I hope this part one and part two series doesn’t annoy people, but I hope it helps sort the two subjects, which coinside. <!—-><!—-><!—->
I live in a 2300 sq/ft side hall Colonial in New Jersey built in the 60’s, and plan to be here for a while, so I plan to spend some time and money now to save it in the future. Part 2 is dealing with the “Insulation” of my house.
II’m not sure of the quality of our insulation on exterior walls, but am not impressed with the Attic insulation. Half of the attic has craft faced between the 2×6 joists, and the other half of the house has what appears to be little styrofoam balls, the size of BB’s. I have never seen it before, and am not comfortable having it. But that is more of Part 1’s topic.
My issue is the exterior walls. I’m a hardcore DIY’er and will take on anything, given the proper knowlege base.
Can you blow cellulose insulation into a cavity with fiberglass? Opening up a small 3-4″ hole in each bay from the inside is no problem since i will be remodeling each room one by one and adding Crown. What other options do I have? I really want to stay away from spray foam due to cost.
Replies
AFAIK, your only option is to live with what you have, or strip the walls, pull it out and re-do it from scratch. I don't think you can blow cells or foam into a cavity with existing batts.
Mike Hennessy
Pittsburgh, PA
If you are going to live there for a while and spend some time and money why not strip the walls and foam the cavities?
There are some foam companies specializing in foaming existing framing. They drill various holes and inject the foam in a number of levels in the cavity. The pressure compresses the batt insulation somewhat. The process defiantly air seals the framing. I would get an energy audit before going down this path first to see if you have a curable situation.
Cool.
I didn't know it was possible to foam like that.
I'll have to find someone in the Atlanta area.
I had it done to my house. Two contractors in the Cincinnati area do it. The reason I suggested having an energy audit before having it done was even though the workmen were conscientious doing their jobs I could see not much material was going in. My insulation was pretty good and I really did not need it done. An audit might point to just some areas where it would be beneficial and you might not have to do the whole house.
agewon.... is that an old Narragansett indian name ?
i'd try one room... rent a blower...drill your holes ....say one 16" from the floor, one 16" from the ceiling
set the air control valve to almost wide open... so you are blowing a lot more air than cellulose
assuming these are batt fiberglass, it will have some cohesion... AND if it is kraft faced, even better, get the nozzle between the facing and the wallboard
as the cells blow in they will compress the fiberglass and create additional paths for the cells... it almost flows like water.... or a syrup..
see if you think you are blowing to the center of the bay... then move to the top hole.. if you really want to improve your blow... bore a center hole also.... go bottom, top, middle .... in every bay
keep an accurate bag count... the bags are all stamped with the weight per bag ( bale ) when you've blown one wall... figure out how many bays you did
subtract the studs and that will give you the area.... your weight tally will allow you to calculate how may pounds per sf you actually got
based on that you can make a determination if it's worth your while to keep going
my guess is... yes... unless your time is valuable... it will cost you the rental, some cellulose and some patching... but it should make a difference
whadda ya think ?
Edited 3/5/2009 5:06 pm ET by MikeSmith
Agewon derives from my nickname, Adrian=Age, and Won is because when people asked " Who won the pool game", the response was "Age won".
I think your plan is very reasonable and plan to try it after a few more questions. I am currently doing my daughters room and as of now, have had to patch lots of holes and nail-popping, so what the heck right?
What do you recommend as the media? Cellulose or fiberglass? My local box store is pushing blown fiberglass, and i am worried about my exterior passing too much moisture.
What are the recommended lbs/ft per bay? I undersrtand your formula, however dont know if a bay has better R-Value with cellulose, or batts. In otherwords, if compressing batts reduces the R-value, will blowing in the cellulose compress the batts to the point of negating their R-Value, but the compressed batting take up enough volume to negate the supposed R-Value of the blown insulation? WOW, my head just spun!
age
<<<<<What are the recommended lbs/ft per bay? I undersrtand your formula, however dont know if a bay has better R-Value with cellulose, or batts. In otherwords, if compressing batts reduces the R-value, will blowing in the cellulose compress the batts to the point of negating their R-Value, but the compressed batting take up enough volume to negate the supposed R-Value of the blown insulation>>>>
you just changed your goal and the target... your original question was " is it worth doing ?"
1st... fiberglass is bad insulation
2d what you have is inadequate
your choice
leave the plaster and blow thru holes....or....
take the plaster off and start over
the fiberglass is useless... or next to useless.... exchanging the volume occupied by the useless fiberglass with dens-pak cells will improve the insulation in the wall
after you do one wall, you can make a subjective judgement as to wether you think you improved it and was it worth the effort
your choiceMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
Mike,
you just changed your goal and the target... your original question was " is it worth doing ?"
You're ablosultly right :) I guess i should have said that i really liked your approach. However, not that I am questioning you experience or your method, but questioning my own preconceived notions of insulation.
I guess what you are saying is that even though you wont be getting as much "volume" of cellulose in the wall with the batting, it's still better than what I have, which is my goal. I plan to do as you said and try one room, and see the cost/benefit.
I also think that an energy audit at this time is useless for me. since I still have several windows and doors to replace. I read in an article that drafts from windows and doors, regardless of age and condition, are caused by air leakage in the home, through the walls and attic, thus "pulling" from the path of least resistance. IMO, since i plan to change the windows, which should improve "exchange", i still need to treat the problem. But this refers more to part 1.
age.... think damage control on a ship... first thing you want to do is get a patch on the hole .... then go after the leaks
a blower door test will show you where to start... go for the air sealing.... then work on the walls
and think about this... your old windows with storm windows are about an r-2
modern windows about r-3
that crummy wall with the bad fiberlass might be r-10
another bad example would be triage.... set your prioritiesMike Hussein Smith Rhode Island : Design / Build / Repair / Restore
agewon
I agree with Mike about trying one room first.
I have insulated existing walls with fiberglass on a number of occasions. We were always disappointed with the amount of insulation we got in the wall.
We used a 1.5" wall insulating tube. http://forums.taunton.com/tp-breaktime/messages?msg=117095.29
Sometimes the tube would snake past the FG and up the wall and other times it would ball up the FG and that make matters worse.
Your biggest problem is finding a good machine and good equipment. For discussion on that read http://forums.taunton.com/tp-breaktime/messages?msg=117095.11
I am not sure what Mike Smith is suggesting. But if you are going to punch 3 -1" or 2" holes in the wall, stick the nozzle in the hole and try to blow thru the FG then you are dreaming. The cellulose is going to catch on the FG and quit flowing.
I am all for trying to get more insulation in a wall, but don't get your hopes up. And search for good equipment. My lumberyard machines are usually pretty pathetic for anything but blowing an attic. Even then it is an hour to get the machine to run and find all the right connections.
If you compress the FG with a good cellulose good job you will improve your R-Value and cut down on air inflitration. It takes an empty wall and a good machine to get a true desnse pack though.
Rich
http://www.retrofoam.com/