Blown-In Insulation in Existing Sheetrocked Walls

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  #1  
Old 07-20-09, 09:24 AM
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Blown-In Insulation in Existing Sheetrocked Walls

Hi,

I'd like to blow-in insulation in my 120 square foot attached mud room where it is very cold int the winter in NY. I believe the old homeowner put the addition on and did not insulate. Is there a way to cut holes in the sheetrock in the walls and ceiling, blow in the insulation, and then patch the holes? Or, would I be better off ripping out all of the rock, insulate with regualr fiberglass or mineral wool, and then re-sheetrock? Thanks

S
 
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  #2  
Old 07-20-09, 09:56 AM
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I did this to my 2 story house. Attic and walls and love this stuff.
I did it from the outside of the house which would be your best bet! What kind of siding do you have? Can you take a section off??

I have wood lap and I took nails out in the row I was going remove, drilled 1 7/8" holes in the sheathing, blew it in, plugged it w/ dowels and caulking, and put the siding piece back up.

You can do this from the inside, but its giong to make a mess!! The cellulose is extremely dusty and clings to everything. Make sure you leave the machine outside, and have a friend stuffing it full for ya and also so he can turn it on and off! Some of them come w/ a remote, but still you would have to make a bunch of trips in and out to refill it.

I wouldn't wanna tear all that drywall out and redrywall! That would be harsh, just to insulate. Unless you plan on gutting it for a remodel?

Hope this helps ya out!
Good Luck
Chris
 
  #3  
Old 08-18-09, 08:02 PM
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Thanks for the response. Quick follow-up; Can I also use the blown-in celluose insulation for the bays in the ceiling as well? The roof of my mudroom is flat. How do I hand le the light fixture in the ceiling when blowing in the insulation? Thx much
 
  #4  
Old 08-19-09, 09:04 AM
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Now, the ceiling thing, I don't know. You have to be carefull w/ vetilation!! So, the ceiling is in order like this: Sheetrock, joists, roof? I would think you could, but you might wanna wait til someone else answers. If you can do it, the light fixture, just leave it there. Its not going to hurt the wiring or anything! If you want maybe take it down and stuff some towels or something up there, b/c dust will come out of any kind of nook and cranny!!
Not sure if drilling a hole in each joist section is going to do it? The ins. won't spread out to much. Is there anyway you can get access to the joists and shove the hose down the whole way and fill up each section?? I did this in my attic. Worked out great. Extremely dusty during the procedure, but saved me money!
 
  #5  
Old 08-19-09, 01:58 PM
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HI,
I have done this type of insulation and it works really well. Is there any access to the attic space. I am assuming the roof has a pitch because you live in snow country. As small as the room is, you wouldn't have to walk around in the area you want to insulate. Just get located and the stuff would blow quite a way. You could always push it with something if it didn't blow far enough. The last time I did this I did about 1400 sq' and I used a blower from Lowe's. I bought the supplies from them so they didn't charge me fo the machine. If your in the attic you will want to have someone on the ground to bust up the bales of insulation and put them in the hopper. Saves a lot of ups and downs. The walls are different in that you can't get any easy access. If you have a sheet type siding I would come at it from the outside, if not, I would probably tear off the rock from the walls and put in batts of high density.Beer 4U2
Good luck.
D
 
  #6  
Old 08-19-09, 04:54 PM
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WOW, I wouldn't recommend tearing off the sheetrock!! That is crazy, and gonna cost you even more money just to insulate! I would recommend the drilling of the holes from the outside like I said in the first response. If you can't drill holes in your sheetrock, yeah its gonna be messy to fix it, but way better than re dry walling the whole room!!!
 
  #7  
Old 08-19-09, 08:04 PM
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There is no attic above this room and the roof has a slight pitch. Chris is correct - rock, joists, then roof. This mudroom is between my attached garage and sunroom. I may be able to access the joists from the garage side and jam the hose down to fill up each section as Chris has suggested. I will let you know how I make out. Thanks all for the help. S
 
  #8  
Old 08-20-09, 02:31 PM
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Only reason I kinda suspected this is b/c I have the same type mudroom, except that there is a room above w/ a pitched roof that has attic space. Also my joists run that direction from the garage to say your sun room. I didn't insulate mine though b/c I have a room above! I cut a small hole in the boards in the garage to access the joist space so I could run new wiring to the new lights that I hung in the mud room! Good LUck and keep us posted!
Chris
 
  #9  
Old 08-21-09, 05:09 PM
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The Plank guy is right about the sheetrock. If you can do it ant other way, do it. Like I said I would only do that if I couldn't access from the outside.
There is another option, depending on what type of siding you have.
The room you're wanting insulate has about 320 SQ' of wall space give or take for a door and windows and allowing that it is attached to one wall that is already insulated. If any of this isn't correct, I'm sure you can figure it out. If you have a type of siding that can be removed then re-installed you might consider using 4'x8' sheets of high density insulation board. I have built in Santa Fe, NM, and numerous places in Montana and we used this a lot. On a wall I would remove the siding, if you can, put furring strips from top to bottom on 24" centers, cut the insulation to fit in between the furring strips then re-install the siding. You're looking at 10 sheets of insulation, furring material and your own labor. This is probably the easiest way to fix the room. The material for the furring strips will depend on the thinkness of the insulation. If you were to use 1.5" insulation, use 2x2 for furring. If you use thicker than that, get wider material and rip it on a table saw to fit the thickness, this will save you money on the lineal footage. Most of all, have fun with it, any time you do little projects like this there is an opportunity to learn and to make a place more your own...
:USAF:
D
 
  #10  
Old 08-21-09, 08:03 PM
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Thanks Dan for presenting another option to consider. I have the original wooden cedar shakes on the house. They are a lot thicker than you get on the market today and in some spots there are at least two layers.
 
  #11  
Old 08-23-09, 02:40 PM
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Hi Dan and Plank,

I started preparing for my celluose insulation that I plan on blowing in this coming weekend. Drilled my 1 1/4 inch holes in every stud cavity (2 holes - one on top and one on bottom). Much to my surprise there is already existing faced fiberglass batt insulation in the walls. This mudroom gets so cold in the winter you wouldn't believe. I can hang meat in there. I thought for sure there was no insulation at all. Anyway, I'm even more perplexed as to how this room is getting so cold. I personally replaced the insulation under the floor in the crawlspace so I know that's good. I'm assuming that if the walls are insulated then the ceiling must be insulated as well. Why it's so cold I don't know - perhaps the existing fiberglass batts were installed incorrectly or it's cheap insulation - not sure. That said, here's my issue;

- Can I still blow-in celluose into the wall cavities even though there is existing fiberglass there? There is about a 1" - 1.5" gap between the rock and the fiberglass faced paper so I think I can get a decent amount of celluose in there between the rock and paper and fill any other voids there. Any problems that you can see with this approach? Am I ok going forward?

Thanks guys for your help.

S
 
  #12  
Old 08-23-09, 06:15 PM
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Not sure how much you will get in there w/ fiberglass already in there. Cellulose can get hung up easily on anything. You can try but it could be an expensive experiment. How much room do you have between the rock and paper?

Are you still gonna try to do the ceiling/roof? That may help also. Also, is there any kind of tyvek house wrap under your exterior siding? I am no expert, but cellulose is proven to do better than fiberglass. Maybe you have a lot of ventilation issues! ????

Well keep us posted on what you find out!
 
  #13  
Old 08-23-09, 08:45 PM
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Thanks Plank. I've got a good solid 1"+ between the rock and the paper. Realize its not much space but I'm going to try it and see how it plays out. Haven't tackled the holes in the ceiling yet - still pondering on how I'm going to attack it. The end of the day whatever celluose I do get into the wall cavities can't hurt in the long run. I'l let you know how it goes.

S
 
  #14  
Old 08-24-09, 08:04 PM
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what kind of light fixture?

Originally Posted by seanq View Post
How do I hand le the light fixture in the ceiling when blowing in the insulation?
What kind of light fixture do you have? If it is a traditional junction box with light fixture hanging down into the room, you shouldn't have to do anything. If it is a recessed light, you need to be careful. There are three main types: airtight, insulation contact (IC), non-insulation contact. If it is non-IC, you need to build a box or something to keep anything from touching the fixture.

Posting this question on the electrical/lighting forum will get you better answers from experts.
 
  #15  
Old 08-28-09, 09:23 PM
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Project Update

Thought I'd provide an update on the blow-in celluose project. Got around to doing it today with the machine rented from HD. Considering I have existing fiber already in the cavities I decide to drill three holes in each cavity, not two. Spoke with the manufacturer and they agreed on this approach. Glad I did as two would not have competely filled the cavity. Overall this wasn't too bad. Extremely messy as the insulation gets all over the place. Thanks averyone for the help. S
 
  #16  
Old 09-01-09, 09:37 AM
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Did you leave the machine outside while you blew it in? That was a huge mistake I made when I did my attic. I put the machine in the room that had the attic door. Didn't think the machine could blow all that insulation up the hose. But come to find out it would have!! Glad it all worked out for ya!!
 
  #17  
Old 09-01-09, 11:28 AM
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hey plank,

i had the machine in my garage because it was raining outside. man what a mess - even with a cloth underneath. glad i did it though. hopefully i see a difference when the winter rolls araound.

fc
 
  #18  
Old 09-01-09, 03:49 PM
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Did you see any vapor barriers ?

Insulation is ok, but in heat loss the big number usually is the infiltration loss... ie, a loose house brings in way too much cold air.

See if there is a vapor barrier anywhere, if not try a few coats of oil based paint and caulk the wall and ceiling joints.

Is there any heat source in the room ?
 
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Old 09-01-09, 06:00 PM
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Did not see any VB's. No, there is no heat source in the room whatsoever. Guess when the genius put the addition on he thought it wouldn't be necessary. Will take your suggestions and execute. THx

FC
 
  #20  
Old 09-02-09, 06:24 PM
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Sometimes people just want a 3 season room, or they intend on using it as a buffer zone.

With out a heat source all the insulation in the world will not keep it warm, just slow down the loss.

But once insulated well, you can leave a door open.
 
  #21  
Old 09-08-09, 03:57 PM
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Quick follow-up; would it be ok to use expansion foam spray ineach of the holes I drilled? I need to "top-off" each hole and to use the celluose to do that would take forever. Thx

FC
 
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