Help Design New Detached Garage Ventillation

[HuD_91gt]

We just received our permits for our home including a detached 16x33’ garage. This will be home to a 4 post lift at the garage door, and a workshop on the rear half.

I do a lot of welding and I am trying to get ahead of the builder on garage ventilation.

For general air circulation for dust and fumes, I was planning on running a series of furnace filters, inline charcoal filters etc to clean the air.

I have no idea where to start for ventilation. This garage is in a tight city lot where noise is a concern, and I will be making noise. It will be fully insulated, and a mini split installed. I’m my mind, any sort of ventilation is a source for noise. What about heat loss/efficiency?

I did some searching and see something called an HRV? Is this a form of heat transfer system?

I live in the PNW. Mild winters and summers are never extreme for very long.

 

[ericm]

Heat Recovery Ventilation. New houses are so tight that they need a way to bring in fresh air. The HRV does that while conserving heat so your fresh air isn't cold or hot. Basically heat is pulled from air to be exhausted and passed to the incoming fresh air, or the reverse if it's hot out and the space is conditioned. An ERV does the same while also conserving humidity. They're mostly used in the south. Your house may have one (code requires them in a lot of places). Small ones don't cost much and could be used to bring fresh air into the garage without having to heat/cool the fresh air.

There's some shop folk on youtube who have added extensive filter systems to their mini splits. The filters that come with them are pretty weak. There are also filtration units made for shops, mostly wood shops. They're not all that expensive either.

 

[chinboys]

Exhaust air leaving the space has to be made back with new air passively via openings. The openings can have screens and filters attached but overtime the clogging of the medium with dirt, etc will decrease the makeup air thus causing the exhaust air volume to decrease. You will find your space to be of a lower air pressure relative to the outside air pressure thus the space will leak air from the outside. This will bring in dirt.
I would use an active makeup air fan or blower that is bringing more volume of air than the exhaust volume.

 

[HuD_91gt]

Ok, so I’d like have some sort of fan to bring in fresh air, and one to exhaust air if I’m not concerned about efficiency. Or add a cheap HRV.

Can these inlets/outlets be out the roof?

I will have residential housing on the 2 most convienient sides of the home for ventilation. I feel like noise will also be venting. The one open side of the home has a prevailing wind which I assume would be poor for exhaust ventilation.

The backside of the garage is a prime area to exhaust but is right next to a house. Can I add some sort of muffler system to the exterior vent (hopefully outside as I’m space limited and it wouldn’t be able to be seen due to a large hedge).

 

[Dagny]

An HRV will be very quiet. would not use one for welding fumes.

 

[thunderskunk]

In the same boat with the added issue of venting a household over the garage.

 

[pcmeiners]

For general air circulation for dust and fumes, I was planning on running a series of furnace filters, inline charcoal filters etc to clean the air.

Unless charcoal filters have literally a >ton of activated charcoal it is totally useless. The thin charcoal filters in all retail filters are just fluff for sales purposes, good for about 3 minutes. Some of the HEPA filters can filter very low micron particles but no particle filter traps all particles

 

[HuD_91gt]

I was looking into the ones that are sold for the Marijuana grow industry. But certainly won’t be a ton of charcoal.

What is in a welding fume extractor?

 

[HuD_91gt]

Something along these lines.

AC Infinity Australian Charcoal Carbon Filter 10 INCH (1249 CFM)

Buy AC Infinity Australian Charcoal Carbon Filter 10 INCH (1249 CFM) now at Indoor Farmer!

indoorfarmer.ca

 

[ambenz]

I would just get a Fume Extractor on a articulating arm.....

Flexible Welding Fume Extraction Arm/Capture arm Fume Extractor Arms/Dust Suction Arm​

Anything else is really overkill as these exhaust fume pretty good. No matter how well you prep for heat loss, your overhead doors are loose enough to allow seepage of outside air. Only run it when you are welding as you can pinpoint an are to extract right on your table!

 

[HuD_91gt]

That’s not a bad idea at all. Direct it outside the shop.

Some sort of fresh air would still be required, as I assume the leakage past the doors wouldn’t be enough?

Saying that, I could just crack the garage door when welding for inlet air.



The more I think about it, the better this solution sounds. Thanks.