Too Much blown insulation issue in attic

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  #1  
Old 09-09-09, 06:07 AM
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Question Too Much blown insulation issue in attic

I recently found that I have mildew/mold (not dangerous type yet) in attic, and the inspector showed me why. The previous owners had too much insulation blown in. It's the type that looks like cotton pieces. There is approx 8-12" thick covering the main portion of the attic, while it's even deeper at the outer edges, where the soffit vents are. There is no airflow, and need to remove a large chunk of it. I even tried using a leaf blower from outside, to see if I could get it to move, but nothing. Besides using a shop vac, are there any other options?
 
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  #2  
Old 09-09-09, 06:28 AM
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I don't think it is an issue of too much insulation, it is more an issue of "in the wrong place" or possible air leakage that should have been sealed before installation.

Here are the problems. If the insulation was blown into the eves where it blocks air flow up through the soffit vents, that is bad and you would need to remove enough to open an air gap of one to two inches below the roof sheathing. The other issue is warm moist air from inside your home leaking up through that insulation. When it hits the cooler temps in the attic it would deposit some moisture/water and promote the growth of mold.

In Chicago you actually need all of that insulation and perhaps even more. I would suggest an energy auditor with a blower door and infrared camera to pressurize the home on a cool/cold evening and then take a look in the attic with the infrared camera. Any warm air leaking up through the insulation will shine like a light bulb.

As for the insulation, create a long handle rake so you can reach out to the eves and pull some of that insulation back. You don't have to remove it, just open up those vents.

Long distance trouble shooting is difficult so if you want more specifics, try to post some pictures. Photobucket.com and paste the link under the tab above.

Bud
 
  #3  
Old 09-09-09, 07:23 AM
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Thanks for the info. Another thought came to mind. Would it be wise to try and remove/relocate the insulation at the soffit area, by removing the outer siding edge (the vertical part above the soffits - fascia board?), and getting to the insulation from there? Or is that something that once removed, now will start a domino effect, and I'll have to replace all of the soffit/covers?
 
  #4  
Old 09-09-09, 08:07 AM
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The facia board is tucked under the drip edge and shingles so could be hard to get out and in. Ice and water shield, flashing and gutters if present add to the problems. Depending upon your soffit construction, you may want to replace that with some additional venting. Most homes never have enough. Here is some more reading.

ESB: Research Exposes Attic Ventilation Myth

You will want to open all of the rafter bays, not just those with venting below. I once built a "T" on the end of a long pole and installed some nails facing back towards me at an angle. That allowed me to push it in above the insulation and rack some of it back out. Of course, if the blown-in insulation has completely filled the soffit area, you have a job ahead of you.

Bud
 
  #5  
Old 09-09-09, 09:22 AM
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Thank-you very much for your help. I think that going through the fascia will be the best way of trying to tackle this. (Maybe not the easiest, but I'm not known for doing it that way). I'll try pushing it back in, first, to make sure that I don't have to then add more in later. Talked with a contractor, and they want $2500-3000 to remove all of it, so that's not going to happen. Again - thanks.
 
  #6  
Old 09-09-09, 09:32 AM
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There are baffles, if you can slide them up in there, that will maintain the one inch clearance for now and protect you if additional insulation is blown in later. If you can add an additional baffle over the end of the insulation to prevent wind washing, where vented air blows up through the first few feet of insulation, that would help. Like you need more to do.

Bud
 
  #7  
Old 09-13-09, 10:27 PM
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Dave, interesting discussion!

Originally Posted by Dave_H6381 View Post
Thank-you very much for your help. I think that going through the fascia will be the best way of trying to tackle this. (Maybe not the easiest, but I'm not known for doing it that way). I'll try pushing it back in, first, to make sure that I don't have to then add more in later. Talked with a contractor, and they want $2500-3000 to remove all of it, so that's not going to happen. Again - thanks.
and it inspires me to inquire, how does this contractor
propose to get the insulation out? a giant vacuum cleaner?
I'm in phoenix, obviously a different climate with different
issues. my house has this really old style insulation. it is
not fiberglass. more like some sort of cellulose looking stuff.
it was allegedly 'fireproof' when the house was new. I know
this cause my dad was the next door neighbor when he was
alive and said this stuff was garbage. he grabbed a handful and showed
me what happens if you light a match to it.
poof! apparently it was 'fireproof' like Christmas trees are
fireproof. for awhile, till the stuff wears off that made it
'fireproof'. these houses are 40 years old. it AINT fireproof!
it's also a silly mess. too much of it and I cannot get to
wiring and plumbing that need maintainence.

what sort of contractor did you contact? 2500 bucks is a lot.
don't blame ya for not doing it. but I may need to. was this
a contractor who also will blow IN NEW insulation after they
get the old mess out? I don't know where to look in the
yellow pages

thanks!
 
  #8  
Old 09-14-09, 07:33 PM
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Actually, that's what I use. For a small area, I use the old electric blower/vac with the vac attachment bag unzipped and an extra 10' length of 4" light-weight pipe attached. For bigger jobs I used a Harbor Freight $79 rolling shop sawdust collection blower I mickeyed to stand-up garbage bags with the cloth bag mounted above. Need a person below to compress the fluffy stuff, after turning off. Person in attic has some of the 50' hose connected to machine below. Do NOT use this around the flammable insulation. Be safe, Gary
 
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Old 09-19-09, 01:19 PM
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The orginal option from the contractor was to use 2 guys, 2-3 days @ 8 hrs each and $60/per guy. They were going to bag and remove it that way. He then proposed using a 'air vent cleaning truck' and basically do a reverse blow in. Still would take a day, but would cost the same, due to rental from his sub-contractor (go figure - the same cost).

I have since attempted to do a partial removal of the fascia board, and just like Bud had said, it started to look like it had too many problems with the flashing/gutters. So it's back to the original way, of going up with a small plastic rake and removing it from the vented areas (I'm assuming that all of the vents have the small baffles). Once I get that done, will then replace the baffles with the larger ones. It will be slow go, but will still be way cheaper in the end.
 
  #10  
Old 09-29-09, 02:37 PM
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After waiting until the attic cooled down (now only mid 70's up there), have more questions. Pulled some of the insulation away from the soffit area, and discovered that not only did it finally get some sunlight through, but there is also the normal yellow insulation coming up from below (BAT insulation?). So some of the soffit area appears to be blocked by that as well. Also, on a different location, after raking away the blown insulation and turning off the lights, there still was no daylight getting through the baffle.

When insulation is blown in, is it normal to see the wall insulation from below? Or should I end up cutting some of that out?

Between the joists (that have the soffit vents), do I really need to have baffles installed, or are they there JUST to provide some sort of airway path?
 
  #11  
Old 09-29-09, 02:57 PM
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Hi Dave, how old is the home? An old style of construction is called balloon construction where the wall cavities run from the basement to the attic and thus you would see the insulation from top or bottom.
Here are a couple of pictures: http://www.firefighterclosecalls.com...nstruction.pdf

If you have balloon construction, there are a few more steps you should take.

Bud
 
  #12  
Old 09-30-09, 07:17 AM
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This house was only built in 1991, so I doubt it was built using the 'balloon style' construction. So far, most of the joists that we have cleared has some if not all of the area blocked by the BAT, though. (Personally I think the type of construction is just called 'cheap and crummy' - have had other issues, and none have been good to clean-up).

I wouldn't think it would matter if some of the rooms are over also over the garage. Can I just cut it away (level with the drywall), and then just put up the baffles (if really needed)?
 
  #13  
Old 09-30-09, 07:36 AM
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Yes, sounds correct. I didn't think it was an old house. Keep as much as possible over the ceiling and top plate right up to the baffles. I just visited one of the first homes I built and was pleased at the compliments at how well it has held up. No leaks, cracks, shifting, or sagging. Nice to know the details pay off in the long run.

Maybe my fussy nature is why new home owners don't like to take me along when shopping for a house, they get discouraged at all of the problems I find. If they would only stop and think.

Anyway, you are headed in the right direction.

Bud
 
  #14  
Old 10-12-09, 06:04 AM
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Verified that I had a top sill on walls to attic. Assuming that the original homeowner did insulation job, as each and every joist had the BAT insulation stuffed at the soffit end, and then had blown insulation to the roof line (N-S sides of house - also the long ends of house). On E-W sides, they had stuffed the BAT at the soffit end, then really packed the blown insulation for the next 2-3 feet, and then put up more of the BAT (w/paper) and stapled that to the rafters.

Have opened up somewhere between 15-20 joists completely of the insulation, and can really tell a difference. Only the E side didn't get any openings, as the conduits as well as the joists running the same way, made it a balancing act. Will be getting a new roof put on next spring/summer, so can open those up then. This job is completed. Thanks for your help.

Two more questions though:

1) What is the best way to insulate the house fan (a cover? or placing BAT in the openings? or both? or other?)

2) When getting the new roof, do the roofers install the new baffles? Or do I need to get in to do it myself?

Just wondering...
 
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