Adding extra insulation...worth it??

[Black_Z28]

Hello, I have a 26x26 heated and fully finished garage that is heated by a 60K BTU Hot Dawg.

I'm wondering if adding some extra insulation to the attic of the garage is actually beneficial. I live in MN, and it frequently gets below 0 for lows, and even below 0 for highs. I don't use the garage for an everyday shop, but just an area to mess around in. I normally keep the garage at about 46 in the winter, then turn it up to about 50 if I'm going to be out there for a longer period of time.

Right now there's about 6" worth of insulation, which was added about 10 years ago, so it has compressed some. It is the blown in insulation. I was thinking about adding more blown in, or even the bats of insulation(which is better for this situation). I don't use the attic for storage, and never plan, so I could add as much insulation as I want. But, I'm wondering if it's worth adding more? Will I see a decrease in my gas usage? I figure doubling the depth would get me to a R42, which is about where I should be in the house.

Anyone have any advice? Thank you.

 

[bczygan]

Insulate.

 

[DonPowers]

I recently ran a few numbers on my 48 x 32 garage with 6" or 12" on the flat ceiling and 6" or 10" on the sloped portion of the ceiling. Came up with a potential savings of a couple hundred a year, keeping it at 65 deg. This would be about a seven year payback, longer if I keep the temperature lower.

I'm more interested having a low operating cost during retirement than the current installation cost.

Currently working on insulating the upstairs with R-46 in the flat ceiling and R-38 in the sloped portion of the ceiling, using Roxul which is R-23 @ 6" and R-15 @ 4".

Looking into using a geothermal heat pump for radiant heat and a grid-tie photovoltaic system to offset the electric cost.

 

[kd3pc]

Insulate more

I am middle TN and have 13-15" in my garage. Insulation is cheap compared to the heat wasted when there is not enough. They suggest R32-38 in our area, and it seldom gets below zero for more than a couple of days a year.

Even when 26 to 30 degrees outside, my garage is mid to upper 40's which is way better than working outside, and I have no heat. One day perhaps.

 

[Steevo]

You can never have too much, especially in MN.

 

[rburke65]

I would have to vote for more insulation.......

 

[James-W]

There is no question about it, more insulation will lower your heating bills. But you mentioned you don't use the garage all that much, your exact words were....

"I don't use the garage for an everyday shop, but just an area to mess around in. I normally keep the garage at about 46 in the winter, then turn it up to about 50 if I'm going to be out there for a longer period of time."

Depending on what your heating bills are now, and depending on what they will be after you insulate, I am not so certain the payback period would make it practical to do it. Let me give you an example of what I am trying to say.

I keep my garage at 50 degrees all the time, but when I want to work on a project I turn it up to 70 degrees. I have R-19 in the walls and R-30 in the ceiling. My heating bills during the Winter months for my garage average right around $40 per month, but that includes a $10 per month gas meter charge which will not change regardless of how much,, or how little, natural gas I use. So it costs me on average $30 per month during the Winter months here in Wisconsin. During the rest of the months all I have is the $10 per month meter charge.

Let's say that I were to add a lot more insulation and by doing so I was able to drop the cost for heating my garage in half. OK, I just saved $15 per month for maybe 4 or 5 months out of the year. The payback time would be an awful lot of years and quite frankly, I am not sure I would live long enough to pay for the insulation from the savings it give me.

Like I said at first, insulation is a wonderful thing and it will definitely save you money on your heating bills. But depending on how much insulation you already have, and depending on how much additional insulation you are planning on adding, as well as how much your current heating bills are, you need to do some calculating to see if it would be economically worthwhile to add more insulation.

 

[CNGsaves]

+1 to add more blown in insulation in ceiling. Watch for sales at Menards and do it yourself.

 

[TurboMustang370]

Most certainly insulate. My 20x20 is insulated (walls and ceiling), I have a small kerosene heater that only runs for about 15-20 minutes to get the garage to comfortable temps when ambient temps are below freezing.

 

[Black_Z28]

Looks like it would cost me about $300 to add another 6" or so of blown in insulation. Currently my heating bill is around $100, that's just this last month. But, that also includes the house. I'm just going to guess that about half of that is the garage, because both heaters seem to kick on and off at about the same intervals, and because the house heater is turned down at night while sleeping.

So, if I could just cut my bill by about 30%, then it would pay for it's self in about a year of winter months.

Maybe I'll run to menards and see if they'll let you rent their blower for a lower cost if you buy the insulation from them. My brother also works there, so maybe he could get me a further discount.

Thanks for you words of input guys.

 

[Algoma56]

Insulate. Don't forget that heat getting into attic can also melt snow, create ice which could shorten life of your roofing(shingles).
Besides the cost factor, building will heat faster.