Author Topic: Blowing Insulation Into My Walls, What Do I Need To Know?  (Read 220 times)

Jon Bon

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Blowing Insulation Into My Walls, What Do I Need To Know?
« on: December 05, 2018, 04:26:01 PM »
I intend to blow some cellulose into my walls and attic this weekend, let me know what worked, and what did NOT!


The House: Aluminum sided house with balloon framing (I think). I already flipped up a piece about 4 feet up, plan do do another one about 12 feet up. Did a test bore hole and found no insulation at all, but probably 2 layers cedar siding. No asbestos siding (yay!) and all old wiring has been replaced.

The Plan: Rent the big machine at the big box store and buy a bunch of cellulose. I plan to bore 2.5 inch holes every 16 on center. I will buy 10 feet of clear 1 and 1.5 inch piping to reduce down and fit into the hole. I will bore the holes at approximately 4 feet and 12 feet or so. I still have to buy the self feeding bit. I've worked with cellulose a few times but never done the sidewalls.

Has anyone done this? What issues did you run into and how did you overcome them? I watched a bunch of videos and it feels very much like a  DIY job.


misshathaway

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Re: Blowing Insulation Into My Walls, What Do I Need To Know?
« Reply #1 on: December 06, 2018, 06:01:15 AM »
I had it done 1 season ago. Made a huge difference in warmth.

Even with the workers taking precautions it came inside through the baseboard heaters and bulged out panelling slightly in one room. Worth it, but on a DIY I would do one hole and then come in and see if you have any coming inside. I was washing walls for weeks after mine.

lthenderson

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Re: Blowing Insulation Into My Walls, What Do I Need To Know?
« Reply #2 on: December 06, 2018, 06:46:18 AM »
2.5" holes seem quite big to me. I think I always used 1-1/8 or 1-1/4 inch holes so when I pushed the nozzle in the lower hole, it sealed up tight. Then I would plug the lower hole and go to the upper hole. But it may be the type of machine I was using and that was probably 20+ years ago so technology may have changed.

MrSal

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Re: Blowing Insulation Into My Walls, What Do I Need To Know?
« Reply #3 on: December 06, 2018, 06:46:24 AM »
I dont think the big box store blower has enough power to insulate walls. You need a specific pressure for that - I believe it's 3.7 psi inside the walls.

For the attic, it will work just fine. It makes a big difference indeed - I insulated my attic and recently my basement and it's been great. Last bill of heating was about 30$ including the customer charge. I estimate my highest bill this winter will be around 60-70$ at most. Central PA and high elevation, so it's cold here (6000 average HDD winter). We keep our temperature at 67-68F when home and 60 when going to bed and off when not in the house for long periods of time. So far, with outdoor temperatures in the 20's the house drops during long periods of time to around 60-61F.

We don't have southern exposure unfortunately, so no solar heating gains there. I estimate that if we had, we could go without heat for most part! The house is a 1958 1300 sq ft ranch house with basement.

Jon Bon

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Re: Blowing Insulation Into My Walls, What Do I Need To Know?
« Reply #4 on: December 06, 2018, 11:26:57 AM »
@MrSal

Probably a very good point. I doubt I would able to get the pack level that they get. I only might only do 1 or 2 sides of the house TBD, depends how easy it goes! Turns out I have at least an inch of wood of various types underneath my siding.

I was able to fit a 1 inch tube up the bay about 4 feet, so that will be good start. Ill rent the machine this weekend and report back.  Due to the thickness of the sheeting I had to angle my bore hole up.

@lthenderson

You can do a 1.5 inch hole with a 1 inch pipe, but you can only do that small section. The idea is to run a pipe all the way up or down the wall cavity so its is forcefully packing the cellulose in the length of the stud bay, rather then dumping it in one spot and just letting it settle over time.

bacchi

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Re: Blowing Insulation Into My Walls, What Do I Need To Know?
« Reply #5 on: December 06, 2018, 11:46:18 AM »
The rental at my big box is only 2.5psi. That's 40% less than the machines that the professionals use. Without the pressure, it won't really be "dense pack." It'll settle. You might do a wall and then check the level in a week and, if it's settled, add some more.

Or you could rent a professional blower at a local equipment rental store. The Intec blowers, like the Force/2, would do the job.

Jon Bon

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Re: Blowing Insulation Into My Walls, What Do I Need To Know?
« Reply #6 on: December 06, 2018, 12:12:00 PM »
@bacchi That's, that is a very good point. Im gonna go ahead and try it as doing my attic alone would be worth it. My neighbor and I are both going to use the machine and help each other out. So it should be a good weekend! Hopefully less pressure means less change of blowing out my interior walls? Always a silver lining!

Yeah if I could do the attic and 1.5 floors of my house that might be worth it, for a cost of maybe 200 bucks?