Spray Foam Experinces and Tips.
 

I've been working on sealing up my house for the last two years, about 6 months ago we had an energy audit with a blower door test done and because of that we really realized how much further we had to go.
The sealing that I started out doing was just the basic feeling for cold spots and drafts, filling in gaps that I could see between my foundation and the last row of siding.
Our energy audit showed that our crawl spaces (sand stone foundation) were the worst, on a 30F degree day there were spots in our crawl space that were 37F degrees, there was some fiber glass "insulation" in there but it was acting more as an air filter, rodent nest and was increasing the area for moisture to condense (it was soggy!) so we got 3 bids and went with the one that was in the middle for price but offered 2" of spray foam, the others were 1" and 1.5", we also opted for a vapor barrier on the dirt floor with a humidistat controlled vent fan that pulls air from under the plastic via perforated drain tile (black plastic drainage pipe), this type of vent fan also works for removing radon, radon is not an issue for us but moisture build up around foundations is not good for any foundation.
So because we have rough stone walls ridged foam would not work so the spray foam was really the best option, it was supposed to be 2 part days to get our project done, one for installing the drain tile and plastic the 2nd to do the foam, after having the spray foam installed we were inspecting the work and realized that the enclosed sill boxes where the joist space runs parallel to the foundation had not been done, at all, then I took a thin sharpened wire and checked the thickness of the foam in the areas that they had done and it was only 2" thick in a few spots! as thin as 1/4" thick in others with a 6 foot stretch where they completely forgot to spray any foam... oops! had to convince the contractor to come back to look at it for him self before he even believed us that anything was less then prefect, after checking on their work even more we found that the top of the foundation inside the sill boxes was also an area that had been missed in 80% of the spaces.
Thing is, when you do a quick check it all looked ok, but start climbing around and you find huge holes and gaps.
5 trips back and 3 months later it's finished, the final touch up I choose to do my self with their can of foam instead of trying to explain where I found all the pin hole drafts.
Now I figured this was simply a single contractor that was doing shoddy work, then my boss had spray foam done at his house, his was even worse! done by a different contractor! this time there were holes that I could reach my arm through, see light through and loose a puppy in, again with foam being as thin as 1/4" thick in areas, at his house they came back a 2nd time that same day, but by that time I had to leave work and that 2nd time they were their they still left holes that you could see light out of and feel drafts, it was amazing!

If I were to do this again I would be very very clear with the contractor that they are responsible for quality control and I would still check up on them, it seems like they miss corners that you can't see well, grope around those corners for drafts and bare spots it is seldom the same person that does the bid as who does the work so talk to the person who is doing the work and make sure that they are clear as to what you expect from them and of course do not pay them until everything has been done and checked and check everything.

There are some contractors that do their own blower door test so they can fallow up and seal the areas that they miss, but those contractors are rare and expensive.

Dang, that sounds like a huge hassle. I'll have to remember that. I was thinking of spray foaming my upstairs when it comes time to add insulation. Can I ask what you paid and approximately how many square feet they covered?

It was 100 feet total of sill box and two crawl spaces with a total of around 65 feet of foundation wall to spray, going up a foot to a foot and a half on the stone wall, stone wall they tend to bid higher because it's uneven.
Our bid, for just for the foam and not for the vent fan or vaporer on the dirt of the crawl space was around $950, so it seemed like a really good price because before we got this bid I was looking at the Do It Yourself two part foam kits cost about a $1.15 per board foot, so to give us the 2" thickness we wanted it would be $2.30 per square foot, I figure we ended up with about 400 square feet of area to cover because of the convoluted shapes that they had to go around, so we could have done it for the same price, only they used a setup using 55 gallon drums of the two part foam with a heater for the foam so it sets up correctly and flows consistently, their setup also had compressed air to blow dust and dirt out of the way, add to that the coveralls, goggles, gloves and most of all with their bulk setup there is no waste where if I order it and run out with 3 square feet left to do then what do I do?
I also found out from talking to other people about it that the kits tend to fail as you empty them so you never get 100% out unless you do have a way to keep them warm (they cool as you empty) and altho I enjoy doing alot of things my self, there are some things that I would rather, even if it takes 3 months, be able to call them up and tell them that it is not done right and that they need to come back and fix it or we are not paying.

We did do our attic our selves, air sealing then blown in cellulose, that is not hard to do and we saved a fair amount of money doing the attic, for the air sealing I bought a Great Stuff Pro foam gun, takes 20-24 ounce cans of one part foam, has a pistol grip, a nice long dispenser tip where the valve is so there is nothing to clog and allows you to use 100% of the can or save it for months without worry of it drying up on you, much much better then the single use cans that you normally see, the pro gun also holds up well enough that I would be willing to loan it to friends, so it can be a worth while investment if you plan to do alot of sealing.

Even with the cost and how long it took it seems well worth it, our floors are warmer, our basement is warmer, less of a chance for rodents and bugs to get in and best of all our furnace is not coming on as much.

my parents just had the sill plates on their new house done with spray foam while the insulators used pink fiberglass in the walls, rigid on the foundation walls and blown in cellulose in the attic. It cost them $4/sqft to have the spray foam done but I went through there afterwords and the crew did a good job on the first pass.

My parents got back quotes as high as $7/sqft to have the plates sprayed.

When is spray foam going to available for DIY at Lowes or Home Depot?

Not sure about those stores, but you can buy the kits online (Tiger Foam is one brand, Handi-Foam is another), price is a little over $1 per board foot, but they do not work well, I used one of the two part foam kits about 6 years back, exact same setup as you can get now, two small tanks with a mixing tip, it worked ok for a while but I would not buy one at the price they are at and I haven't talked to anyone who has tried to use the whole thing who liked it or who would buy them again, they are just to finicky.
The $20,000 setup in a trailer with heated metered pumps seems like a better option, but to get that kind of setup you need to hire the crew to come and use it.

I just used the Tigerfoam kit in my second bedroom. I had everything set up so I could use all the foam in one shot. I was very pleased. I placed the tanks in the bathroom (smallest nearby space) with a small electric heater for about 4 hours at 80 degrees F to preheat them. During application the tanks were in the bedroom with the heater still blowing on them. It took less than 20 minutes to cover the walls in three layers totaling 3-4 inches. While I was spraying I had my dad helping to keep from getting tangled in the hose and shaking the tanks several times. Clean up was easy, much better than after applying Greatstuff foam. I plan to use this kit again when I remodel my kitchen. Next time should go even better as I now know what to expect and know the proper technique.

So the tanks need to stay heated in order for you to apply the spray foam properly?

It would be nice to be able to do this yourself considering how expensive it is. I mean...especially 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. Just pull down the drywall, get rid of the bat insulation, spray foam, and throw your drywall back up. Tape, seal and paint.

I'd like to spray foam my entire basement...but I know that's going to cost a pretty penny to do seeing as I have 1446 sq feet down there. But I know it should be well worth it if the job is done correctly.

Yep, they are supposed to be "warm to the touch" and you have to keep heating them because the pressure drop in the tank cools it, it sounds like hamsterpower had an ideal situation where he had the space and the help to keep everything working smoothly.
If I was air sealing another attic I might get a foam kit instead of the cans and the gun but I would not want to try to work those tanks and heater and everything in a crawl space.

The hose was plenty long to maneuver, but also long enough to get tangled. Now that I know the tanks need to be between 75-85 degrees F, next time I will pick a hot summer day, not a cool fall day. The real trick, at least with the kit I had, was if you stop spraying for 30 seconds you have to change the nozzle or it clogs. I only stopped long enough to wipe the tip clean.

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

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).

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?

I think you are correct.

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.

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.

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?

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

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.

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.

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.

You can also do as AC hacker has done and use rigid foam, and just use expanding foam in a can (great stuff) around the rigid foam. You cut the foam to fit between the joists and use the expanding foam around the edges to seal it up. WAY cheaper and air seals just as well, and you get the same R value per inch if you use rigid polyiso. He has a thread somewhere about it, I think its about his kitchen remodel?

I don't think it is much cheaper, let alone WAY cheaper. Rigid foam is nearly $20 for 2x8' by 2" boards around here and there is too much waste. Then add in several small cans of foam to seal the edges... In AC's thread he said he would use my technique next time.

I didn't realize asking about spray foaming an attic would cause such division. This difference of opinion could actually be very good in coming up with a way to quickly, cheaply, AND qualitatively use spray foam.

I know how it goes, QUICK, FAST, CHEAP pick two.

We might be on to something here. Since I live in southern California, I don't really need to worry about vapor barriers as much as you folks in the frozen north.

I do have a garage that is attached to the house. I even have a contractor acquaintence who is telling me that spray foaming that bit is going to be way expensive and I should forget about it.

I like the spray foam idea in the garage portion that is attached to the living areas. It keeps out the carbon monoxide from the vehicles. I can do the same with plastic and cheaper too, however... I'm in my 40's, by myself, and have a full time job. I'm not going to leave the contents of the garage outside while I take a few days to staple plastic wrap on the ceiling and two walls of the garage. Then go tape up the staples. In this instance, spray foam would be an incredible time saver. And with the eco foam that is out there, I'm not killing the environment.

Back to my attic. Let me remind you, 40's, by myself and full time job. Would spray foam be any faster than cellulose?

And before I forget, has anyone had any experience with the foil shields you put in the attic to reflect heat?

Let me know.

Interesting. Last time I checked it out I thought I priced the rigid foam at quite a bit cheaper. I'll have to double check that I guess.

I can buy foam board up to 3" thick for $0.50 per board foot at R5 per inch of thickness, 2" thick 4'x8' is $30.50

For Cellulose a $10 bag covers 60 square feet at R19 and is R3 to 3.8 per inch, so it's cheap if you have the space and if I remember right the blower to blow it in my attic was $75 for the day, under $1,000 to make my attic R60.

Sorry to come across as negative. Recall that I did say "in an attic". In an attic you have room to spare. That's the sole reason why r60 is recommended in attics as opposed to r40 for walls. Bringing an attic to r60 with spray foam costs a LOT more than it does with cellulose. If you really want you can squirt a "flash" of foam on the entire ceiling and then blow cellulose. Or you can just air seal and use cellulose.

My 600 square foot workshop (built by a previous owner) had numerous small air leaks in the ceiling that I was not able to find and seal. So I pulled out the fiberglass, had about 4 inches foam blown in, then blew in 2 feet of fiberglass on top.

Result is the air leaks are absolutely, positively sealed and I have an R80 ceiling.

The foam cost about $1500. I got a deal from a guy that cut the price to get the order. He was starting a foam business.

Wow R 40 is recommended for walls? Is that in particular regions or everywhere? I was looking at using Tiger Foam, and an inch of that with normal R 13 fiber glass, plus what little R value Drywall and the brick outside walls have only get me to about R 20. Normal wall construction down here in Alabama is 2x4, it just about takes a fist fight to get anything thicker. Not sure how i could even get to R 40.

R 40 is the BSC general recommendation. The code here is only R 20 for walls and R 38 for attics (unless you have electric heat). If you do the energy modeling you will see positive results with added insulation up until around R 40. Above that and the windows dominate the load by such an astounding margin that it makes little financial sense to go further.

Here is a handy guide to air sealing an attic. It is very thorough.

http://www.buildingscience.com/docum...-sealing-guide

If you follow that guide one shouldn't need to put in a thin layer of foam insulation over the whole attic but just where one needs to. One could do the job oneself and seal it equally well while saving big bucks over paying someone else.

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(Apparently "Bang" is too short to post so I'm inserting this here).