Insulation Cellulose vs Fiberglass vs Foam?

[rwalter]

Hello Everyone,

Well here goes, I am curious to see what everyones opinion is on insulations. Especially cellulose, foam and fiberglass (the big 3). All three methods work but all three have their advantages and disadvantages. So here goes the review of my research.

Foam, Open cell and closed Cell

Closed cell  Advantages, -high R value per inch (R6.0-7.0), very little or no air pentetration. Creates it's own vapor barrior. Can be used to create thermal bridges
Disdavantages, Expensive, upwards of $0.80-1.00 per board foot professionally installed (1'x1x1"), specialized equipment needed (not the usual do it yourself job). Shrinkage over time and lead to air penetration's limiting the effect of the insulation.

Open cell-Advantages, -reasonable R value per inch (R3.5.0-4.0), very little or no air pentetration. Can be used to create thermal bridges.
Disdavantages, Expensive, upwards of $0.40-0.60 per board foot professionally installed (1'x1x1"), specialized equipment needed (not the usual do it yourself job). Shrinkage over time and lead to air penetration's limiting the effect of the insulation. Potentially needs a vapor barrior in climates with over 8000 heating degree days.


Cellulose - reasonable R value per inch (R3.5.0-4.0), very little air pentetration (dense pack installation). Reasonably priced, (maybe the lowest priced you do it yourself and it is not professionally installed because its labor intensive to install, Professionally usually a crew of 3-4 guys) and readily avialable, at Big Box retail stores. Can be installed with new construction walls by do it yourselfer with Insulweb or Polyweb netting. ( Retail stores with give you a free rental with a large enough purchase of the insulation.) or Professionally it can be installed by a wet spray techniques. Can create thermal bridges on flat ceilings.
Disadvantages. Not as easy to install as fiberglass. Insulweb is hard to locate (pretty much and online order only for most of us, (do a google search if your interested.) Requires more prep work than fiberglass or foam and there is the potential for settling over time leaving air gaps. Also question on from some inspectors since most are not use to cellulose in new built walls. May require a vapor barrior in some applications especially over 8000 degree heating days or by building code.

Fiberglass, Advantages, Easy to install for the do it yourselfer, Relatively inexpensive, Resonable R-value per inch 3.0-3.5 per inch (low density, High density fiberglass is expensive).

Disadvantages, can allow significant air air penetration  and it is the most of all three forms listed here. Most heat loss is from air penetration in well insulated walls., Requires vapor barrier to be installed. Hard to install around plumbing, electrical, abnormal framing area's (small cavities)

Its late and I am sure I am missing a few items here. Lets see what else everyone can contribute. I am still working on my project //[b]http://countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1119804568[[/b][url] and I just finished my electrical and plumbing inspections. When I get the chance I'll try to post some more photo's. I going to let a professional do the insulation because of time constraints and I gotten 1 quote for fiberglass using R19 in the walls (2x6 walls.) R30 in the cathedral ceiling, R38 in the flat ceilings for a little over $1050, Celloluse blown in is at R21 in the walls, R60 in the flat ceilings and R32 in the cathedral and its estimate was for $2700. I am still waiting on a few more quotes to come back from contractors who visited the site (more foam, fiber and cellulose installers)

Thanks for all the help over the years and I sorry for being absent for so long.

Robert



http://countryplans.com/cgi-bin/yabb2/YaBB.pl?num=1119804568

[glenn kangiser]

Thanks for popping in and posting the info, Robert.  Please keep us posted.

[MountainDon]

That's a good bit of research Robert. That's quite a difference between the fiberglass and cellulose.

If you go with fiberglass, and have the time, you can help with the potential air infiltration problem by sealing all the perforations (electric, plumbing, and so on) with canned foam (like Great Stuff and Dow) before the installer gets there. Seal/caulk around the sill to floor joint. I found a few spots where air was freely passing under the sill plates in my contractor built home.

As time permits please let us know how the rest of it goes.

[rwalter]

Mountain Don

Thanks for the tips. When we built it we did use a sill sealer and caulked the entire sill plate before putting it in place. I agree it would be a good idea going around with a couple of cans of foam and any spots in the walls I can find.

Thanks again for the tip.

Robert

[glenn kangiser]

Seems that one of these could be handy for this if you are doing work on a wall with sheetrock on it already.

You can stand and shoot temps around the room- closer for smaller area readings.



I have the more expensive one for automotive $39 and it is really accurate.


HANDHELD INFRARED THERMOMETER WITH LASER SIGHT


Laser sight lets you draw a bead on the exact location you want to measure.

   * Readings in Fahrenheit or Celsius
   * Temperature range: -27 to 482°F (-33° to 250°C)
   * 40 hour battery life
   * Exclusive ergonomic trigger control
   * 6:1 spot size to distance ratio

Overall dimensions: 4" L x 2" W x 3/4" thick; Includes two CR2032 lithium batteries, lanyard

ITEM 93984-2VGA

$29.99  

Search temperature on Harbor for other models.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=93984

[MountainDon]

Way cool! Or is it Hot? I guess I need one of these to really tell.  

[glenn kangiser]

I checked several known temps with mine a few months back.  It was within about a degree.

I pointed it to the ground in the bright sunlight and found it to be around 132 degrees as I recall.

Possibly there are other uses for it as well. :-?

Maybe a sneak shot around the corner at the little missus could tell you if you had a chance of getting lucky in the near future.

[Sassy]

or whether she's having a "hot flash"  

[wibekkah]

Another advantage of cellulose:  If your stud placement is not perfect (as is the case in our house) you might find that you have to cut the fiberglass to the proper width something that would be a non-issue with cellulose.  Even though this is the case with our place (some studs are more than an inch off-- I don't know why) we have still decided to go with fiberglass.  Not a firm decision but that's what we're planning on using at this point.

[MountainDon]

Sorry to hear about your stud placement being off.  :'(  How did that workout with regards to any sheet goods you may have used? That would be my first concern.

[MountainDon]

This is from one of the Google Ads. DIY foam.

http://www.betterfoam.com/?gclid=COvAlujnv48CFRk0awodzxHDYQ

Everybody click on some of those ad links... make John some money  

[wibekkah]

Sorry to hear about your stud placement being off.  :'(  How did that workout with regards to any sheet goods you may have used? That would be my first concern.

We  had to cut most pieces of plywood but the house is only 28' X 20' so it wasn't too bad.  It's just frustrating that we tried so hard and then  found that we were so far off that we had to cut each blocking piece individually.  It could be worse.  At least using 2X6 means that we don't have to worry about exceeding the limits of the wood and the worst one is about an inch off.  Where it's really going to be a drag is in cutting the insulation to fit.  I may rethink my decision not to use the cellulose.  

[MountainDon]

Re: stud placement being off....

Did you have more than one person marking the stud positions on the plates?

Different folksd makrk and interpret differently sometimes.

[FrankInWI]

I only have 2 X 10s for rafters on my dormers, and 2 X 6 (or 8?) on the trusses.  I want more insulation than that.  I see blowing / expanding foam is $$ but very good BUT he mentions shrinkage and gaps over time.  I don't like that at all!  I'm going to grow old and die in this place, and I'll probably have less income in my 70s, less ability to "fill gaps" when I am 80, yet the price of heating will have skyrocketed some more.

I suppose I could use regular fiberglass rolls of insulation and then put some high density insulation board over that.  Lots of work, and loose ceiling space.  Thoughts appreciated.

[glenn kangiser]

You could fur it out with 2x2s or something then close it to near the top with the wall covering of your choice and then blow in cellulose yourself.  Tinish the top area with a bit of fiberglass where you blew the cellulose in and cover it too -- shouldn't shrink then.  You could screw the top section on to allow checking for settling or get one of the little temperature readers like I posted and check the wall temp to see if there is settling.

[MountainDon]

I have the more expensive one for automotive $39 and it is really accurate.

That sale price is gone for now on the "automotive" model.However, for a little while at least if you select the "order from printed catalog" option and use this part#   91778-7CNH   the price will be $29.99       otherwise it comes up as $59.99

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=91778

.. the part number suffix sets the special pricing

[DemianJ]

Rwalter,

If you choose fiberglass, you're definitely making the right choice to pay someone else to do it.  I was planning on doing it myself and had already had the bales delivered when I read that it is normally cheaper to hire a contractor to do it than to DIY.  Even after paying the restocking fee, I ended up breaking even and didn't have to spend a couple of hot August days putting in itchy fiberglass.

Demian

[rwalter]

Well its crunch time and I am down to choosing between two contractors. So here goes.

Contractor #1, Blown Cellulose behind insulweb netting on the sidewalls and the cathedral (on the flat ceilings I have already installed Dow Super Tuff 1/2" foam board to allow a platform for the insulation to rest on.) The contractor will dense pack all the side walls R(20) and the cathedral ceiling (R31). He is then going to blow in R60 (18") in the flat ceilings. Total price $2800

Contractor #2 Open cell 1/2lb foam. They are going to blow on R13 in the walls and R22 in the ceilings. Price $3200. He states that his insulation will be 10-20% more effecient than the cellulose quote at this level due to zero air penetration.

One curve ball is I have a few contractors that showed up for there appointments and took measurements but haven't gotten back to me with a quote. Prices have ranged from $1080 for Fiberglass (R19 in walls, R30 in cathedral, R38 in Flat ceilings) to a high of ($5400 for Blown cellulose R20,R31, R80 respectively.) I did have a verbal for closed cell 2.0lb foam at a price of around $4800 but I might be off because the secreatary that read me the quote sounded like she was unsure of what she was reading. Hopefully it will show up in the mail but it was supposed to have been mailed 3 days ago.


Well what would you choose. I am leaning toward the cellulose.

Thanks.

Robert

[rwalter]

And the winner is? In my case I have chosen Cellulose.  Due to the cost factor and the total R-value and the amount of air penetration it has it seems like the right choice for me. I had the choice of a 1/2 lb open cell foam for a little more money but I decided to go with the cellulose instead sincel I am worried about the shrinkage in foam opening up air leaks. The open cell foam quotes also had considerably less R-value so it it did shrink some the it wouldn't be as effective as the cellulose.

Well good luck to all and when its done I'll see if I can post some pictures.

Thanks for all the input.

Robert

[FrankInWIS]

Would like to see you're pictures!  

[FrankInWI]

I'm a bit confused.  Are there two types of foam? ...open and closed cell? 

And the alleged shrinkage problem.... I can't seem to find much evidense of that on my googling.... the foams really do shrink?

I'm attrackted to the foam on my 10" rafters cause of greater R value for north wisconsin winters.  I am concerned about the shrinkage reported in this string of discussions, and I have to be concerned for cost. 


Anybody do the do-it-yourself route available from companies on the web?  Still expensive, and if I spray too little, or too much, the saving probably blow up real quick:

http://www.tigerfoam.com/

"Of course, we also welcome your phone call to discuss your particular application and methods if you have any question about using our product. We appreciate your business and look forward to serving your need to seal, insulate, waterproof or fill any area of your structure, home or application that requires great insulation."
http://www.foaminsulation.net/
"Our products are designed to "Stop Air Infiltration" & reduce a home's heating & cooling costs. From sealing around vents, plumbing & electrical penetrations to full wall cavities and rim joists... We have the solutions; the Foam Kit Solutions. For an extensive list of spray foam products, please click on the "Product Page" tab below."

[MountainDon]

I'm a bit confused.  Are there two types of foam? ...open and closed cell? 

The short answer; yep.  But that's nearly all I know other than the closed cell has higher R-value per thickness and will not absorb water as readily as closed cell foam.

I've seen those DIY foam kits. But that's all.

As for shrinking. I've read that it does not shrink, and I've read claims that it may shrink but it was a small factor... something like 2% I think. But IIRC that type is not used much anymore. I think it was on a DOE site where I read that. Anyone else?

[MountainDon]

... and I just dug this up, a PDF saved from somewhere....   

What is the difference between open and closed cell foam insulation?
Open cell foam is usually more suitable for residential applications for several
reasons. Open cell foam is more flexible than closed cell foam. When the framing
members expand and contract with the weather, open cell foam will flex with the wood,
but closed cell foam will get hairline cracks where it was connected to the framing
members because it is not able to flex enough. Another difference between open and
closed cell foam is that, when used at the roof rafters, if a roof leak develops, the closed
cell foam will not allow the water to weep through the foam because it is a vapor
barrier. This can lead to rotting of the roof deck before the roof leak is ever
discovered. Open cell foam is not a vapor barrier, so it allows the water from the roof
leak to weep through the foam to the space below. After the roof leak is repaired, the
open cell foam can be allowed to dry and its thermal properties return, unlike other
insulations that must be replace when they get wet. In addition to these differences
between open and closed cell foam, open cell foam is usually less expensive than closed
cell foam.