My Own Private Hell: Cooling a Windowless Garage Workshop
by Patrick Harper - Blood, Sweat, and Sawdust
The heat really has me down. This past week was a scorcher. Fortunately, the air was cool this morning. So, I got up early and finished installing the radiant barrier in the small attic above the garage. Time will tell if this offers any really benefit. The forecast for the next few days is cooler.
Last week I took a few temperature readings with my infrared temp gun. I took all readings at 4pm on a sunny day with temps in the mid nineties. The ambient temperature was around 85 degrees in the shop. Not terrible, but enough to have me sweating profusely when doing any handwork. The relative humidity was around 70%. The interior walls all read around 80 degrees, but the ceiling near the attic space read 95 degrees. This has convinced me that the attic space is contributing to the heat in the garage to some degree.
This piqued my curiosity, so I took a few readings in the attic space. The ambient temperature was around 110 degrees. What surprised me was that the attic ceiling read 135 degrees. I bought 3 rolls of Reflectex radiant barrier insulation the next day. I ran out of the reflective tape, so I still need to finish taping up the seams. As soon as I get another hot day, I will take another round of temperature readings, and report back.
Installation of the radiant barrier is straight forward. It’s sold in various widths that correspond to common spacing of your rafters. You simple staple it between two rafters, every 6 inches or so. The instructions said to leave a 3-6 inch gap at the top if you have a ridge-line vent.
I’m hoping that this will lower the ambient temperatures in the garage by about 5 degrees. The other factor contributing the my discomfort is the humidity. I plan to buy a dehumidifier or portable AC with dehumidifier. The portable units aren’t the best, but I think a 12000 btu unit could cool my insulated garage down to 75 degrees. I would consider a minimalist, but I just don’t know how much longer I’ll be in this house.
What have you done to cool down your shop?
Cooling a windowless garage in the southeast ain’t easy.
Click here for part II: cooling a windowless garage with a portable air conditioner.