However, coating asphalt shingles and built-up composition roofs requires more caution. The National Roofing Contractors Association’s (NRCA) director of technical services has stated "The roofing industry is aware of a number of issues that could have negative consequences for field application of coatings over asphalt shingle roof systems. Anyone considering this type of application should be aware of the concerns so they can weigh them against the benefits claimed in coating product promotional materials."
Part of that guidance will be explaining that interior, two component foam is applied with the professional using specific personal protective equipment (high-pressure foam is installed while using a respirator, for example). It is encouraged that professionals explain clearly to customers that this equipment, coupled with certain work and engineering practices, including ventilation, is used to minimize exposures to the chemicals used to make SPF during the job.
Sporadic cases of hypersensitivity pneumonitis (HP) have also been reported in workers exposed to isocyanates. The symptoms may seem like the flu, with fever, muscle aches, and headaches. Other symptoms may include a dry cough, chest tightness, and difficult breathing. Individuals with chronic HP often experience progressively more difficult breathing, fatigue, and weight loss. Individuals with acute HP typically develop symptoms 4–6 hours after exposure.
If you're chemically sensitive, it's probably not a good idea to get it installed, but it's also not a good idea to breathe musty air from the crawl space either. In addition, your house and its contents are made of lots of materials that affect your indoor air quality. If you're really concerned about this, hire a company to test your air and tell you what you can do about it.
The guys who sprayed my attic were trained and certified, but I later found out, too late, that they had no experience and my attic was the first they'd ever sprayed. I was also never told to vacate my house for any length of time, and so I (and my pets) were in the house the day they sprayed and the entire time the off ratio foam was filling my home with horrendous vapors. The company kept telling me that it was a good job and I had nothing to worry about, even after I'd had 2 other experienced sprayers from 2 different companies visually examine the foam and confirm that large areas appeared to be off ratio. The 3rd sprayer from yet another company, was also outraged because the company who did my attic had failed to vacuum up all of the old cellulose insulation, and he also noticed areas where the foam was shrinking or pulling away, and this was not even 5 weeks after the spraying.
I have used the Froth-Pak 200 to air-seal rim joists--the area above the foundation wall in a basement. The first time I used it I did not shake the canisters well enough and the foam did not cure properly. Don't just shake the box for a few seconds. I take the tanks out of the box so I can shake/invert each tank for a minute or two. You will be able to hear the chemical sloshing around in the tanks. Also, don't ignore the recommended temperature for application--around 75 degrees F.
once the foam is installed correctly, it is a inert plastic not much different than the foam cushions you sit on. there is not a health rick unless you have off ratio uncured foam that has not mixed properly. the foam is absolutely a health risk in its raw forms before it is mixed and cured. You should not be in the building without proper respirators and eye protection. The spray foam industry should be controlled and regulated by the same standards, testing and inspections that framing ,electrical and plumbing are. until that happens then you will have idiots with spray rigs ruining peoples homes and ruining the market for honest foam contractors that know how to price a job fairly and complete it correctly.
Thank you, Allison. We have a split system unit (actually 5) with the heat being propane. The foam guy said that it needed ventilation, so completely sealing the attic wouldn't be a good idea. It sounds like you are saying that the systems need to be vented out of the attic or replaced with some type of closed system. But I shouldn't bother spraying if the plan is to leave the soffet vents open. Is that correct?
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.