Spray Foam Experinces and Tips. - Page 2

hamsterpower · 12-06-10, 12:14 PM

Quote:

Originally Posted by Higgy

if you wanted to do one room at a time, one year at a time. You could have your whole house spray foamed in less then 10 years.

This is what I'm doing. The coldest room in the house is now the warmest.

Quote:

Originally Posted by Higgy

Just pull down the drywall, get rid of the bat insulation, spray foam, and throw your drywall back up. Tape, seal and paint.

Don't forget: trim, caulk, clean up, and all the little details that "might as well fix now". My project also included, framing, the walls thicker, plumbing (moved a heater for the thicker walls), electrical (moved switches/outlets for thicker walls), and a closet shelf system (to make my wife happy).

Phantom · 12-28-10, 12:03 PM

I have a few questions on doing this in regards to running electric, if the wall is filled with spray foam and a new outlets or switch in needed to be ran (adding a ceiling fan) will the dry wall need to be removed again and have the foam cut out making sure not to hit wires that are there?

How effective would this be if only a 1/4 or 1/2 inch is added then replace the fiberglass and replace the drywall?

hamsterpower · 12-28-10, 12:53 PM

Quote:

Originally Posted by Phantom

I have a few questions on doing this in regards to running electric, if the wall is filled with spray foam and a new outlets or switch in needed to be ran (adding a ceiling fan) will the dry wall need to be removed again and have the foam cut out making sure not to hit wires that are there?

I think you are correct.

Quote:

Originally Posted by Phantom

How effective would this be if only a 1/4 or 1/2 inch is added then replace the fiberglass and replace the drywall?

This is effective as a sealing layer.
In my case I had 3.5 inches of fiberglass that I removed. I then sprayed 2 - 4 inches of foam (to both seal and insulate), added to the thickness of the wall with more framing (to allow more total insulation), and blew in 2-3 inches of cellulose. This layer of cellulose will be easy to add wires through and should insulate better than the original fiberglass.

Next time I use the spray foam I plan to only use a 2 inch layer as the thicker I sprayed the more uneven the results and the harder it was to get a good fill of cellulose.

Ryland · 12-28-10, 08:38 PM

It is best to rewire before adding spray foam, if you fallow current electrical code for outlets (no point on a wally more then 6 feet from an outlet) and run 3 conductor wire to switches (ceiling fan and ceiling light) then there are very few changes or updates that could require rewiring.
But if you want to play it safe, air sealing stud spaces with an inch or less then dense packing with cellulose is also going to be cheaper then solid foam but the foam in the stud space will stop drafts.
The place where it makes sense to use thicker foam is in areas that would otherwise be hard to insulate, like sill boxes and other odd shapes or rough surface.

Sirius · 09-21-12, 07:58 AM

OK, so it looks like Tiger Foam or Handi Foam is the closest thing I'm going to get to calling in a pro with the pressurized paint gun delivery system. I'm OK with that. I'd rather DIY it myself anyway.

Heating the tanks might cost me a few bucks at target to buy some heating pads or an electric blanket to wrap aroung the tanks, but I can work with that. If I short them out... 1 dollar a sq ft as opposed to 7? Seems like a no brainer.

Now my question is... How much does spray foam weigh and can I use it instead of blown in cellulose in my attic? How much of this stuff can I put on top of the dry wall that is my ceiling before it's going to crack the drywall joints or cave in the drywall itself?

Daox · 09-21-12, 11:38 AM

According to Tiger Foam's datasheet, its 1.75 lbs per cubic foot. It is foam, so its pretty darn light.

hamsterpower · 09-21-12, 01:10 PM

Tiger foam is light enough to use in the attic. I would not worry about it caving in. Once cured it is self-supporting. On my kitchen project I covered the ceiling with 3 to 4 inches of foam followed by 8 inches of loose cellulose. (I will add more cellulose after I do other rooms.)

For the heating of the tanks- I heated the first kit with a ceramic heater in a small closet for a day before use. The next two kits, I planned ahead and used them during a heat wave in August, no heating required.

Ryland · 09-21-12, 05:29 PM

The cellulose in my attic weighs around 15 pounds per square foot, we have over 2,000 pounds of insulation in there!
I would only use spray foam to air seal your attic, then use cheap blown cellulose insulation to add the bulk of the insulation value.
As far as weight of foam on the dry wall, the only issue that I see you having is spraying to much foam at one time in a way that it pushes on the dry wall as it's expanding and pops the dry wall loose, but at the same time it will act as a glue and minutes later it will be cured and gluing your whole house together.

S-F · 09-21-12, 05:53 PM

Insulating an attic with spray foam is like building sky scraper and plating it with gold. You could use cellulose instead and have a healthier house and donate a few thousand to feed the hungry. My company recently aquired a spray foam truck and still we only use that stuff for air sealing. NOT insulating. For example: insulating my house to R 40/60 with spray foam would cost about 20 grand. With cellulose it's about 4 thousand. Not to mention ALL of the other drawbacks of using foam.

hamsterpower · 09-22-12, 06:21 AM

Quote:

Originally Posted by S-F

Insulating an attic with spray foam is like building sky scraper and plating it with gold. You could use cellulose instead and have a healthier house and donate a few thousand to feed the hungry. My company recently aquired a spray foam truck and still we only use that stuff for air sealing. NOT insulating. For example: insulating my house to R 40/60 with spray foam would cost about 20 grand. With cellulose it's about 4 thousand. Not to mention ALL of the other drawbacks of using foam.

Thanks for the visual and negativity.

I estimate I can wrap my house in 3 to 4 inches of spray foam for $7000, and get double the r value of what I can fit with cellulose in the space available. I have to air seal anyway. I am working one room at a time and one 600 sf kit does one room perfectly. it just works for me.

09-21-12, 11:38 AM	#16
Daox Administrator Join Date: Aug 2008 Location: Germantown, WI Posts: 5,525 Thanks: 1,162 Thanked 374 Times in 305 Posts	According to Tiger Foam's datasheet, its 1.75 lbs per cubic foot. It is foam, so its pretty darn light. __________________ 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.

12-28-10, 12:03 PM	#12
Phantom Apprentice EcoRenovator Join Date: Sep 2010 Location: Louisville, KY Posts: 101 Thanks: 13 Thanked 8 Times in 7 Posts	I have a few questions on doing this in regards to running electric, if the wall is filled with spray foam and a new outlets or switch in needed to be ran (adding a ceiling fan) will the dry wall need to be removed again and have the foam cut out making sure not to hit wires that are there? How effective would this be if only a 1/4 or 1/2 inch is added then replace the fiberglass and replace the drywall?

12-28-10, 08:38 PM	#14
Ryland Master EcoRenovator Join Date: Mar 2009 Location: Western Wisconsin. Posts: 913 Thanks: 127 Thanked 82 Times in 71 Posts	It is best to rewire before adding spray foam, if you fallow current electrical code for outlets (no point on a wally more then 6 feet from an outlet) and run 3 conductor wire to switches (ceiling fan and ceiling light) then there are very few changes or updates that could require rewiring. But if you want to play it safe, air sealing stud spaces with an inch or less then dense packing with cellulose is also going to be cheaper then solid foam but the foam in the stud space will stop drafts. The place where it makes sense to use thicker foam is in areas that would otherwise be hard to insulate, like sill boxes and other odd shapes or rough surface.

09-21-12, 07:58 AM	#15
Sirius Lurking Renovator Join Date: Sep 2012 Location: Southern Califormia Posts: 20 Thanks: 0 Thanked 2 Times in 2 Posts	OK, so it looks like Tiger Foam or Handi Foam is the closest thing I'm going to get to calling in a pro with the pressurized paint gun delivery system. I'm OK with that. I'd rather DIY it myself anyway. Heating the tanks might cost me a few bucks at target to buy some heating pads or an electric blanket to wrap aroung the tanks, but I can work with that. If I short them out... 1 dollar a sq ft as opposed to 7? Seems like a no brainer. Now my question is... How much does spray foam weigh and can I use it instead of blown in cellulose in my attic? How much of this stuff can I put on top of the dry wall that is my ceiling before it's going to crack the drywall joints or cave in the drywall itself?

09-21-12, 01:10 PM	#17
hamsterpower Apprentice EcoRenovator Join Date: Oct 2009 Posts: 142 Thanks: 0 Thanked 11 Times in 11 Posts	Tiger foam is light enough to use in the attic. I would not worry about it caving in. Once cured it is self-supporting. On my kitchen project I covered the ceiling with 3 to 4 inches of foam followed by 8 inches of loose cellulose. (I will add more cellulose after I do other rooms.) For the heating of the tanks- I heated the first kit with a ceramic heater in a small closet for a day before use. The next two kits, I planned ahead and used them during a heat wave in August, no heating required.

09-21-12, 05:29 PM	#18
Ryland Master EcoRenovator Join Date: Mar 2009 Location: Western Wisconsin. Posts: 913 Thanks: 127 Thanked 82 Times in 71 Posts	The cellulose in my attic weighs around 15 pounds per square foot, we have over 2,000 pounds of insulation in there! I would only use spray foam to air seal your attic, then use cheap blown cellulose insulation to add the bulk of the insulation value. As far as weight of foam on the dry wall, the only issue that I see you having is spraying to much foam at one time in a way that it pushes on the dry wall as it's expanding and pops the dry wall loose, but at the same time it will act as a glue and minutes later it will be cured and gluing your whole house together.