans) and there was a cloud in
there. And you could make out the cloud base about 10 feet up. And
everything was dripping wet. Well that's my expierience.

John

karl gruber wrote:
> After a snow here in the NW, we often get the "pineapple Express," warm
> moist air from Hawaii.
>
> This causes a huge amount of water to condense in my hangar. The floor will
> have 1/8 inch of water on it. This has only happened once in 5 years. But
> today I bought a couple of big fans and plan to cut holes in the hangar door
> and continuously vent with the fans.
>
> Do you think I should blow air in, or out. Or should one be in and the other
> out. Or is this just a dumb idea and something else would work much better.
> The builder of the hangar did not consider condensation and there are no
> roof vents.
>
> Best,
> Karl
> "curator"
>
>

On Sep 19, 8:02 am, The Visitor > wrote:
> I had that happen in my hanger. When I put in two cieling fans and keep
> the air circulating, it never happend again. The air in motion can hold
> a lot more moisture. Previously the dehumidifier was not able to fix it.
> The cieling fans run continously at about 50 percent, blowing air down.
> One time I went into my hanger (before fans) and there was a cloud in
> there. And you could make out the cloud base about 10 feet up. And
> everything was dripping wet. Well that's my expierience.
>
> John
>
> karl gruber wrote:
> > After a snow here in the NW, we often get the "pineapple Express," warm
> > moist air from Hawaii.
>
> > This causes a huge amount of water to condense in my hangar. The floor will
> > have 1/8 inch of water on it. This has only happened once in 5 years. But
> > today I bought a couple of big fans and plan to cut holes in the hangar door
> > and continuously vent with the fans.
>
> > Do you think I should blow air in, or out. Or should one be in and the other
> > out. Or is this just a dumb idea and something else would work much better.
> > The builder of the hangar did not consider condensation and there are no
> > roof vents.
>
> > Best,
> > Karl
> > "curator"

Any uninsulated metal building will suffer condensation if
enough humidity is present. The metal roof or sides radiate heat off
very quickly, much more quickly than the air inside the hangar, and so
it cools more quickly and any moisture in the air inside will condense
on it. You need to either reduce the radiation losses of the metal to
space by insulating the outside (which isn't practical) or by keeping
the air inside away from the metal with insulation or vapor barriers
or both.
The radiation of heat into space is what causes frost to
form on cars and airplanes or whatever on clear nights. The metal
cools faster than the surrounding air, and moisture condenses on it.
Just being under the roof of an open carport or hangar will stop that
by reflecting the vehicle's heat back on itself.

Dan