# Garage has no wall insulation... Wanting to cool it before the REAL Summer heat



## jonathanwb (Apr 28, 2020)

Hi,

Just found out after a water heater flood that my garage has zero insulation in its walls. It has a good amount in the attic ceiling, but the walls are hollow. I live in SoCal and the space has been almost unusable in the Summer past 90 degrees. Because this space is becoming more used, I'm wondering what I can do to help this. Attic radiant barrier, blown-in insulation ???

Thanks
(and yes, those are my clay roof tiles laying on the rafters lain

20' x 20' space
Two small screened windows
Side access w/security screened door
Two 52' ceiling fans


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## Windows on Wash (Aug 30, 2011)

Never gets to freezing I take it?


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## jonathanwb (Apr 28, 2020)

Nope... getting warmer though as the years go by :devil3:


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## Windows on Wash (Aug 30, 2011)

Yep. Wall insulation, radiant on the underside of the rafters to (hopefully a vented roof), insulation on the attic floor.


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## jonathanwb (Apr 28, 2020)

Thanks... yeah the roof is a European design built for ventilation. Doesn't work that well though in the Summer. If I went the Radiant Barrier route, I'd leave a gap near the top so the heat could radiate out. Wall insulation would have to be blown in from the outside. Sounds like I'm on the right path.


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## House Designer (Oct 4, 2019)

Unless you are planning to add HVAC, I don't think insulating the walls will have any effect on lowering the temperatures in your garage. The attic insulation should be keeping the attic heat from moving downward, so just ensure that you have adequate attic ventilation. As for the garage space, if it gets hotter than the ambient temperature, just open windows and doors and use fans.


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## jonathanwb (Apr 28, 2020)

Thanks, you make a good point. The contractor said I had to tear out the existing drywall to add insulation due to horizontal fire-blocks in the construction. That's not happening soon. I'll add the radiant barrier, some larger ceiling fans, insulation in the opened areas and stop there.

Thanks everyone!


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## user_12345a (Nov 23, 2014)

Have you thought about a whole house style fan?

Would need sufficient attic ventilation as well as have make-up air.

Cool the place down at night with the fan, seal it up during the day.


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## rmoore853 (May 2, 2020)

There are portable options to cool down the garage. Opening the garage door welcomes a big breath of fresh air. You can also add powerful portable fans or a dehumidifier. Building a low- tech swamp cooler is a good option too. Or you can install a portable air conditioner.


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## HenryMac (Sep 12, 2018)

Just insulate the walls 1st. See how that works.

Do you live in an area where forest fires are an issue? If the answer is no then a big ole gable end vent would help let some of the heat out of the attic.

Roof vents in a forest fire prone area can be bad news... it's a great place for embers to enter the structure.


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## NeoHawk (Jun 13, 2020)

Some of the recent model ductless and/or zone A/C units are very efficient so that may be worth investigating the cost/benefit for temp moderation in that space. Two cents.


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