Ventilating a Workshop
I am in the process of building a house and workshop. It is a single 32′ x 48′ building with a partition wall down the middle dividing it into two 24′ x 32′ spaces. The partition wall doesn’t have any doors or windows. You have to go outside to get from the living area to the workshop. The construction is 12″ double stud walls with 16″ TJI rafters. Both sides of the exterior walls are being air sealed as much as possible, so I expect that the building will be fairly air tight. Each side will be heated and cooled with separate mini-splits. I am in SW Wisconsin, zone 6.
On the living area side, I am installing 2 pairs of Lunos HRV’s. My question is, what to do for ventilation on the workshop side. It’s hard do define how much ventilation is needed. Seems like it could vary from less than 1 ACH most of the time to 20 or more on occasion. Activities could include woodworking, metal fabrication, and welding. Workshop volume is 8000 cu.ft. over a 684 sq. ft. floor area.
I hesitate to install an HRV because the payback on the amount of heat recovered seems pretty long. I’m considering a variable speed wall fan with about 1500 – 2000 cfm maximum and running it on low speed and/or intermittently most of the time and turning it up as needed. I would also install a passive air intake with a damper sized for low air flows and plan on opening a window for higher air flows. (I did read the article about passive air intakes not working well, but I think it may be okay in this application since it is a single room and the intake can be well sheltered.)
I would be interested in any thoughts, suggestions or experiences on this. I have been lurking and learning on this forum for the past few years while designing and building my project. The wealth of knowledge here has been invaluable!
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