Spray foam safety comes down to installation. Proper installation should result in good product that does not off-gas, poor installations can have very toxic outcomes.
Closed cell foam has some excellent characteristics and can provide important air sealing and insulation properties. I have used spray foam in my house for certain areas where it provides lots of bang for the buck. Educated oversight seems to be required though, since I have also read about some off-gassing horror stories, although thankfully, I have not experienced any myself.
Instructions for proper installation of spray foam - CLICK HERE.
Spray Foam FAQ
Causes of spray foam problems:
Chemicals or product is poor quality
Poor design or planning incomplete
Incomplete or inadequate processing of chemicals
Poor Installation procedures (before, during, and after)
Look for quality manufacturers
Implement best practices for applications and designs
Fault-protection quality assurance for processing equipment
Use only qualified installers /contractors
Require a proven product
Verify the compatibility between products and substrates
Assure that designs and plans consider building science principles for the application
Understand all applicable standards and ensure they are incorporated
No ASTM standards to follow
Qualified architects/engineers must require and specify project standards
Understand Manufacturer’s recommendations and ensure compliance by all involved
General Contractor and Owner Responsibilities
Select a qualified installer.
Select the right product for the application.
Prepare, and protect the substrate before work begins – Ensure proper site protection
Maintain proper conditions during installation
Maintain proper conditions during cure period
Protect the work after the installation and during curing
Prepare the site properly and provide engineering controls before beginning the installation.
Comply with manufacturer’s instructions. Clarify and confirm requirements and tolerances.
Process the materials in accordance with manufacturer’s instructions – verify & document
Install the materials in accordance with manufacturer’s instructions
Understand and comply with post-installation project requirements and protocols
More information on spray foam...
(click on title below to access article)
How Can Something So Toxic Be So 'Green'?
'Green' Spray Foam Can Be Filling Your Home with Toxic Chemicals?
Fine Homebuilding Magazine - "Makers of Spray Foam Named in Law Suits"
U.S. Environmental Protection Agency Info