Attic ventilation and insulation - Page 3

cmittle · 11-19-08, 01:31 PM

When I was walking through Lowe's last night I saw what appeared to be one of these sitting in the insulation aisle. It would make sense for them to have one for rental.

toyobug · 11-22-08, 11:17 AM

sounds like a good deal. Something for me to check into.

TimJFowler · 12-04-08, 05:53 PM

Daox,

You and I are in the middle of the same project, just different houses. But, I found out that not all blow-in Cellulose insulation is the same. Google: 'cellulose insulation ammonium sulfate' and you'll see what the issue is. Unfortunately, Greenfiber cellulose insulation has ammonium sulfate as a treatment - http://greenfiber.com/_assets/PDFs/MS-6.4-043.pdf.

From what I have read and heard, a borate or boric-acid only cellulose insulation is the better product. Unfortunately, I haven't found anyone locally who will sell it to a homeowner.

FWIW,
Tim

Daox · 12-04-08, 08:32 PM

Thanks Tim, thats good to know. I'm actually planning on buying a different brand from a more local chain. I don't know the exact name, but I'll look into it. Its also way cheaper. Its currently on sale for $3.65 per bag (same size bag as GreenFiber).

Daox · 12-06-08, 04:06 PM

The saga continues. Today I picked up the cellulose, all 50 bags of it. It honestly took up a lot less room than I thought it would. I have it stacked in my garage atm while I get the attic prepped for blowing it in.

It turns out this stuff is made fairly locally, which explains the great price ($3.65 on sale and $3.99 normally vs Menards and Homedepot's $6.50 for GreenFiber).

Daox · 12-06-08, 06:32 PM

I'll also mention my cousin built a raised platform to retain at least some storage after the cellulose is blown in. It is large enough for about two 4x8 sheets of plywood. We're not planning on using it for much but decided now was a good time to do this instead of finding out we need it later.

My next step is going through the attic, putting the fiberglass insulation back down in areas. Right now I have two piles of fiberglass on each end of the attic that was placed randomly around the attic.

I also have to build a barrier and insulated cover for the attic access to minimize heat loss through the access. This will be made of polystyrene. I think I'm also gonna need to put something above the polyiso insulation as it may not be tall enough to hold back the cellulose after its all blown in. I'll probably just staple in some cardboard or something.

larryrose11 · 12-08-08, 08:32 PM

Daox,
Don't forgert to seal up all the wall headders and other penetrations with GreatStuff.

Also, I read a good article a bit back about reading a roof after it snows. Here is the link Home Energy Magazine Online
The web site is a treasure of information. Here is the front end of the site. Look for the DIY tab:
Home Energy Magazine Online

Higgy · 12-09-08, 03:34 PM

That's a great site Larry. I totally didn't know that. That makes me wonder big time, cause a lot of the homes around my place don't have a lot of snow on the roof, even in the winter. That scares me cause I'm wondering just how much heat I'm losing. I'm going to keep a watchful eye on that this winter. We have icicles coming off our roof usually in spring time only when the snow is melting off the roof and then we have a cold day the next day. That's the only time it happens but that should be normal right?

Thanks for that site.

Daox · 12-09-08, 03:55 PM

Thanks Larry. I have read that article before and its amazing how bad some houses are! I have gone through and sealed pretty much everything. I think there are two more fixture holes that I'll need to get at. Thankfully, all the wall headers are plastered over, so they are already sealed.

larryrose11 · 12-11-08, 07:08 AM

Higgy,
The only place we did have icicles on our house (before the complete exterior remodel ) were on the aluminum overhangs, no place else.

We used to get some snow melt at our eves, but the external remodel took care of that. This remodel , as far as the eves are concerned, included spray foam at external wall headers holding ventilation channels (0.5'' inch by 24'') in place in the eves, to about 5" thick. Being an efficiency nerd and having a very shallow 3:1 pitch roof, having ONLY 5 inch of cellulose (total R value of 3.5*5"=17.5) was not nearly enough. So, I made polly-iso foam blocks, 5"thick (R = 6.5*5'' = 32.5), 24" deep block to fit in between the studs, and packed the rest with cellulose. I calculated that the addition of the foam blocks reduces heat loss to the attic by 20%, which is why I went overboard.
More about this is back on the EcoModder site, Attic insulation - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com

12-04-08, 05:53 PM	#23
TimJFowler Apprentice EcoRenovator Join Date: Dec 2008 Location: Santa Fe, NM Posts: 184 Thanks: 9 Thanked 12 Times in 11 Posts	Daox, You and I are in the middle of the same project, just different houses. But, I found out that not all blow-in Cellulose insulation is the same. Google: 'cellulose insulation ammonium sulfate' and you'll see what the issue is. Unfortunately, Greenfiber cellulose insulation has ammonium sulfate as a treatment - http://greenfiber.com/_assets/PDFs/MS-6.4-043.pdf. From what I have read and heard, a borate or boric-acid only cellulose insulation is the better product. Unfortunately, I haven't found anyone locally who will sell it to a homeowner. FWIW, Tim __________________ - DIY Adventures in Applied Sustainability - To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

12-04-08, 08:32 PM	#24
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Thanks Tim, thats good to know. I'm actually planning on buying a different brand from a more local chain. I don't know the exact name, but I'll look into it. Its also way cheaper. Its currently on sale for $3.65 per bag (same size bag as GreenFiber). __________________ 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.

12-06-08, 04:06 PM	#25
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	The saga continues. Today I picked up the cellulose, all 50 bags of it. It honestly took up a lot less room than I thought it would. I have it stacked in my garage atm while I get the attic prepped for blowing it in. It turns out this stuff is made fairly locally, which explains the great price ($3.65 on sale and $3.99 normally vs Menards and Homedepot's $6.50 for GreenFiber). Attached Thumbnails __________________ 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. Last edited by Daox; 12-06-08 at 06:27 PM..

12-06-08, 06:32 PM	#26
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	I'll also mention my cousin built a raised platform to retain at least some storage after the cellulose is blown in. It is large enough for about two 4x8 sheets of plywood. We're not planning on using it for much but decided now was a good time to do this instead of finding out we need it later. My next step is going through the attic, putting the fiberglass insulation back down in areas. Right now I have two piles of fiberglass on each end of the attic that was placed randomly around the attic. I also have to build a barrier and insulated cover for the attic access to minimize heat loss through the access. This will be made of polystyrene. I think I'm also gonna need to put something above the polyiso insulation as it may not be tall enough to hold back the cellulose after its all blown in. I'll probably just staple in some cardboard or something. Attached Thumbnails __________________ 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.

12-09-08, 03:55 PM	#29
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	Thanks Larry. I have read that article before and its amazing how bad some houses are! I have gone through and sealed pretty much everything. I think there are two more fixture holes that I'll need to get at. Thankfully, all the wall headers are plastered over, so they are already sealed. __________________ 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.

11-19-08, 01:31 PM	#21
cmittle Helper EcoRenovator Join Date: Oct 2008 Location: Sioux Falls, SD Posts: 56 Thanks: 0 Thanked 1 Time in 1 Post	When I was walking through Lowe's last night I saw what appeared to be one of these sitting in the insulation aisle. It would make sense for them to have one for rental.

11-22-08, 11:17 AM	#22
toyobug avid DIY'r Join Date: Sep 2008 Location: MS. Gulf Coast Posts: 154 Thanks: 0 Thanked 1 Time in 1 Post	sounds like a good deal. Something for me to check into.

12-08-08, 08:32 PM	#27
larryrose11 Efficency nerd Join Date: Dec 2008 Location: S. E. Michigan Posts: 14 Thanks: 0 Thanked 0 Times in 0 Posts	Daox, Don't forgert to seal up all the wall headders and other penetrations with GreatStuff. Also, I read a good article a bit back about reading a roof after it snows. Here is the link Home Energy Magazine Online The web site is a treasure of information. Here is the front end of the site. Look for the DIY tab: Home Energy Magazine Online

12-09-08, 03:34 PM	#28
Higgy The Gardener Join Date: Oct 2008 Location: Manitoba - Canada Posts: 492 Thanks: 17 Thanked 8 Times in 7 Posts	That's a great site Larry. I totally didn't know that. That makes me wonder big time, cause a lot of the homes around my place don't have a lot of snow on the roof, even in the winter. That scares me cause I'm wondering just how much heat I'm losing. I'm going to keep a watchful eye on that this winter. We have icicles coming off our roof usually in spring time only when the snow is melting off the roof and then we have a cold day the next day. That's the only time it happens but that should be normal right? Thanks for that site.

12-11-08, 07:08 AM	#30
larryrose11 Efficency nerd Join Date: Dec 2008 Location: S. E. Michigan Posts: 14 Thanks: 0 Thanked 0 Times in 0 Posts	Higgy, The only place we did have icicles on our house (before the complete exterior remodel ) were on the aluminum overhangs, no place else. We used to get some snow melt at our eves, but the external remodel took care of that. This remodel , as far as the eves are concerned, included spray foam at external wall headers holding ventilation channels (0.5'' inch by 24'') in place in the eves, to about 5" thick. Being an efficiency nerd and having a very shallow 3:1 pitch roof, having ONLY 5 inch of cellulose (total R value of 3.55"=17.5) was not nearly enough. So, I made polly-iso foam blocks, 5"thick (R = 6.55'' = 32.5), 24" deep block to fit in between the studs, and packed the rest with cellulose. I calculated that the addition of the foam blocks reduces heat loss to the attic by 20%, which is why I went overboard. More about this is back on the EcoModder site, Attic insulation - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com