In the case you have above the installer wasn't reading his foam. They must be trained to do that as they spray. Temps and conditions are constantly changing thru out the day. Either he wasn't properly trained or if he was,he wasn't doing his job! This is a serious problem with people jumping in to the foam business. A lot of homeowners and builders are looking the best price and end up with someone who doesn't know what they are doing. Hope this info helps. Foam insulation is a great product. It just has to be done right by someone who knows what they are doing.
Open cell spray foam consists of cells that do not completely seal themselves. This makes for a softer and less dense final product. Closed cell foam cells are completely sealed and closed compressed together, creating a denser and firmer final product. This also gives closed cell foam a higher R-value (measured unit of thermal resistance). These differences also affect the cost difference between the two types of insulation.
I used this product to seal and insulate my rim joists as I am finishing the basement. The builder used R13 batt insulation when we built the house 3 years ago. I use a dehumidifier to control moisture in the basement which is below grade. The setting I use is 55%. The dehumidifier kicks on periodically and requires emptying every few days. Since using the foam all around the house on the rim joists and sill plate, the dehumidifier has stayed at 50% for over two weeks since spraying and rarely turns on anymore. I also put the original R13 batt insulation back up after the foam cured.
OK, Peter, I finally went back and read Alex Wilson's article on what he perceives as a serious problem. I haven't seen the full report, but based on the summary he wrote on the Green Building Advisor website, I question the science. It seems to me that he's chosen the wrong metric and he's basing his conclusion on too many assumptions because he doesn't have enough data. You can see my comments at the end of his article.

Where To Purchase Spray Foam Insulation

In general, cantilevered steel beams are a nightmare. If part of the steel beam is in contact with exterior temperatures, then it's best if the interior portion of the steel beam is covered on all sides with insulation. This is generally impossible (because the interior portion of the cantilevered beam generally supports a load, meaning that you can't wrap the steel beam in insulation on all sides).
Note:  A board foot is defined as a 12" x 12" square at 1" thick. Actual output can be affected by a number of factors including temperature and humidity. The theoretical yield has become an industry standard for identifying certain sizes of two component kits. Theoretical yield calculations are performed in perfect laboratory conditions, without taking into account the loss of blowing agent or the variations in application methods and types.

Where To Buy Spray Foam Insulation

I employed a company to insulate my three story house in 2011. They started Insulating it in August of 2011...They said it would be a 3-4 day job. They installed it in 0.5"-8" lifts all in the same cavity, this left burned insulation and voids. They removed what they told me was the bad insulation and in the process cut many electrical wires. They fixed this. They then reinstalled too thick again in some spots and removed again. They then installed it for a 3rd time. The areas that I thought were good are now separating from the structural members leaving voids. As of October 2012, 1 year and 2 months of dealing with the contractor I told them I want proof that what has been installed carries a warranty or I want my money back and I will fix the problems myself. They have yet to provide me with this warranty. I have spent many hours in the house looking at what is bad and they need to fix. I am frustrated, 14 months of additional rent due to their negligence. I would like to know how I can get proof that the product carries the manufacturers lifetime warranty, or has it been installed improperly throughout the entire house. Desperately awaiting your response.  

Today’s “third generation” of blowing agents have a GWP of 700 to 1000 which is still remarkably high considering water/CO2 has a GWP of 1. However, innovation from some chemical manufacturers like the Chemours Company have introduced the next generation of HFO blowing agents such as Opteon 1100, which significantly reduces the GWP impact when using closed-cell spray foam insulation products.
Spray foam comes in two flavors, open cell and closed cell, and provides both parts of the building envelope - the insulation and the air barrier. The building envelope should completely surround the conditioned space, and the insulation needs to be in contact with the air barrier. Since spray foam is both insulation and air barrier, proper alignment of insulation and air barrier is guaranteed.
Good article, but it seems like you can chalk up almost all of those problems to the experience level of whomever is spraying the foam. Spray foam isn't an inherently bad product, but it's pretty easy to botch if the hired company is inexperienced. Fiberglass may be foolproof to install, but then again it has a terrible R-Value compared to a good spray foam. People just need to get referrals and do their homework whenever they research a spray foam contractor.
I am an Architect in Toronto. I am designing a new roof addition to a row house building. Because of existing conditions and the shape of the new roof. It may be easiest to use closed cell spray foam within the areas of the joists. My question is when spray foam is used in this situation do I need to worry about how the joist members may be thermal bridges? It is not common to provide a little bit of rigid insulation to protect the joist members? The additional layer of outboard insulation will require an extra layer of plywood above the insulation which will add to cost.

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