Garage Ventilation

[TurboEuro88]

I've got a 450sqft garage I am in the middle of renovating and one of the items I've been thinking about trying to tackle is air handling, specifically ventilation. The garage doesn't have any windows, ridge vents (that I can see), or gable vents. There's very little air movement or exchanging with the garage door closed, and being that the garage structure is completely open (ie. Rafters are open to garage space - no ceiling) it gets HOT in there during the summer. I intend to insulate the entire garage later this year before the following winter comes, meaning walls, garage door, and rafters (don't want to put a true ceiling in). But for the time being I am looking for ways to better manage the heat.

That all being said, what is the best route to go? Is adding a gable vent enough? I can easily wire in an exhaust fan of some kind as well, but don't know what products out there would work best. Don't really want to let too much cold air in during the winter, either. Open to any thoughts or suggestions on how to approach this.

 

[bdbecker]

A gable fan isn't a bad idea, but also make sure you have an intake vent of some sort so air can move through the space. You could make an insulated box that fits around the fan that you can install/remove with the seasons to keep the warm air in during the winter. Disconnect or unplug the fan when you cover it so you don't accidentally have it running when covered.

 

[67carl]

Gable fan with some type of opening on the opposite side of the garage. That's how I did mine. Cut an opening between the studs, added a metal louver on the outside, wired in a timer, good to go.

 

[Marctrees]

https://www.garagejournal.com/forum/showthread.php?t=363857

 

[rayra]

gable fan / vent, powered roof vent.

I've got passive vent grills in the offside wall, high and low, on my attached 2-car and I even put a high flow bathroom vent fan blowing out the high vent. really hot days I switch that fan on overnight to help eject the hot air and accelerate the garage cool down before the next hot day.
My garage is roughly 4400cu'. Typical bathroom fan is 60-80cfm. So it vents the full volume of air in an hour. which doesn't seem like a lot. But the fan is near the ceiling, so it's blowing out the hottest air. Convection does the rest.
When I hard-wired the wall switch for the fan I should have put in a timer. But I'm up late and the wife's out early, so it gets shut off at about the coolest point anyway.

 

[TurboEuro88]

Thanks for the replies. I definitely will be adding a gable vent to one end of the garage, and it sounds like adding a power vent at the other to push the hot air out is going to be my best bet. Not sure which kind of fan I'll go with though. A bathroom vent would work and by my math would exchange the volume of my garage in about an hour, but for not too much more money I can get a proper gable vent fan like one of these and exchange the entire volume of the garage in less than 10 minutes. Probably overkill...

Never had to cut siding that's already installed, though. Only ever done it pre-installation. Probably going to be easiest to just remove the siding to cut out the vents. Should be interesting...

 

[Jackfre]

Check out Tjernlund.
https://www.tjernlund.com/xchanger_basement_fan.htm
They have an assortment of excellent ventilation products. The Xchanger is only one of them.

 

[bing98]

I plan on doing some painting in the the garage so I chose a squirrel cage blower. A local HVAC company was nice enough to let me pick through their "bone yard" before the recycler came. I pulled 3 blowers out of some old forced hot air systems.

I have installed one of the smaller ones in a basement window. This allows me to use my wood tools and do some light spraying in the basement.

I installed the biggest one in my garage wall. It has a selector switch so I can change the speed. It's a small 1-car so it gets tight in there sometimes. So, installed a power switch on each side of the garage so if I'm working on the car I can turn it on or off without having to crawl over things. Works like a charm. I have spray painted and sand blasted in the garage with no issues. This thing turns the air over in probably a minute.

This might be too big for what you're looking for, but it was virtually free. On low speed it ***** much less are. I'm sure you wouldn't have a problem finding one locally.

 

[homelessdespot]

Could you post a picture? That's a very good idea. Thinking about woodworking in the basement but would need dust collector and ventilation somehow.

 

[old_smokey]

I put in a bathroom exhaust fan in my little one-car garage. I have a flat, insulated ceiling, so the fan sits on top in the attic space. There is a one-way air valve/flap at the fan, and another at the exhaust point at the gable. That helps keep the cold air from getting in. The 'ducting' is just abs pipe surrounded in insulation to help prevent heat loss in winter where it passes through the ceiling.

Just a basic setup, but it's amazing how well it works. I use the space for mostly motorsports mechanic work and solvents/gas/etc gets smelly in a small tight space. Running that fan for a few minutes works wonders. I can hear the fresh air getting sucked through the bottom of the man-door. Anyway, just a +1 on a fan that ***** air from up top and out the gables.

 

[Marctrees]

turbo - Do what you wish, but I would never choose that chinese fan you linked when there is stuff like J&D.

Like I said... check delivered price from Global.

Marc

 

[bing98]

Here's some pics of my ventilation. Nothing fancy, but effective. As with everything I do it has to be low budget.

Basement
This basement window was toast and boarded up when we moved in so I just built a new wooden insert with a sliding door to keep the critters out. It's removable so I can pull it out when I have time to rebuild the window frame. I still need to hook this one up to a rotary switch. I used this on in the garage. Seems to be very well built and reasonably priced. https://www.amazon.com/gp/product/B009IS73I2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Garage
This is the one with the two power switches(one on each side of the garage) and speed selector. The exhaust passes through a hinged vent that I got from an old industrial A/C unit my company tossed. I have a screen inside the exhaust to keep the bugs out. This thing ***** the doors closed so it probably ***** god knows what in through and cracks or pin holes in the garage so I still have to create a filtered intake. I'm also going to encase the blower in a chamber with two filters so I'm not blowing too much outside.

 

[Marctrees]

bing - Very effective and bang for buck.



Marc