DIY dense pack cellulose - Page 2

S-F · 08-24-11, 10:00 AM

Get a pressure tester so you can verify for yourself that it can push out 3.5 Lbs. Make a test box. Build a 16" O.C. box out of 2x4's. Cover the back with OSB or something and mesh off the front. Make it tall enough to give you a sense of how filling it all up works. I'll be easier to tear the cellulose out of a bad test box than an entire cavity.

hamsterpower · 09-09-11, 09:10 AM

I just did this last weekend in my kitchen project. I'm not sure if my job is up to dense pack standards, but with my open hand, I can not push into the cellulose at a test hole. I think it worked very well.

Here's what I did.

I rented the basic machine from Lowes. Set the adjustable plate at the output to about 25% open. Bought a 1 7/8" diameter universal vacuum hose and taped the included adapter to the end of the long 3" diameter hose that came with the blower. Then I pulled the hard adapter out of the flexible vacuum hose at the very end. This was so it would flex enough to pull out of the wall while blowing.

I used a 3" hole saw to drill a single hole at a time in the inside of the wall to be insulated. I did not want cellulose to blow out empty holes nearby. I drilled these holes about 6 foot high as the vacuum hose was 6 foot long.

The thin vacuum hose slid down the wall easily and I wrapped a towel around the hose to seal the hole. with the machine running I could hear when it bogged down. When this happened I pulled a few inches of hose out of the wall. When the hose got close to the hole I quickly turned it and pushed it up into the top of the wall, two feet above.

I did drill a few test holes to check the results and as I said above. I could not push my open hand into the cellulose.

To finish up I sprayed "Great Stuff" foam in the holes and pushed the plugs from the hole saw back in. As the foam cured I adjusted the plugs to be flush with the wall surface.

A note on prior steps: I had these walls open the week before and sealed everything with 2 -3" of spray foam from "Tiger Foam". I also made sure there were no barriers to keep the cellulose from filling the cavity.

The end results, I estimate an R-value of 39.5 where at best I had R16 before, and nearly a complete air seal.

Daox · 09-09-11, 10:04 AM

How thick are your walls?

S-F · 09-09-11, 11:14 AM

I was at Lowes the other day and saw their cellulose machine sitting out and I don't have the slightest bit of faith that it would be able to achieve a dense pack that wouldn't settle or wouldn't leave big holes. I think that calling rental centers to find a Force 1 or 2 would be what you'd have to do.

hamsterpower · 09-10-11, 06:46 AM

Quote:

Originally Posted by Daox

How thick are your walls?

They were 2x4, now they double 2x4 with a small gap between = 7.25".

| 3.5' | .25"gap | 3.5" |

hamsterpower · 09-10-11, 06:51 AM

Quote:

Originally Posted by S-F

I was at Lowes the other day and saw their cellulose machine sitting out and I don't have the slightest bit of faith that it would be able to achieve a dense pack that wouldn't settle or wouldn't leave big holes. I think that calling rental centers to find a Force 1 or 2 would be what you'd have to do.

The key was setting the adjustable plate at the output to 25% open. This way the full volume of the blower air was pushing a small volume of cellulose. I am confident that it is packed enough to never sag. Maybe not up to dense pack standards, but it won't sag. That was my goal.

S-F · 09-10-11, 09:35 AM

Quote:

Originally Posted by hamsterpower

The key was setting the adjustable plate at the output to 25% open. This way the full volume of the blower air was pushing a small volume of cellulose. I am confident that it is packed enough to never sag. Maybe not up to dense pack standards, but it won't sag. That was my goal.

You have to do the same thing with a brand new Force 2. If the blower can't put out 3.5 lbs at the hose you can't get a dense pack.

09-09-11, 10:04 AM	#13
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	How thick are your walls? __________________ Current project - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts. & To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

08-24-11, 10:00 AM	#11
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	Get a pressure tester so you can verify for yourself that it can push out 3.5 Lbs. Make a test box. Build a 16" O.C. box out of 2x4's. Cover the back with OSB or something and mesh off the front. Make it tall enough to give you a sense of how filling it all up works. I'll be easier to tear the cellulose out of a bad test box than an entire cavity.

09-09-11, 09:10 AM	#12
hamsterpower Apprentice EcoRenovator Join Date: Oct 2009 Posts: 142 Thanks: 0 Thanked 11 Times in 11 Posts	I just did this last weekend in my kitchen project. I'm not sure if my job is up to dense pack standards, but with my open hand, I can not push into the cellulose at a test hole. I think it worked very well. Here's what I did. I rented the basic machine from Lowes. Set the adjustable plate at the output to about 25% open. Bought a 1 7/8" diameter universal vacuum hose and taped the included adapter to the end of the long 3" diameter hose that came with the blower. Then I pulled the hard adapter out of the flexible vacuum hose at the very end. This was so it would flex enough to pull out of the wall while blowing. I used a 3" hole saw to drill a single hole at a time in the inside of the wall to be insulated. I did not want cellulose to blow out empty holes nearby. I drilled these holes about 6 foot high as the vacuum hose was 6 foot long. The thin vacuum hose slid down the wall easily and I wrapped a towel around the hose to seal the hole. with the machine running I could hear when it bogged down. When this happened I pulled a few inches of hose out of the wall. When the hose got close to the hole I quickly turned it and pushed it up into the top of the wall, two feet above. I did drill a few test holes to check the results and as I said above. I could not push my open hand into the cellulose. To finish up I sprayed "Great Stuff" foam in the holes and pushed the plugs from the hole saw back in. As the foam cured I adjusted the plugs to be flush with the wall surface. A note on prior steps: I had these walls open the week before and sealed everything with 2 -3" of spray foam from "Tiger Foam". I also made sure there were no barriers to keep the cellulose from filling the cavity. The end results, I estimate an R-value of 39.5 where at best I had R16 before, and nearly a complete air seal.

09-09-11, 11:14 AM	#14
S-F You Ain't Me Join Date: Nov 2009 Location: Northampton MA Posts: 662 Thanks: 6 Thanked 71 Times in 58 Posts	I was at Lowes the other day and saw their cellulose machine sitting out and I don't have the slightest bit of faith that it would be able to achieve a dense pack that wouldn't settle or wouldn't leave big holes. I think that calling rental centers to find a Force 1 or 2 would be what you'd have to do.