What more is that we also think it is one of the most durable among liquid roof coatings on the market. It can last for several years, working continuously in protecting your roof from outside elements, such as dust, leaves, twigs and debris that would otherwise damage your roof. When it happens, your roof might have leaks and cause discomfort inside your RV. http://www.youtube.com/v/ggLAUsiuI_o?version=3
a) Make sure that your house has been well heated prior to installation because the foam expands at different rates as it hits surfaces with different temperatures. If it is cold outside the sheathing may be much colder than the studs consequently the foam may expand more from the sides of the wall cavity creating air pockets in the wall cavity. This can be minimized by an experienced installer.
If you cut the nails holding one of the corner studs to the bottom plate and the top plate with a Sawzall, you can use a flat bar (or a flat bar plus a wrecking bar) to pull the stud off the sheathing nails. Either re-use the stud, or buy a new stud, and install the stud with toenails as shown in the link I provided in Comment #51 (this link: Outside corner detail).
Steve: If your spray foam installer leaves the vents open, he will be committing the 2nd of the 4 problems I described above. You will most likely have comfort and efficiency problems. You may well have condensation problems. You will be spending a lot of money on a product that likely won't perform as it should. Don't let him leave the vents open. If the installer you've chosen doesn't understand this, you may want to choose someone else.
Closed-cell spray insulation, a rigid medium-density material, can be used in exterior applications such as continuous insulation applications, as well as interior applications. This type of foam insulation has a higher R-value per inch making it also suitable for small areas that require the highest possible R-value to meet building code requirements. Closed-cell spray foam’s rigidity help reject bulk water making it a recognized flood-resistant material by FEMA.