Adding more insulation

[KYFIRE]

Hi all, I'm looking at adding more insulatoin to my attic and wondering what other mustachians have done this and what was the result. 

It certainly looks lik I can use more blown in; only ~10-12" deep and poorly distributed, especially around the tray ceilings.  My dillema is that I know this is a possible DIY job but between twin toddlers, busy work schedule, and just all the other llife hassles I'm thinking it might be best to outsource this job.  It's ~2750 sqft and I would have to add all the eave vents as well.

My questions:

1.  Was it worth it?  Did you see a noticable change?  I know it will be better but want to have appropriate expectations.
2.  Did you do it yourself and was it worth the savings?  What was the PITA factor?
3.  How much ($/sqft) and R-Value change

Thanks for any feedback!

[Paper Chaser]

Your results will depend on a bunch of factors that are pretty unique to your situation. Your location, the design and orientation of your home, how well air sealed it is, the energy type powering your HVAC, the temp you set your thermostat to, etc will all impact the effectiveness. But it's not going to hurt, no matter what.

I will say, that I used to read lots of people (not necessarily here) claim that they had insulation jobs like that done by professionals for little or no more than what it would cost to DIY. That was pre-COVID, so who knows if that's still true but it's worth getting some quotes for comparison. Especially with how busy you seem.

Also, I'm going to include this map. Since you didn't mention your location (I'm assuming KY but who knows), you can use it to determine the R value that you might want to target:

[Sanitary Stache]

I am in a northern climate and my state has incentives for weatherization.  One of them is an energy audit.  If your State has a similar program, I highly recommend it.  They usually give you a break down of DIY vs professional costs.

I got a home inspection like report that described all the energy upgrades I could make in the 0-10 year time frame and their likely cost savings/payback periods.

Building Code here seems to be calling for R-49.  I think the weatherization team is looking for 23 inches of blown insulation in the attic and that is higher than R-49.  Reducing air leaks is a huge part of the weatherization also.

The people I eventually hired did the whole job (including full spray foam on basement walls) in a day.  They took out all the old insulation, built a "dam" at the attic access hatch, spray air sealed the whole attic and installed the eave vents, and blew in 30 inches of insulation.  The State incentives covered 50% of the work, so definitely cheaper than DIY.

I have blown in insulation in the past and it wasn't bad.  We took out all the old insulation, did the best we could for air sealing and then blew in new with a rented machine.  I wore all the PPE and it took about 2 days with two people.

[KYFIRE]

Thanks!

A couple of answers:

Yes, I'm in KY so I would fall into the zone 4 but I would probably aim to get closer to R49 (more is better right).  I'm all electric with a heat pump (full variable speed one so already highest efficiency). 

I'm looking at the incentives from my electric company as well as the federal government.  I need to confirm with the power company as insulation "may" be included up to $750.  What I did find interesting is that the federal program seems to be changing.  In the past I had a cap of $500, so when I got the new heat pump and high efficiency water heater I was capped, and that cap was a cumulative.  It looks like the new incentive, starting next year is $1,200/yr.  https://programs.dsireusa.org/system/program/detail/1274/residential-energy-efficiency-tax-credit

So it might be cheaper to wait til then (from a pure money standpoint)?

[Sanitary Stache]

The new legislation seems to provide more incentives, but it is going to take the States a while to get that money into programs.  I am moving forward with another energy audit from the low income weatherization providers that are still operating off last years funding allocations.  I figure I'll find more uses for the new money when it becomes available (I am looking for electric panel upgrade, whole house heat pump and eventually rooftop solar and a battery backup).

[getsorted]

I removed the old insulation from my attic last fall. That was essentially a very hot, dirty vacuuming job. Disposal was also a pain. I mainly did it because it was very old cellulose insulation and I was concerned about mold. It took two days and was physically very taxing (the industrial vac/blower I rented was heavy!). I did it myself because I couldn't find anyone who would do it.

I ended up having the new fiberglass insulation blown in professionally, because my utility company was paying for half of it. The cost to me was $325 and it took them half an hour (attic was only 600 square feet and tall enough to stand up in). It was noticeably warmer in the house all winter despite using less gas, but because of price increases, didn't actually see any "savings."

[Sibley]

I'm in zone 5. I have an old house that does not have any insulation in the walls, but it did have a little bit in the attic. Doing attic insulation was not something I was comfortable DIYing, so I hired a company. They airsealed around penetrations and the top of the exterior wall, and added 18 inches of blown in cellulous, which got me up to R-50 if I remember correctly. It cost about $1200 I think, and I got a little back on a tax credit.  Maybe 20x 40 ft or so? I don't really remember the size of the house.

Yes, it was noticeable. I had the work done in the summer and when I came home from work the upstairs was noticeably cooler than it had been the previous day at the same time. My utility usage went down a little bit, but the biggest change for me was the overall comfort level. I actually had to adjust winter blankets because it wasn't getting as cold overnight, even in the coldest weather, so I was overheating. Between the attic insulation and replacing the black roof with a lighter gray roof, the upstairs has dropped about 10 degrees on the 2nd floor on hot summer days, and warmed up about 5 degrees on cold winter nights, independent of HVAC. I also haven't had any problems with ice dams since insulating.

Note - if you have an old house and do not have a vapor barrier on the exterior, you can not simply blow in insulation. You'll end up with a mold problem. You can insulate, but its harder and usually involves opening walls.

[Abe]

We have a similar size attic and had a company blow in fiberglass (I think, it's very fluffy) to increase it from around R-28 to around R-40. It cost ~$1000 before the tax credit. Our bedrooms were 2-3 degrees cooler afterwards. Interestingly, the house will stay less than 82 even with outside max temperatures 95-100. AC usage was minimal (turned on only a handful of times per day). This house has 2x6 studs, but no special additional wall insulation. I'd say it's worth it. 

[uniwelder]

I have had a company install, as well as do it myself, various occasions 3-14 years ago, and it cost the same for them to do it compared to me just buying material, except this last time.  The last house we bought 9 months ago, was quoted 1.5x more for a professional.  I ended up buying bags of cellulose and doing it myself, along with my wife or helper to feed the bags through.  Cost for the most recent house was about $.60/sq ft for enough material (plus $100 to the guy helping) to add R-30, and use of the machine was free.  Professional quote was $1/sq ft for R-30 added.

DIY was a bit of a pain in the ass and not worth it.  Attic area was 1,500 sq ft and a simple gable roof I could stand in at the center.  It took 2 trips with my full size truck (should have borrowed a trailer) to get the insulation, time loading and tying it down, about 10 bags before getting the hang of the machine, rewiring to bypass the thermal overload because it would shut down after 20 seconds empty, plus time for the actual blowing, then returning the machine.  I think I probably spent 16 hours total, plus 8 hours of helper time, for a savings of about $400 or so.  A professional would have had it done in an hour. 

Something I didn't factor into my original calculation was that I didn't get nearly the amount of volume as the bag of cellulose states.  I think a big part of that was me settling the material toward the eaves with a long stick.  The blower hose didn't have a lot of power, and I wanted to be sure the insulation went all the way over, so I waved a long stick through it at intervals during the blowing process of the outer perimeter.  Also, the cellulose, which is more dense than fiberglass, was being put over existing blown fiberglass, so I compressed it significantly.  This all caused me to buy about 30% more insulation that I planned, reducing my DIY savings. 

All four of my houses were lacking insulation, varying from around R-10 to R-19, so I added R-30 on top of everything.  It was definitely noticeable, particularly since the insulation value went up 2.5-4x.  In OP's case, there will be diminishing returns.  It sounds like the attic is already around R-30 to R-38, so getting to the desired R-49 is only a 30% increase.  However, if the attic doesn't have eave vents, OP would probably get the best return adding those and just having more air ventilation for the summertime, and then while someone is up there, spread the existing insulation around more evenly.  What kind of venting is already there?  If you add vents to the eaves, there should also be venting along the ridge.

The guy that added the extra blown cellulose to my first house, turned on the water spray slightly while blowing.  It didn't feel wet as it was being applied, and the material was still light and fluffy, but it certainly helped contain nearly all the dust that is notorious with cellulose.  I have asked others in the houses that followed, but everyone else said it wasn't how they did it.

I'm curious how people are ending up with such huge houses.  2,750 sq ft of attic space is enormous.  Is this a single level home?  If you want to cut down on energy usage, the best thing is to live in a smaller house.

[dot]

I'm in Zone 3, and this spring paid someone to boost our insulation from about R10 (a couple sparse inches of original rock wool from 1962) to R49 (blown in fiberglass). The cost was $1.1/sqft for the insulation over the house and slightly less for R29 over the garage. The cost difference between DIY and paying someone else to be in the attic when it was 90 degrees out was not enough for me to get itchy and sweaty, so we hired it out. Also while they were up there, they fixed damage and poor sealing of vents that we hadn't noticed. We hired a small local company. I DIY pretty much everything, but zero regrets at not going DIY for this. Total cost for a 1500 sqft house + 500 sqft garage was about $3k, including removal of some squirrel nests and general attic debris, and insulating and sealing the HVAC closet.

As far as cost savings, it's hard to come up with hard numbers, because this summer we had a record number of days over 100°F and entire weeks of 110° highs, while the other two summers in this house were much more mild. We're using only slightly more electricity to keep the house cooler than we did in previous years.

From a pure numbers perspective, it might not yet be a win for a few years, but from a comfort standpoint I am so pleased with this decision. The house just stays cooler longer, and it's so much more consistent and comfortable. There aren't any weird hot spots in rooms. We have original single paned aluminum windows and minimal insulation in the walls, and the attic insulation still makes a noticeable difference.

I'm excited to see how winter goes, because we have propane heat, and used $900 in gas last winter to keep the house at 65°. I think that may be the season where we start to see some bigger cost savings, but I'm also looking forward to staying warm at night.

[KYFIRE]

Thanks all for the feedback.

@dot, thanks for the $/sqft. 

It definitely seems like outsourcing is probably best bet given the PITA factor and current obligations (though I'm still waiting on quotes). 

I certainly am not expecting a fast ROI but the comfort improvements will be nice.

Thanks again.

[Uturn]

My last house was in zone 3 and I had soffit baffles installed and blown fiberglass to 22 inches. I don't recall the cost, but I wasn't shocked by it. It definitely increased comfort level and the AC ran much less.

My current house is zone 4 and last month I had baffles and blown fiberglass to 18 inches. I can tell a comfort level improvement and the AC runs less.  It was $1400 for a 1900 sq ft house.

Both houses had insulation before, but not much.

I helped a friend DIY his house once, and that is why I hired mine out.  It's not hard, but it is hot and messy.  Blown in takes two people, one to fill the hopper and one to spray.

[Jon Bon]

Thanks all for the feedback.

@dot, thanks for the $/sqft. 

It definitely seems like outsourcing is probably best bet given the PITA factor and current obligations (though I'm still waiting on quotes). 

I certainly am not expecting a fast ROI but the comfort improvements will be nice.

Thanks again.

Adding insulation to you attic is easily one of the best choices you can make to make your house more efficient as well as provide the most cost efficient improvements.

Generally the old insulation does not need to be removed. If it was doing its job before, so  adding more on top will be fine. Mold should not be an issue in an attic. If you have mold in your attic, you have a leak in your roof. Not to mention your attic is air sealed from the rest of your house. So again throwing insulation on top of existing would be fine. Vapor barriers in general are also not required.

I've rented the blower machine probably 6-8 times? it is a 2 person job but it is not difficult in any way, if anything its just dirty. Its only a PITA if you cant move around, the tube itself will blow it a good 8-10 feet out. The spreading itself is super easy, positioning the machine can be tricky as its heavy.

I don't notice a ton of difference in comfort, I mean I set my heat at 70, the house is at 70. So the difference is how often the heat itself runs of course. Get a quote if you want, but also price out how much it would cost you to buy all the mateirals at lowes and DIY. With how much contractors want to do anything I would assume this would be huge savings to DIY.

Why do you think you need more attic venting? Unless you are of course planning to cover up your existing attic vents.

[KYFIRE]

The ventilation I was talking about was the little foam inserts between the rafters that keeps some air flow to eaves.  If blow too much insulation it covers the eaves.  At least that's what I've seen recommended.

[secondcor521]

I DIY'ed from about R-30 to about R-60 in Boise, Idaho about two years ago.

Cost was $932.02.  I bought enough fiberglass insulation bales from the nearby Lowe's that they gave me a discount on the insulation and let me borrow the blower unit for free.  A friend of mine let me use his truck, he and his wife loaded the machine while I was in the attic running the end of the hose.  We mostly did my house but we also went to their house and topped off his insulation as well.

We both just added on top of the existing insulation, which in my house's case wasn't very even.  I enjoyed evening it out.

I did not follow the recommendations I received here to fill cracks and gaps.  I tried, but the existing insulation made it difficult to see, and the first several places I checked had not cracks or gaps.

On my 2020 tax return, I claimed $932 on line 19a of Form 5695.  This ended up resulting in a $93 federal tax credit.

It was a warm job, but one of the things we did that I thought worked well was to do the job in late October when the outside air temperatures had cooled off.

The whole thing - picking up the bales and blower, doing my house, doing his house, and returning the extra bales to Lowe's for a refund - took about 12 hours.

I thought the job was actually pretty fun and enjoyable and rewarding.  It did take time, though - the blower can only blow a certain amount of volume per unit of time.

My heating and A/C clearly cycle on and off less often, and the house is more evenly comfortable.  I don't think I saw very much in dollar savings; I think we used the extra margin to just maintain things at a more comfortable temperature - so same amount of spending, but more comfort.

The other thing insulation-wise that I have done that I thought was helpful was to put in the little styrofoam electric outlet insulators on all the electric outlets in the house which were on exterior walls, and to re-caulk around the windows.