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  1. walta100 | | #1

    The way I see it as long as the space is unconditioned and the attic is vented you can’t go wrong.

    The wife insisted we insulate the unconditioned garage. I must say it is nice in the winter getting into a somewhat warm car in the winter. It is also irritating in the summer to walk into a garage 98° at 9PM and it is 80 ° outside.


    1. Deleted | | #2


  2. walta100 | | #3

    Insulation does not stop the flow of heat it does slow the flow of heat. Whatever the outdoor temp is if given enough time the indoor temp will be the same as the outdoor temp.

    This time of year the sun beats down on the garages from 5AM to 8PM. If you happen to open the garage doors to get a car out about 9AM and let out coolest air out and replace it with warmer air then again at 6PM change the air out again and park a hot machine in the garage. So on a day when it gets to be 105° it would it not be a surprise if it was over 90° in the garage at 8PM. Then a line of storms move thru the outdoor and the outdoor temp falls to 80°.

    Now that I think of it, it is almost always warmer in the garage than outdoors summer and winter.


  3. BirchwoodBill | | #4

    I am in White Bear Lake, MN. 2x4 garage with gable roof and siding. I furred out the walls and installed 5.5 inches fiberglass batts with Kraft paper. Drywall on walls and ceiling. For the attic, I placed 1 inch foil base rigid foam and then taped the seams, so the vent runs up to the peak. I have a plywood floor in the attic, so the insulation is only 5.5 inches. The garage does get stuffy in the summer, should have installed some self closing awnings.

    1. Deleted | | #5


  4. walta100 | | #6

    I would not use the word stuffy.

    I doubt anyone would build an unvented uninsulated garage most uninsulated garages are well vented.

    I must grudgingly admit I like the insulated garage the wife wanted. It is sometimes shockingly hot some days in the summer but overall it is a great luxury.


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