To add attic insulation or not to add...?

[REWahoo]

I don't disagree with the envelope analogy, but I will say that my attached 3 car garage has insulation within the ceiling area (I also believe insulation is within the exterior walls). My garage essentially has no heating source other than 2 hot water heaters and the furnace and furnace duct work which sit within the garage, but yet the garage only runs about 5 degree cooler than the house itself. Without insulation I have to assume that garage would have a temperature differential much greater than 5 degrees so I believe it does help with my energy conservation. My garage does have its own Reznor gas heater, but it never runs (even during a CO winter) as I have the set point at 55 Degrees.

If it was me, I would probably price blowing in insulation above the garage when I "topped off" the house (even without insulated garage walls), as I have to believe it would help some. If the additonal cost was great since your starting with no insulation, I might change my mind (?).

Even though you don't use it as such, your garage was constructed to be heated. That's why it has wall and attic insulation, to retain the heat in that envelope.

Since the OP does not have a heated or air conditioned garage, there is no need to create an envelope to retain heat or cold. That's why adding attic insulation above the garage would be an unnecessary expense.

 

[TripleLindy]

I did the opposite of insulating the ceiling above our garage. Our garage would get so hot in the summer, I added ceiling vents to allow the hot air to escape into the attic above and a powered roof vent in that attic to vent the hot air out. Made a huge difference.

 

[REWahoo]

Our garage would get so hot in the summer, I added ceiling vents to allow the hot air to escape into the attic above and a powered roof vent in that attic to vent the hot air out. Made a huge difference.

I've thought about doing something similar but was concerned it might be a fire hazard/code violation.

 

[Sunset]

I did the opposite of insulating the ceiling above our garage. Our garage would get so hot in the summer, I added ceiling vents to allow the hot air to escape into the attic above and a powered roof vent in that attic to vent the hot air out. Made a huge difference.

My garage has a roof vent because the dumb roofers put it in before I could stop the guy.
Mine doesn't need it, as its not insulated and not tightly sealed, so you can see daylight around the doors.

I have thought of putting a fan on it to draw out the air at the top faster than a passive vent.

 

[CRLLS]

What does your electric/gas bill show? Our gas bill says we are below the average usage based on similar homes. The electricity bill says we are in the most efficient neighbors group, except for the winter months when I heat my garage workspace :>)

Our home was built in 1987 and no additional insulating has been done.

If you are getting similar comparisons from your energy providers, I wouldn't bother with increasing the insulation.

 

[Jerry1]

My home was built in 1956 and has very little insulation. Biggest issue I have is that I get ice dams in the winter. I got a few quotes (pre COVID) and to just put in extra insulation was about $3 to $4 grand. To actually seal the attic or spray foam the underside of the roof, was around $10K. Hard to say how much those prices have increased. The sealing or spraying the underside makes to most sense but as others have noted, there’s no way it will ever pay for itself in my lifetime. Especially my expected lifetime in this house of about ten more years.

The problem I have with just blowing in insulation is that it will bury all my mechanicals. My house is built on a slab so my electric and HVAC ductwork goes through the attic. I don’t really want to bury everything in a couple feet of cellulose. I’m thinking of just doing enough to get rid of the ice dams. Hopefully that could be accomplished by just bringing the cellulose up to the top of the rafters. Either way, I’d want to get a couple mechanical issues buttoned up first. I also like the idea of getting the big air gaps sealed.

The unfortunate thing is that my utility bills are not high enough to make this financially positive. I wish it weren’t that way. I don’t like to be wasteful but the reality is that it’s cheaper to just turn up the thermostat than it is to pay for insulation. Even the ice dams are really not a problem because I have very large overhangs all around my house.

 

[2HOTinPHX]

What does your electric/gas bill show? Our gas bill says we are below the average usage based on similar homes. The electricity bill says we are in the most efficient neighbors group, except for the winter months when I heat my garage workspace :>)

Our home was built in 1987 and no additional insulating has been done.

If you are getting similar comparisons from your energy providers, I wouldn't bother with increasing the insulation.

Unfortunately there's a lot of variation in our neighborhood. Single story and two stories, pool or no pool. We are only two people versus large families or singles. I work from home so we never really get to raise the temperature in the house to lower the use. We are usually average or slightly below..

 

[W2R]

My house has lots of insulation, which makes it very comfortable most of the time plus my energy bills are low for this area. Electric bill averages $95/month.

This is good because I am not getting any younger and from what I understand, old people suffer more than others from excess summertime heat.

I also have ceiling fans that I could turn on in the summer if I would just remember to do so!

 

[Sunset]

My home was built in 1956 and has very little insulation. Biggest issue I have is that I get ice dams in the winter. I got a few quotes (pre COVID) and to just put in extra insulation was about $3 to $4 grand. To actually seal the attic or spray foam the underside of the roof, was around $10K. Hard to say how much those prices have increased. The sealing or spraying the underside makes to most sense but as others have noted, there’s no way it will ever pay for itself in my lifetime. Especially my expected lifetime in this house of about ten more years.

The problem I have with just blowing in insulation is that it will bury all my mechanicals. My house is built on a slab so my electric and HVAC ductwork goes through the attic. I don’t really want to bury everything in a couple feet of cellulose. I’m thinking of just doing enough to get rid of the ice dams. Hopefully that could be accomplished by just bringing the cellulose up to the top of the rafters. Either way, I’d want to get a couple mechanical issues buttoned up first. I also like the idea of getting the big air gaps sealed.

The unfortunate thing is that my utility bills are not high enough to make this financially positive. I wish it weren’t that way. I don’t like to be wasteful but the reality is that it’s cheaper to just turn up the thermostat than it is to pay for insulation. Even the ice dams are really not a problem because I have very large overhangs all around my house.

Those quotes seem pretty high to me. I did a 1962 home, 2 story 2,000 foot, and it was ~$500->$600 about 20 yrs ago. So now I'd expect double.
They added thin plywood panels on the access hole, to go up 2 feet, so the blown in insulation would not fall out the access hole.

I don't see a problem covering your electric and HVAC ducts with cellulose, as those are rarely going to change and would probably make the HVAC work better as they must be losing a lot of heat in winter.
Now if you have your actual furnace or A/c in the attic, those would need to be fenced off.
You could take photos before the work, so that you know within a foot where the wires/ductwork run and just push the insulation to the side if work was needed.

 

[Happyras]

Fun Thread to read.....but as a licensed engineer, I am surprised people do not do the simple math. Here, let me help you with a calculator;
https://www.builditsolar.com/References/Calculators/HeatLoss/HeatLoss.htm
You can quickly see if it makes sense (typically not)

 

[Yoheadden]

We had blown in insulation done 2 years ago in our 2 story house built in 1982. It was a quarter of the price it would have been using rebates through the utility company.

 

[Jerry1]

I don't see a problem covering your electric and HVAC ducts with cellulose, as those are rarely going to change and would probably make the HVAC work better as they must be losing a lot of heat in winter.

I’m working through a problem. The HVAC ducts are now fine. I had them all replaced a couple years ago. Then I had an electrician repair some issues and he found a couple issues in the attic. One was very concerning. There was a junction box with no cover on it buried in the little bit of insulation I do have. He found it when he hit it with his foot and it buzzed. Not good. He cleaned that up and looked for more but I’m not convinced all is as well as I would like up in the attic. I also want to replace both of my bathroom fans.

I lost momentum this year because I got sick but I’m hoping I can get this done this coming year. Once I get things buttoned up, I don’t mind covering things, but I’m not sure I want a 2 foot covering over everything. Taking “before” pictures will certainly be a good idea. I was actually putting some stick in there as markers. Kind of like they do with fiberglass sticks to mark the driveway for the snowplow.

ETA: I got this in my inbox today from my gas company. Hard to believe this. Probably has more to do with the number of people in the household and not the shape of the dwelling.

Almost there! This month, you spent about $11 more than the most efficient households in your area.

 

[Yoheadden]

The company I used boxed off any openings(boxes) for bathroom fans, as well as the opening to the attic with a styrofoam board type product.

 

[2HOTinPHX]

Op here
Thanks for all the replies. Just thought I would share update. We had the two companies come out we talk to at the home show.
The first one we talked to gave us a ballpark of about 400.00 after 600.00 SRP rebate automatically applied. When they got here that price increased to $625.00. Only spent about 10 minutes total. Quick look in the attic. Advised the blow in fiberglass wrote down some notes. Advised about one week out. Didn't provide us with a written quote. So so sales job...not too impressed.
2nd guy seemed much more knowledgeable at the home show when we talked to him.. He did a basic scan of the ceiling with a infrared gun and showed where we were lacking insulation and around the recessed lighting. He was here for over 2 hours. Talked about a lot energy items such as our 50" 2008 Plasma TV hanging on the wall. Yeah it can put a little heat and sucks a little juice but we still love the picture. He talked about ceiling fan usage not always the optimum way to cool a room. Way too much detail for us to remember. Nice guy left a $25.00 gift card.... bribe... LOL? He recommended cellulose over the existing cellulose and bring it up to R43. He said it was better than fiber glass for a few reasons. Add weather stripping around and attach foam board insulation on attic access. Definitely a top notch "sales" job. Was ready to sign up till we get his written quote. 1831.00 less 600.00 SRP rebate so 1231.00 for insulation. Almost twice the first quote. I think I would feel more comfortable with this guy doing the work but not twice as comfortable. He did offer us advice on sealing the recessed lighting ourselves from inside the house and then quoted them doing the same 34 lights and exhaust fans at 570.00. Got some pretty tall vaulted ceilings so not sure I want to deal with it. Not sure at 570.00 how long it would take to recoup?
So 1800.00 total. Not too bad for everything I guess? I know we get the most bang for buck on insulation but feel like we would be quitting on the 10 yard line?
Might have to get another quote or two?

 

[Qs Laptop]

Op here
Thanks for all the replies. Just thought I would share update. We had the two companies come out we talk to at the home show.
The first one we talked to gave us a ballpark of about 400.00 after 600.00 SRP rebate automatically applied. When they got here that price increased to $625.00. Only spent about 10 minutes total. Quick look in the attic. Advised the blow in fiberglass wrote down some notes. Advised about one week out. Didn't provide us with a written quote. So so sales job...not too impressed.

And this guy said nothing about the leaks around recessed lighting and other openings into the attic?

2nd guy seemed much more knowledgeable at the home show when we talked to him.. He did a basic scan of the ceiling with a infrared gun and showed where we were lacking insulation and around the recessed lighting. He was here for over 2 hours. Talked about a lot energy items such as our 50" 2008 Plasma TV hanging on the wall. Yeah it can put a little heat and sucks a little juice but we still love the picture. He talked about ceiling fan usage not always the optimum way to cool a room. Way too much detail for us to remember. Nice guy left a $25.00 gift card.... bribe... LOL? He recommended cellulose over the existing cellulose and bring it up to R43. He said it was better than fiber glass for a few reasons. Add weather stripping around and attach foam board insulation on attic access. Definitely a top notch "sales" job. Was ready to sign up till we get his written quote. 1831.00 less 600.00 SRP rebate so 1231.00 for insulation. Almost twice the first quote. I think I would feel more comfortable with this guy doing the work but not twice as comfortable. He did offer us advice on sealing the recessed lighting ourselves from inside the house and then quoted them doing the same 34 lights and exhaust fans at 570.00. Got some pretty tall vaulted ceilings so not sure I want to deal with it. Not sure at 570.00 how long it would take to recoup?
So 1800.00 total. Not too bad for everything I guess? I know we get the most bang for buck on insulation but feel like we would be quitting on the 10 yard line?

Maybe it's not that critical in Arizona but here in Minnesota plugging the leaks into the attic from openings caused by lights, ceiling fans, etc. is critical. I would rather go that route first, then do the insulation install.

In fact, I'm looking to hire someone to do that for me. In your case, $570 seems a bit steep, but maybe not since you have 34 possible sites to consider. Will the insulator go up into your attic and seal these openings or will he do it from inside the living area? (Can he work up in the attic with vaulted ceilings?)

For comparison sake, back in early January 2020 I got two quotes to seal the air openings, weatherstrip and insulate the access door, replace bathroom fan exhaust tubes with insulated ducting, and blow in cellulose insulation to get to R-50. They were also going to install air chutes in every truss space, something I guess you won't need and would add to the cost.

Estimate 1 was $2,508
Estimate 2 was $2,239

Might have to get another quote or two?

Since the two quotes are wildly different I would want to get another quote. Be sure to include sealing the air leaks into the attic, if that is important in Arizona. If it is important you might want to get that quoted as a separate line item, like the quote for estimate #2.

 

[Qs Laptop]

Talked about a lot energy items such as our 50" 2008 Plasma TV hanging on the wall. Yeah it can put a little heat and sucks a little juice but we still love the picture.

...and since you brought it up. Sure, the plasma TV picture looks good to you. You're accustomed to it and it "looks good." But ask anyone with a 15 year old plasma that has gotten a new TV recently and they would never go back to plasma.

 

[ncbill]

...and since you brought it up. Sure, the plasma TV picture looks good to you. You're accustomed to it and it "looks good." But ask anyone with a 15 year old plasma that has gotten a new TV recently and they would never go back to plasma.

You'll get my 2011 Panasonic 50" plasma HDTV when you pry it from my cold, dead hands!

Going to OTA anyway & my Tivo only tunes ATSC 1.0...so 720p/1080i signals.

Perceiving 4K at the current distance my set sits would require shoe-horning in a 65" model.

 

[2HOTinPHX]

You'll get my 2011 Panasonic 50" plasma HDTV when you pry it from my cold, dead hands!

Going to OTA anyway & my Tivo only tunes ATSC 1.0...so 720p/1080i signals.

Perceiving 4K at the current distance my set sits would require shoe-horning in a 65" model.

LOL exactly how I feel...not turn this into a TV debate but using OTA connection and PBS Nature has some incredible close ups of fish recently and just mind blown images from where we sit. Microscopic jellyfish with even smaller fish hiding under it.

Still learning more about insulation....seems blown in more cellulose is preferred over blown in fiberglass?

 

[Qs Laptop]

You'll get my 2011 Panasonic 50" plasma HDTV when you pry it from my cold, dead hands!

https://www.avsforum.com/index.php?posts/62316163

 

[2HOTinPHX]

https://www.avsforum.com/index.php?posts/62316163

https://youtu.be/-X7WUxU4LDI

Nice video comparison...plasma still a great picture... [emoji106]

 

[ncbill]

https://www.avsforum.com/index.php?posts/62316163

Once it dies, sure, I'll buy an OLED set.

But at my viewing distance I'll have to upgrade to 65" to see 4K properly.

At least that's what I'll tell my wife.

Will then need to add a sound bar, maybe some wireless speakers for best "surround sound" experience...

 

[Happyras]

We had a fire, insurance bought me a new 83 inch OLED, love it. We had a 2012 Panasonic Plasma, great pic, but Service Master said the power supply would soon die due to the smoke. I gave it to my friends who had it about 2 weeks, then pop goes the weasel.

Not so impressed with the life of the power supply...now back to insulation.

Seal the leaks and be done. Do the heat loss calc I posted and wake up to the low payback of extra blow in versus sealing leaks.