Garage ventilation

JHZR2

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I have a 10 bay garage, each bay is partitioned from the next, and each bay has a sliding barn door to keep the elements out. They are not sealed. They have combination gravel and cement floors.

The entire building has a gable roof, around 120’ total length. All the bays are partitioned so there really isn’t a way to mix air or flow from one to the next. Id like to keep some airflow in my two adjacent bays where I have a little workshop (and there is the ability for some cross-flow). It is terribly hot in there in the recent heat wave, no air mixing, just stagnant, even with a box fan blowing across the space. Im thinking some sort of small exhaust fan like is used in a Bathroom, just to force more exterior air all the time. I tried a 4” booster fan, it was way too weak. I’m thinking some bathroom fan as it’s considered an originating air handling device, not a booster, and may be able to keep its cams with more drop over a longer length.

I don’t want to spend a ton, but I do want to get some airflow since the gravel tends to allow water vapor to rise up through. I’d prefer not to put any fan on the roof. Any suggestions thst aren’t too big or small?
 
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manicrodder

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I have a 10 bay garage, each bay is partitioned, each bay having a sliding barn door to keep the elements out. They are not sealed. They have combination gravel and cement floors.

The entire building has a gable roof, around 120 total length. All the bays are partitioned so there reslly isn’t a way to mix. Id like to keep some airflow in my two adjacent bays where I have a little workshop. It is terribly hot in there, no air mixing, just stagnant Im thinking some sort of small exhaust fan like is used in a Bathroom. I tried a 4” booster fan that i tried, it was way too weak. I’m thinking some bathroom fan as it’s considered an originating air handling device, and may be able to keep its cams with more drop over a longer length.

I don’t want to spend a ton, but I do want to get some airflow since the gravel tends to allow water vapor to rise up through. I’d prefer not to put any fan on the roof. Any suggestions thst aren’t too big or small?
I had a small evaporative cooler that was on wheels. Use it with water or just air.
 
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What is the roof ventilation like? Ridge, gable vent, soffit vent. I am wondering if opening them up (make bigger) might help with passive airflow, then add fans to help.
 
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MG_1556-min_32e9099a-ceb3-42df-b43a-05bb4e66b92b_200x.jpg
 
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Harbor Freight sells 24 inch pedestal fans, and one model that sits on the floor, if that works better for you. They really move the air around. My last job was in a warehouse with no air movement, and they made all the difference in the world. I think they sell for $119 a piece.,,
 

Nick1994

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View attachment 63759
Exactly what I was going to post.
 
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Are you trying to just move air around, where BigCahuna's idea would work? Or are you trying to exhaust stale air and introduce fresh air? Maybe both?

If you install an exhaust fan, remember that it creates negative pressure in that room and makeup air will enter from wherever most easy. If you do not provide a fresh air intake vent, you might simply draw stale air from the other garage bays (still uncomfortable).

People sometimes put exhaust fans in home attics improperly, negative pressure then draws conditioned air out of the living space through cracks. You need to put some thought into installation and location of an exhaust fan , with proper air intake also considered.
 

JRed

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Depending on how much air you need to move and portability requirements you could get something like a confined space blower with a long enough hose to set the fan in fresh air and blow it into your workshop.
 
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View attachment 63759

This is a good idea. Mount it high. Are the bay partitions floor to ceiling or is there a gap from top of partition to the ceiling?

Measure your cubic feet inside and buy enough of these fans to accomplish the task. You have a decent size building there.
 
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How much trouble would it be to seal off the 2 bays from the rest of the garage/elements and put a mini split in? If it’s a real old garage this may be more work than you want to do at this point but it’s a thought. Pictures would help.
 

Kestas

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I have hydraulic issues in my garage where water vapor comes up through the floor. My house is built on a swale among homes that sit on hills. I manage the garage with a dehumidifier that dumps the water through a hose that runs under the garage door.

If I don't run a dehumidifier, the underside of my cars become dripping wet with water and things rust.
 
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I have a 10 bay garage, each bay is partitioned, each bay having a sliding barn door to keep the elements out. They are not sealed. They have combination gravel and cement floors.

The entire building has a gable roof, around 120 total length. All the bays are partitioned so there reslly isn’t a way to mix. Id like to keep some airflow in my two adjacent bays where I have a little workshop. It is terribly hot in there, no air mixing, just stagnant Im thinking some sort of small exhaust fan like is used in a Bathroom. I tried a 4” booster fan that i tried, it was way too weak. I’m thinking some bathroom fan as it’s considered an originating air handling device, and may be able to keep its cams with more drop over a longer length.

I don’t want to spend a ton, but I do want to get some airflow since the gravel tends to allow water vapor to rise up through. I’d prefer not to put any fan on the roof. Any suggestions thst aren’t too big or small?

I don't have anything to add other than I need a space like this in my life. Carry on.
10 bays!!! 10!!

Midas? Mavis Discount Tire?
 
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I have a 10 bay garage, each bay is partitioned, each bay having a sliding barn door to keep the elements out. They are not sealed. They have combination gravel and cement floors.

The entire building has a gable roof, around 120 total length. All the bays are partitioned so there reslly isn’t a way to mix. Id like to keep some airflow in my two adjacent bays where I have a little workshop. It is terribly hot in there, no air mixing, just stagnant Im thinking some sort of small exhaust fan like is used in a Bathroom. I tried a 4” booster fan that i tried, it was way too weak. I’m thinking some bathroom fan as it’s considered an originating air handling device, and may be able to keep its cams with more drop over a longer length.

I don’t want to spend a ton, but I do want to get some airflow since the gravel tends to allow water vapor to rise up through. I’d prefer not to put any fan on the roof. Any suggestions thst aren’t too big or small?
This may sound elementary, but some sort of set-up with a lot of fans to direct airflow. If done very optimally, I've had it so good I didnt even need to turn AC on.

Try to draw the air from a cooler space (low and in the shade?) and blow it at angles across open spaces as effectively as possible. Maybe between bays. Whatever super powerful Vornado or Honeywell or whatever kind of fans that are basically shaped like jet engines and thrust air as fast as possible like again basically a jet engine.

You are controlling the airflow and yeah it is HOT.
 

JHZR2

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I had a small evaporative cooler that was on wheels. Use it with water or just air.
It is so humid here I don’t think that would work. And I don’t really want more moisture in the space. What I want to avoid is the hot, stagnant air, that gets moisture coming up from the gravel floor after it rains and the ground is wet. It just makes for a nasty hot environment, much less comfortable than when you step outside.
 

JHZR2

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What is the roof ventilation like? Ridge, gable vent, soffit vent. I am wondering if opening them up (make bigger) might help with passive airflow, then add fans to help.

Currently none. It’s just an old building with no
Real sealing or air-tightness. No design of the roof to vent.


Are you trying to just move air around, where BigCahuna's idea would work? Or are you trying to exhaust stale air and introduce fresh air? Maybe both?

If you install an exhaust fan, remember that it creates negative pressure in that room and makeup air will enter from wherever most easy. If you do not provide a fresh air intake vent, you might simply draw stale air from the other garage bays (still uncomfortable).

People sometimes put exhaust fans in home attics improperly, negative pressure then draws conditioned air out of the living space through cracks. You need to put some thought into installation and location of an exhaust fan , with proper air intake also considered.

Moving air around doesn’t help much. The hot air from up at the roof just mixes around and it’s not comfortable. It needs to be exterior air coming in. I think it will need to be one per bay.


Depending on how much air you need to move and portability requirements you could get something like a confined space blower with a long enough hose to set the fan in fresh air and blow it into your workshop.
sort of what I’m thinking…


This is a good idea. Mount it high. Are the bay partitions floor to ceiling or is there a gap from top of partition to the ceiling?

Measure your cubic feet inside and buy enough of these fans to accomplish the task. You have a decent size building there.
Yes, floor to ceiling. I have some bays rented so I don’t want to remove partitions.


I have hydraulic issues in my garage where water vapor comes up through the floor. My house is built on a swale among homes that sit on hills. I manage the garage with a dehumidifier that dumps the water through a hose that runs under the garage door.

If I don't run a dehumidifier, the underside of my cars become dripping wet with water and things rust.

I haven’t seen dripping wet undercarriage, but it makes sense and is worth watching. I’ve found that it’s all ok until the days come where the vehicle is cold, the air is humid, and I open the doors, which results in mixing.

so control over ventilation, maybe based upon humidity, is important. It may need to be enough air exchange to ensure thermal equilibrium. Not sure that’s viable.
 

JHZR2

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How much trouble would it be to seal off the 2 bays from the rest of the garage/elements and put a mini split in? If it’s a real old garage this may be more work than you want to do at this point but it’s a thought. Pictures would help.
The dehumidification aspect is attractive, but the leakiness of the building would make it extremely wasteful.
 
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Yes, floor to ceiling. I have some bays rented so I don’t want to remove partitions.


No need to remove but lower the solid partition height and install chain link or similar to allow for cross ventilation.
 
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